EP0744365B1 - Method for changing the roll in a winding machine and winding machine for carrying out this method - Google Patents

Abstract

The reel changing system has the paper web (3) passed around a carrier roller (1) before feeding onto the winding reel (3.1), with the carrier roller rotated in synchronism with the winding reel during the normal winding and during a creep rotation rate, initiated shortly before the required winding reel dia. is reached. A weakness line is provided across the width of the web and coated with an adhesive during the creep rotation rate, with subsequent adhering of the web to the wound reel and separation of the web along the weakness line, before removal of the completed wound reel.

Description

The invention relates to a method for changing roles in a Winding machine. The invention also relates to one for carrying out this process suitable winding machine. In particular, the Preambles of the independent claims pointed out.

(1) EP 0 340 337

(2) DE-C-36 11 895 (= US 4 775 110)

(3) DE-C-40 34 997 C2

(4) US-A-5 092 533

(5) JP-A-57-085749

(6) WO-A-92/05100

The prior art contains the following relevant publications:

(1) EP 0 340 337

(2) DE-C-36 11 895 (= US 4,775,110)

(3) DE-C-40 34 997 C2

(4) US-A-5 092 533

(5) JP-A-57-085749

(6) WO-A-92/05100

Document (1) shows a winding machine with a central support roller and with (two) outer carrier rollers arranged on both sides of the same. The three Carrier rollers form two winding beds for winding a plurality of Rolls of paper that are made from longitudinally cut partial webs. On Role change is carried out as follows:

As soon as the paper rolls have reached their nominal diameter, (at reduced working speed) traces of adhesive on the partial webs applied so that an adhesive bond with the last layer of each Paper roll is made. For the subsequent cutting of the partial webs different separators are provided. A separator is swung into the first changing bed from below. This is done here Cutting the partial web (s) in that the paper roll (s) from the Changing bed is or will be ejected into a drain table. The second The paper roll (s) located in the changing bed is or are first placed in a Ejected discharge table, after which one sunk in this discharge table arranged separator is brought into its working position. The Cutting takes place here e.g. by lowering the drain table.

Disadvantages of this embodiment: There is a risk that when Eject the paper rolls from the changing beds the just glued Web end is detached from the previous paper layer. It is also disadvantageous that cutting the partial webs in one relatively large distance from the glue points. This leaves on the finished rolls behind the glue points relatively long web ends, which in hang down loosely. It is often necessary to loosen them Cut web ends by hand or by hand on the rolls to stick. Or you need an additional device, which the loose Connects web ends with the rolls.

Document (2) shows and describes a method and a winding machine, which unwinds the paper web from a supply roll and into one Backup roller is guided. The backup roller has a perforated roller jacket and is vacuumable. The paper web wraps around the support roller on one part of their scope. It is at a certain point in the scope of the Back-up roller wound onto a winding tube to form a paper roll. Is a The roll is completely wound, so it becomes the first one running transversely to the running direction Glue track applied to the paper web. Seen in the running direction a perforation is applied to this glue track, through which the web is weakened, and again, subsequently, another crosswise Traces of glue applied on the paper web. Then if the Weakening zone has reached the backup roller, the incoming web (e.g. by slowing down the supply roll) jerkily slows down and thereby at the Zone of weakness severed. The first glue track in the running direction serves the resulting web end to the last layer of the finished roll and the second glue track (seen in the direction of travel) serves to the beginning of the path of the now following path to a new winding tube to stick.

In the separation process described, in which the said The beginning of the path, as stated, has a reduced speed or stopped, the backup roller continues to rotate under the start of the web. This is likely the reason for this is that various shortcomings have been shown in practice to have. One of the shortcomings is that during the phase of Completion of a roll no longer runs in a straight line, but on the outer surface the back-up roller oscillates back and forth.

In particular, there is a risk that after severing the web now created the beginning of the following path on the lateral surface the back-up roller dodges sideways, so that it laterally on the new winding tube arrives staggered; thus the emergence of a flawless new role no longer ensured.

It can also happen that the web is not in the weakened zone tears off, but in front of it, e.g. in an area where the web is clear of Supports running.

The subject of the document (3) is one across the entire Web width traversable weakening element during a standstill the machine against the web resting on a support roller in order to to squeeze the web and thereby weaken it. This traverse movement takes a relatively long time. There is also a risk of Damage to the surface of the backup roller. The complete cut is then done by increasing the web tension.

Also in the construction according to document (4) are transverse to the direction of web travel traversable elements for weakening the web and applying Adhesive provided. Therefore, these steps must again the machine is stopped. This takes time and therefore money.

From the publication (5) a winding machine has become known in which the machine is stopped for changing the wrapping, adhesive applied and the webs are separated from one another by means of a cutting device become.

The document (6) shows a method and a device for changing of winding rolls in machines for winding material webs, especially paper or cardboard webs on cores. To mask the Start of the web on a new sleeve and / or end of the web on a full one Winding rolls become double-sided adhesive strips on the web upset. The adhesive strips are first placed against the web movable transfer element (transfer roller) with less adhesion than applied the material web, then the transfer element (Transfer roller) moved against the web and the adhesive strips to it to hand over.

The invention has for its object a method and an apparatus according to the preambles of the independent claims, with what operational safety during the phase of the roll change - despite automatic process as fast as possible - can be increased. In addition, a Straight running and safe guidance of the web or the partial webs to everyone Be achievable at the time. The finished roll (s) should be behind the glue point have the shortest possible free web end.

This object is solved by the features of the independent claims.

The inventor has recognized that the cause of known in Defects (according to documents 2 or 3) is that the backup roller after cutting the web under the essentially at a standstill new web start continues and at the Paper web grinds. Thereby prevail between the lateral surface of the Backup roller and the web after severing undefined conditions, and the web runs sideways. To solve this Problems are according to the invention that in the characterizing part of claim 1 specified method steps or those in the characterizing part of claim 13 specified device features provided.

Accordingly, is not only during normal continuous operation, but also during the role change ensures that everyone is in contact with the train coming rollers run synchronously with the web, so that in particular between the outer surface of the support roller (s) and the web during the Role change no significant relative speed prevails. A another important measure is that the web at the weakening point is then cut after the web with the last layer of the roll (s) has been glued. This means that the new start of the path is at the moment cutting in the area of the changing bed. All these Measures help to ensure that the new start of the track is relative to the new one Winding sleeve can no longer run laterally. There is still a crucial one Advantage in that the perforation of the paper web and that Adhesive application was not carried out using traversing elements not at a standstill, but at (preferably with a relatively low Machine running speed. This means that it runs preferentially automatic roll change process relatively quickly.

The invention can be different in several winding machines Apply type. Among them are winding machines that only one Back-up roller have (see document (2), Fig. 1), as well as winding machines two or three support rollers, which form one or two changing beds in pairs. In the latter case, the weight in the A roll of compressed air is created in the changing bed being constructed. This includes one from below between two Retractable seal assembly required for rollers (claims 16-18). The arrangement and design of such a sealing arrangement is - thanks to the method of severing the paper web according to the invention when changing roles - much easier, because the from publication (1) known (and can be inserted from bottom to top between two support rollers) Separating device is no longer required. So far has the necessary Consideration of this separator often creates difficulties.

Preferred application of the invention are winding machines (with or without longitudinal cutting device), the "off-line", that is isolated from one Papermaking machine operated. In this case it is Machine speed of the winding machine is generally higher than that of the paper making machine. This usually makes it necessary, according to claim 1, the machine speed for the Changing roles (i.e. temporarily) towards a crawling speed to reduce.

The method according to the invention can have the features of claims 2 to 12 are further developed. To further increase the Operational safety during the phase change phase can be done Working speed of the winding machine after reaching the Gradually reduce the creep speed even further (claim 2). Here in many cases it is beneficial if you keep the work speed during the ejection of the rollers to zero or almost zero. If however, it is desired that the entire roll change operations be carried out in run for a particularly short time, then you can - as long as the Weakened and the adhesive is applied - the Keep creep speed substantially constant (claim 3). Also during the ejection of the roll (s) you can use the winding machine if necessary, let it run slowly (claim 4).

The ejection of the roll (s) is preferably first (according to claim 5) then trigger when the adhesive traces have reached the roller (s) so that the intended web end is glued to the roll. It deviates from this however, it is also possible to eject the roll (s) shortly before trigger, so that the sticking of the web end during the ejection process takes place (claim 6). Claims 7 and 8 relate to different configurations of the method according to the invention a winding machine with two support rollers. Claims 9 and 10 however, relate to special configurations of the method for a Winding machine with three support rollers. A modification for a machine with only a single support roller is specified in claim 11.

All the different process variants can still according to claim 12 be further developed with the aim that the rear of the finished roles the free web ends located at the bond points are particularly short or even are not present. In other words, Claim 12 states that the The weakening point must immediately follow the traces of adhesive. It is it is basically irrelevant whether the application of the adhesive before or after or at the same time as the weakening point is incorporated. However, the adhesive dispenser (with regard to the Arrange web direction) behind the weakening device so that a Contamination of the weakening device with adhesive is avoided.

The invention is explained in more detail with reference to the drawing.

Figure 1 shows schematically a slitter with a carrier roll winding machine.

Figure 2 shows the lateral change in working speed during the role change.

Figures 3 to 5 show the timing of the role change in the 1.

Figures 6 to 8 show the process of changing roles in a Winding machine with three support rollers.

FIG. 9 shows an alternative to FIG. 5.

FIG. 10 shows an alternative to FIG. 8.

FIG. 11 is a top view of the winding machine according to FIG. 10.

Figure 1 shows i.a. a carrier roller winding machine with two carrier rollers 1 and 2, which form a changing bed 19. The support roller 1 has a perforated Roll shell, the interior of which can be connected to a vacuum source. A paper web 3 comes e.g. from a unwind station from a supply roll 10, runs among others via guide rollers 13, 14 and is, for example, from below the support roller 1 brought up. The web wraps around this roller on one Part of its circumference and is on a winding tube 9 to a paper roll 3.1 wound up (or to several rolls of paper 3.1, if one Longitudinal cutting device 15 is activated). It is also conceivable that the train not from the unwind station but ("online") directly from a Paper making machine is fed.

A perforating device 4 is shown schematically preferably according to utility model 29508732; its content is hereby a component of the present patent application. An adhesive dispenser 5 is Part of a plurality of glue dispensers across the width of the paper web 3 are arranged in a row. 7 with a conveyor belt is designated after changing the supply roll 10 to insert the new one Serves at the beginning of the path.

It is shown schematically that the supply roll 10, the support rollers 1 and 2 and for example the guide rollers 13 and 14 are each provided with a drive are. Each of these drives is connected to a control line 30 to 34 central drive control unit 20 connected. This ensures that everyone driven rollers constantly at least approximately synchronous, i.e. With a desired path speed, controllable by means of a Setpoint generator 29.

The following is provided to control the roll change: If the new wound paper roll (s) 3.1 has reached its target diameter or have, this is reported via line 35 to the drive control unit 20. This solves reducing the working speed V of, for example 2500 m / min to a creep speed k (see FIG. 2). Run all drives are still in sync with the train. Now line 22 a control unit 21 is activated, which in turn simultaneously or successively via the lines 24, 25, the perforation device 4 and the Glue dispenser 5 activated. A certain time afterwards, e.g. if the applied adhesive 6 has reached the paper roll 3.1 (Fig. 5), a Signal (e.g. via line 23) further slowing down or stopping trigger all drives. Then the paper roll (s) 3.1 are ejected, indicated by arrow 16, whereby the paper web on the Weakening point 8 (Fig. 5) is severed. It goes without saying that one this sequence of role change processes exceptionally, if necessary, even before the normal nominal diameter is reached Paper roll (s) can trigger. With continuously running relatively slowly Winding machines do not have to reduce the working speed.

1 shows the following: It may be desirable in the changing bed 19 to build up a compressed air cushion, thereby the weight of the Counteract paper roll (s) 3.1. This is intended to reduce the burden of Paper web at the support points 11 and 12 can be reduced. To this The purpose of the winding bed 19 is down by means of a sealing arrangement 26 sealed. In the example shown, this is part of a Compressed air box 27, which is connected to a compressed air source 28. For Cleaning purposes or to remove reject paper can Sealing arrangement 26, 27 are removed downwards. That in the changing bed 19 resulting compressed air cushion is also not shown Side shields sealed to the outside.

As already mentioned, it can be seen from FIG. 2 that the entire slitting machine (Fig. 1) during normal operation Working speed of e.g. 2500 m / min. At a time A has Roll 3.1 almost reached its target diameter. From here on out Working speed up to time B to a creep speed k (e.g. 200 m / min) reduced. This creep speed can last for a while remain constant, as shown with a dash-dotted line or it becomes gradually reduced even further. At time B the Weakening device, e.g. Perforating device 4 started. This is e.g. one over the entire web width and one Perforation comb shaft which makes a single revolution, whereby the perforation comb dips into the web and in this one Weakening point 8, e.g. creates a row of perforations (see e.g. Fig. 11).

Simultaneously or shortly afterwards, namely at time C, the Adhesive dispenser 5 activated, for example until time D. Wear this on the paper web 3 on several adhesive traces 6 (see again Fig. 11). At time E, the entire slitter winder can e.g. shut down become; immediately afterwards (time F) the reel (s) are ejected 3.1, whereby the web is cut along the weakening point 8. If the creep speed k remains constant from time B onwards, this is done stopping earlier, namely at time E '. This also happens Roll ejection earlier, namely at time F '. Another acceleration the entire process can be achieved in that the machine also when ejecting rolls and when inserting new ones Winding sleeves (9, Fig. 5) continues slowly, e.g. at the speed m, which is less than the creep speed k.

The processes just described are repeated in FIGS. 3 to 5 shown. The weakening point 8 has just been created in FIG. 3; the Perforation device 4 is emerging from web 3 again. After that it remains in the rest position (see Figures 4 and 5). In all Figures 3 to 5 is the changing position of the weakening point 8 by marked an arrow. FIG. 3 shows the state at time C. of Figure 2; i.e. the adhesive dispensers 5 have just started Apply traces of adhesive 6 to the paper web 3. Figure 4 shows the State at time D in FIG. 2. Here is the weakening point 8 almost arrived at the glue dispenser 5; that's why now Glue application finished. The distance from the end of the adhesive traces 6 to the weakening point 8 is therefore very small; it can be almost zero become. This makes it possible that the finished, ejected Paper rolls 3.1 also the free end of the web located behind the glue point is extremely short. FIG. 5 shows the state at time E or shortly before this time. The traces of adhesive 6 are partially (or entirely) through Support point 11 (contact line between the paper roll 3.1 and the support roller 1) walked through. As a result, the train is in the area shortly before Weak point 8 with the previous position of the paper roll 3.1 glued. The machine will continue to slow down or at this point stopped; the paper roll (s) 3.1 is / are ejected. The through the cutting of the new beginning of the path is created under the Effect of the negative pressure inside the perforated support roller 1 prevails, held onto the roller shell. Thus, after inserting a start the next winding process with the new winding sleeve 9. Usually has the new winding sleeve 9 an adhesive application to the new beginning of the web to glue her. Alternatively, it is also possible to use the Adhesive dispenser 5 behind the weakening point 8 an additional series of Apply traces of adhesive 6A to the paper web 3.

The embodiment according to FIGS. 6-8 is a Carrier roller winding machine with a central carrier roller 1 and with two outer carrier rollers 2.1 and 2.2 arranged on both sides. So two Changing beds are formed, one of which receives at least one paper roll 3.1 and the other at least one paper roll 3.2, each with a winding tube 9.1, 9.2. In this machine, the paper web 3 is shown by - not shown - Slitter divided into a number of partial webs that are on the central one Accelerate roller 1. These are seen in a top view of the machine Partial webs alternately rolled up in the left and right changing beds (similar to Fig. 11). Each paper roll 3.1, 3.2 is in a known manner Guide heads, not shown, which are inserted into the sleeves 9.1, 9.2 intervention. Each partial web has one or more adhesive dispensers 5 (or 5a, 5b) assigned. The perforating device 4 extends over the entire Machine width. Each paper roll 3.1, 3.2 is one (only symbolic shown) associated ejector 18. The machine works in essentially like the double carrier roll winding machine according to FIGS. 1-5, but with the following differences:

In Figure 6 the machine runs at creep speed k. The is shown Time at which a first weakening point 8 'has just been incorporated has been. The adhesive dispensers 5 just start on the paper roll 3.2 to apply partial web of adhesive 6 '. In Figure 7 is a later one Time shown at which the adhesive application 6 'and the first Weakening point 8 'past roll 3.1. A second The weakening point 8 '' has just been created and that of the other partial web (The roller 3.1) assigned adhesive dispenser 5 produce more Traces of adhesive 6 ''. In Figure 8, the weakening point 8 'has the support point 4.2 of the roller 3.2 on the second outer support roller 2.2 almost reached. The Distance between the weakening points 8 'and 8' 'is chosen so that at the same time the second weakening point 8 ″ the support point 4.1 of the roll 3.1 almost reached on the central support roller 1 '. Here are the web ends already glued to the rolls. The machine has stopped (or is running) further reduced speed m), the ejection of the rollers 3.1 and 3.2 with the help of the ejection devices 18 takes place in different ways as follows: On the first outer support roller 2.1, a brake 17 activated so that the role 3.1 when ejecting the stationary Carrier roller 2.1 rolls. In contrast, the second outer support roller 2.2 remains free rotatable so that when the roller 3.2 is ejected, the latter and the roller 2.2 roll on each other like a rotating pair of gears (symbolic represented by arrows 36 and 37). In both cases Roller ejection in the area of the weakening point 8 '(on the roller 3.2) or 8' ' (on the roller 3.1) generates a high longitudinal tension in the web, so that it is severed properly. That the first weakening point 8 'also in the partial web for role 3.1 is not disturbing.

The embodiment shown in Figures 6 to 8 can be like Modify as follows: You can omit the outer support rollers 2.1 and 2.2 (as indicated by dash-dotted lines in FIG. 6). In this case the paper rolls 3.1 and 3.2 alone by means of not shown Guide bearings, which engage in the sleeves 9.1 and 9.2, in their position the support roller 1 'held. Incorporation of the weakening points 8 'and 8' ' and the application of the adhesive 6 'and 6' 'is in principle the same as described above. Only the distance between the weakening points must be 8 'and 8' 'are provided smaller than in Figures 7 and 8; because that The rollers 3.1 and 3.2 are preferably ejected when the Weakening point 8 '' is just before the support point 4.1 (as in Figure 8) and if at the same time the weakening point 8 '(deviating of Figure 8) shortly before the support point 4.3 of the roller 3.2 on the support roller 1 ' located.

FIG. 9 shows a double carrier roll winding machine in which the Paper web 3 not from below but from above into the winding bed 19 comes in. The first support roller 1 may be without perforation, that is as normal non-absorbent roller. The condition is shown at time E when the machine is at a standstill. The adhesive application 6 and the weakening point 8 are beyond the support point 11 into the Area of the support point 12 arrives, so that now the ejection of the Roll (s) 3.1 takes place on the support roller 2. You can free the support roller 2 circulate; i.e. you can use the same method as for the Roll 3.2 and the support roller 2.2 of Figure 8. Deviating from Fig. 9, this can The reel (s) 3.1 are ejected even when the Weakening point 8 has reached the area of the support point 11.

As already explained with reference to FIG. 1, in turn, the winding bed 19 a compressed air cushion can be built up. The arrangement according to FIG. 9 is Particularly suitable for relatively airtight paper types because of the Compressed air cushion - due to the paper web running from above into the Changing bed 19 - no air can get between the layers of paper. Different in Figure 1: Here it is possible that at the gap 11 air from the Compressed air cushion gets between the layers of the paper web. That turns into with airtight paper grades there is a risk that the outer layers on the side run and / or that a bubble is formed in front of the support point 12. At On the other hand, thin, porous types of paper do not have this danger, for air can escape again.

FIGS. 10 and 11 show a possible modification of that in the figures 6 to 8 shown winding machine. Facilities 38 were added (Seals with compressed air supply) to create compressed air cushions under the winding rollers 3.1 and 3.2. So not only the one running for role 3.2 Partial web, but also the partial web running to role 3.1 from above in their changing bed runs in, the partial webs behind the Attenuation device 4 separated on a guide roller 39. It runs from here Partial web 3a via a further guide roller 40 to the support roller 2.1, the other Sub-web 3b, however, as before directly on the central support roller 1 '. Everyone Some adhesive dispensers 5b and 5a are assigned to partial web 3a, 3b. At Favorable geometric conditions are needed in the partial lanes (instead of two weakening points 8 'and 8' 'one behind the other, 7 and 8) only a single weakening point 8 over the entire To provide web width. This is possible if the in the At least approximated weakening points 8 incorporated into partial webs at the same time get close to the support points 4.1 or 4.2. With others Words: In this case the distance mentioned in claim 9.3 is between two weak points equal to zero. As already explained with reference to FIG. 9, is the arrangement according to Figure 10 - when using the compressed air relief method - universally applicable, i.e. also for processing relatively impermeable paper types.

The weakening device 4 is in all embodiments preferably as a perforating device according to DE-GM 295 08 732.3 educated. The essential parts are a shaft with a Perforation comb 4a, which turns the shaft into the web immersed. Here, the web is by means of an example. gutter-shaped Web support device 4b supported without the perforation comb Web support device touched. This design increases operational safety during the roll change because the perforation line despite continuing Machine inserted into the web at a precisely determinable point and because of the risk of premature tearing of the web Security is avoided.

Claims (19)

1. Method for changing the roll in a winding machine, which at the time of normal operation is operated at a working speed (V) and comprises at least one support roller, with the following features:
   a web to be wound on, for example a paper web (3), is guided to the support roller (1), in which case it loops around the support roller over part of its periphery and is wound on to form a roll (3.1);

   1.2 the travelling web (3) is provided at a certain point, before the web reaches the support roller (1), with a weakening point (8) extending transversely across the web and before this with an adhesive (6) or an adhesive strip, so that this region of the web is stuck to the roll (3.1);

   1.3 both during normal operation, as well as at a reduced speed in comparison with the working speed, the support roller (1) rotates at least approximately in synchronism with the web (3), so that no appreciable relative speed occurs between the web and the surface of the support roller (1);

   1.4 the separation of the web (3) at the weakening point (8) takes place due to the ejection of the finished roll(s) (3.1) from the winding machine,
   the method is characterised in that

   1.5 before the web is provided with the weakening point and with the adhesive, the working speed (V) is reduced to a creeping speed (k) and the weakening of the paper web in the case of a web travelling at the creeping speed, takes place by means of a weakening device extending over the entire web width.
2. Method according to Claim 1, characterised in that after reaching the creeping speed (k), the machine speed (V) is reduced further gradually.
3. Method according to Claim 1, characterised in that after reaching the creeping speed (k), the machine speed (V) is kept essentially constant.
4. Method according to Claim 2 or 3, characterised in that during the ejection of the roll(s) (3.1), the machine speed (V) is set to a value, which lies in the range from zero up to the creeping speed (k).
5. Method according to Claim 1, characterised in that the ejection of the roll(s) (3.1) takes place when the region of the web (3) provided with adhesive (6) has reached the bearing point (11 or 12) of the roll(s) on the respective support roller (1 or 2) and preferably shortly before the weakening point (8), reaches the said bearing point.
6. Method according to Claim 1, characterised in that the ejection of the roll(s) (3.1) takes place shortly before the region of the web (3) provided with adhesive (6) reaches the bearing point of the roll(s) on the respective support roller.
7. Method for separating a paper web when changing a roll in a winding machine with two support rollers (1, 2), which between them form a winding bed for receiving the roll(s) (3.1), according to one of Claims 1 to 6, the web (3) entering the winding bed from below by way of a first support roller (1), characterised in that the ejection of the roll(s) takes place when the region of the web provided with the adhesive (6) has reached the region of the bearing point (11) of the roll (3.1) on the first support roller (1).
8. Method for separating a paper web when changing a roll in a winding machine with two support rollers (1, 2), which together form a winding bed for receiving the roll(s) (3.1), according to one of Claims 1 to 6, the web (3) entering the winding bed by way of the upper region of a first support roller (1), characterised in that the ejection of the roll(s) takes place when the region of the web provided with the adhesive (6) has reached the region of the bearing point (12) of the roll (3.1) on the second support roller (2).
9. Method for separating a paper web when changing a roll in a winding machine with three support rollers, which together form two winding beds for receiving rolls cut to partial web widths, according to one of Claims 1 to 6, characterised by the following features:

   9.1 all partial webs (3) are jointly provided with a first weakening point (8'), which extends transversely over the total web width;

   9.2 at a certain distance thereafter, all the partial webs (3) are provided with a second weakening point (8''), which likewise extends over the total web width;

   9.3 the distance between the two weakening points (8'and 8'') is at least approximately equal to the difference between two web travelling distances L₁ and L₂, L₁ being the travelling distance from the weakening device (4) to the region of one winding bed and L₂ being the travelling distance from the weakening device (4) to the region of the other winding bed.
10. Method according to Claim 9, characterised in that on ejecting the roll(s) (3.1) from the first winding bed, the first outer support roller (2.1) is arrested by means of a braking device (19) and that at the time of ejection of the roll(s) (3.2) from the second winding bed, the second outer support roller (2.2) rotates freely, i.e. driven solely by the ejection movement of the roll(s) (3.2).
11. Method for separating a paper web when changing a roll in a winding machine with a single support roller for supporting rolls cut to partial web widths and staggered with respect to each other, according to Claim 1, characterised by the following features:

    11.1 all partial webs (3) are jointly provided with a first weaking point (8'), which extends transversely over the entire web width;

    11.2 at a certain distance thereafter, all partial webs (3) are provided with a second weakening point (8''), which likewise extends over the entire web width;

    11.3 the distance between the two weakening points (8' and 8'') is at least approximately equal to the difference between the web travelling distance from the weakening device (4) to the bearing point (4.3) of one roll (3.2) on the support roller (1') and the web travelling distance from the weakening device (4) to the bearing point (4.1) of the other roll (3.1) on the support roller (1').
12. Method according to one of Claims 1 to 11, characterised in that the adhesive is applied to the region of the web (3) located directly before the weakening point (8).
13. Winding machine suitable for carrying out the method according to one of Claims 1 to 12, with one, two or three support rollers for supporting the resulting winding roll(s) (3.1), in which case

    13.1 the drives of the support roller(s) and further rollers are controllable by means of a common speed-control device (20);

    13.2 located on the travelling path of the web (3) is a device (4) for producing a weakening point (8) extending transversely over the web as well as a row of adhesive dispensers (5) distributed transversely across the web;

    13.3 a control device (21) is provided, which before changing a roll initiates an actuation of the weakening device (4) and of the adhesive dispenser (5); and

    13.4 the weakening device extends across the entire web width, characterised in that

    13.5 the speed-control device (20) is arranged so that both during normal operation at a working speed (V), as well as at a speed reduced in comparison with the working speed, all the driven rollers rotate continuously at least approximately in synchronism, and

    13.6 upon the announcement of a roll change, a reduction of the working speed to a creeping speed (K) is initiated;

    13.7 the control device (21) is arranged so that it initiates the actuation of the weakening device (4) and of the adhesive dispenser (5) in the case of a web travelling at the creeping speed (K).
14. Winding machine according to Claim 13, characterised in that the control device (21) initiates the actuation of the weakening device (4) and of the adhesive dispenser (5) on reaching the creeping speed (k).
15. Winding machine according to Claim 14, characterised in that upon the expiry of an adjustable time interval after the actuation of the weakening device (4), the control device (21) initiates the adjustment of the working speed (V) to a value which lies in the range from zero to the creeping speed (k).
16. Winding machine according to Claim 14 or 15, with two or three support rollers, which in pairs form a winding bed or two winding beds, characterised in that associated with each winding bed (19) is a device for producing a compressed air cushion, with a sealing arrangement (26) able to be introduced from below into the narrow point between two support rollers (1, 2).
17. Winding machine according to Claim 16, characterised in that a compressed air supply device (27, 28) is associated with the sealing arrangement (26).
18. Winding machine according to Claim 16 or 17, characterised in that the supply of the web takes place from above into the winding bed or into each of the winding beds.
19. Winding machine according to one of Claims 13 to 17, characterised in that the weakening device (4) comprises a shaft with a perforation comb (4a), which at the time of a rotation of the shaft penetrates a channel-like web-support device (4b) and consequently also the web (3).

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