The invention relates to an arrangement in a slitter-winder of a fiber web machine according to the preamble of claim 1 . The invention also relates to a method in a slitter-winder of a fiber web machine according to the preamble of claim 8.

In this description and in the claims by thick fiber webs are meant pulp webs and board webs thickness of which is at least 0,25 mm, preferably at least 0,5 mm. In this description the invention has mainly bee described in connection with a two drum winder with two carrier rolls but one of the carrier rolls can be replaced by a set of belt rolls.

In manufacturing lines known from the prior art fiber web making takes place as continuous process. A fiber web completing in a machine is wound with a reel-up around a reeling shaft i.e. reel spool into a machine roll (a parent roll). The purpose of reeling is to modify the web manufactured as planar into a more easily processable form. In the reel-up the continuous process of the machine breaks for the first time and shifts into periodic operation. This periodicity is tried to be made with efficiency as good as possible in order to not to waste already done work in earlier process stages.

The machine roll web produced in fiber web making is full-width so it must be slit into partial webs with suitable width and the partial webs are wound to partial web rolls (customer rolls) with suitable length or with suitable diameter for the customers. The slitting and winding take place as known from prior art in an appropriate separate machine i.e. in a slitter-winder.

As known from the prior art, in the slitter-winder the machine roll is unwound, the wide web is slit on the slitting section into several narrower partial webs which are wound up on the winding section around winding shafts or around winding cores located on the shafts, such as spools, into customer rolls. When the customer rolls are completed, the slitter-winder is stopped and the rolls i.e. the so-called set is removed from the machine after which the process is continued with the winding of a new set. These stages are repeated periodically until paper runs out of the machine roll, whereby the machine roll change is performed and the operation starts again as the winding of a new machine roll. When producing customer rolls of thick fiber web grades and especially when producing customer rolls of pulp, a set of customer rolls of desired diameter is rapidly formed. Once the customer rolls are formed new winding cores / a new winding shaft with new winding cores must be placed in the winder for beginning of winding the next set of customer rolls and the end of each partial fiber web must be lead and attached to the winding core. According to typical prior art arrangements for producing customer rolls of thick web the air blows typically used for thinner fiber web grades are not enough to turn the web end around the core thus typically the slitter-winder is stopped and the web end is attached manually to the winding core by adhesive typically a double sided tape and the slitter-winder is started an the winding of new set of customer rolls is begun.

In US patent publication 7458539 is described a winder roll starting apparatus for thick webs in which scraper with special formed surface or with a blade is used for turning the web end towards the core and pressing the web end onto the adhesive. In US patent application 20050098676 is described a method and a device in connection with winding of a paper or board web, in particular a tissue paper web in which a winding shaft is passed inside the core / cores for the duration of winding. An empty core / empty cores is/are placed on the winding rolls and the winding shaft is brought to the ready position in order for it to be moved inside the core/cores and the winding shaft is pushed inside the core / cores.

On problem relating to winding of thick webs is to achieve enough winding force in the beginning of winding. In prior art there has been attempts to solve this by using in the beginning of winding such that the winding rolls are controlled by speed and torque has been created by using the pressing roll. In some cases these means have not been enough as the traction between the core and the web has been not enough and sliding has occurred. In some cases also the thickness of the start in the point where the first wound layer covers the beginning of the web on the core has caused a bounce that also has lead to occurrence of sliding.

An object of the present invention is to provide for an improved arrangement and method to winding of thick fiber webs.

One problem in connection with prior art arrangements for winding thick fiber webs is that it is not possible utilize enough winding force in the beginning of winding which causes for example web breaks and may result as low quality especially in the beginning layers of a wound roll. A further object of the present invention is to provide an arrangement and method in which the disadvantages of prior art are eliminated or at least minimized.

In view of achieving the objects stated above and those that will come out later the arrangement in accordance with the invention in mainly characterized by what is presented in the characterizing part of claim 1 .

The method in accordance with the invention is mainly characterized by what is presented in the characterizing part of claim 8.

According to the present invention in connection of a slitter-winder of a fiber web machine for thick webs at least during a part of time of the winding torque is transmitted to the fiber web rolls and the arrangement in connection with the winder of the slitter winder has at least one driving motor. This way winding force is provided by this shaft in addition to the winding forces provided by the winding rolls. This also provides for an extra winding parameter to the winding process and gives a further possibility to control the roll formation during winding and gives new means for creating torque especially in the beginning of winding.

According to another advantageous feature of the invention a winding shaft is provided with means for providing winding force at least especially for the beginning of the winding. By the term beginning of the winding in this description and in the following claims is meant the time period from the start of winding to the point when diameter of the roll reaches 500 mm, advantageously 300 mm.

According to an advantageous embodiment of the invention in the beginning of winding the winder is controlled by controlling torque by the means provided with the winding shaft and by a pressing device, especially by a pressing roll, and by a winding roll / winding rolls. According to another advantageous embodiment of the invention in the beginning of winding the winder is controlled by controlling torque by the means provided with the winding shaft and by a pressing device or by a winding roll / winding rolls.

Advantageously at least one driving motor is connected to the winding shaft at least during a part of time of winding and the winding shaft is rotated by this driving motor. According to an advantageous feature the driving motor is releasable from the winding shaft when not in use so that the weight of the driving motor does not load the support structure of the winding shaft and the winding cores.

The driving motor is for example a hydraulic, electric or pneumatic motor. The driv- ing motor can also be integrated as a part of the winding shaft.

According to another advantageous feature a pressure roll of winder is provided with a driving motor for transmitting torque to the roll to be wound.

According to an advantageous feature the winding shaft comprises two shaft elements and the elements are connected to each other for transmitting torque. Ad- vantageously the connection is releasable and transmits torque.

The driving motor further advantageously is connected to a control system for controlling its speed. And in arrangements with two driving motors, one driving motor at each end of the winding shaft, the control system control both driving motors advantageously by feedback controlling. In the following the invention will be described in more detail with reference to the figures in the accompanying drawing, the invention being however not supposed to be in any way strictly confined to the details of said illustration.

Figure 1 is a schematic illustration of an advantageous embodiment of the invention. Figure 2 is a schematic illustration of an advantageous embodiment of the invention.

Figures 3 is a schematic illustration of a winding shaft according to one advantageous feature of the invention.

Figure 4 is a schematic illustration of a two-drum winder. Figure 5 is a schematic cross sectional illustration of a winding shaft according to one advantageous feature of the invention.

In the figures same reference signs are used for same or respective components, part assemblies etc. unless otherwise stated. Some reference signs have been omitted from the figures for the sake of clarity. Figures 1 - 2 show a winder 5 which is a two-drum winder with two winding drums 1 1 , 12. The winder 5 shown in the figure 1 is a two-drum winder 5 which comprises two carrier rolls 21 , 22 and at least two longitudinally successive web rolls to be wound are supported by the carrier rolls 1 1 , 12 from below and by a pressing device ( a pressing roll, not shown) from above the web rolls. In two-drum winders one of the carrier rolls can be a set of belt rolls in which an endless loop/loops of belt/belts is/are arranged around two rolls depending on the type of two-drum winder. In a slitting section preceding the winder 5 fiber web W is slit length-wise into parallel partial webs which are wound in the winder 5 to a set of successive partial web rolls 20. The longitudinally successive web rolls 20 are supported by the winding rolls 1 1 , 12. The winder 5 comprises a winding shaft 10 on which the winding cores are placed and around which winding cores the partial web rolls 20 are formed. One end of the winding shaft 10 is supported in a slide 17 that is movable on guides 16 thus allowing the winding shaft 10 to move in accordance with the winding progresses and the diameter of the partial web rolls 20 increases. On the other end of the winding shaft a driving motor 15 is connected. The driving motor 15 rotates the winding shaft 10 and thus transmitting torque at least during part of the time of winding, advantageously in the beginning of winding. This way winding force is provided by this shaft in addition to the winding forces provided by the winding rolls. This also provides for an extra winding parameter to the winding process and gives a further possibility to control the roll formation during winding. The driving motor 15 is advantageously disconnected from the winding shaft 10 when not used so that the weight of the driving motor 15 does not load the supports of the winding cores.

The end of the winding shaft 10 connected to the slide 17 can also be provided with a driving motor 15 for providing transmitting torque from both ends of the winding shaft 10 as shown in figure 3. In one end or in both ends of the winding shaft the driving motor 15 arrangement comprises a transmission means 18 con- nected to the shaft 10 and connected to the driving motor by connecting shaft 14, for example by a cardan. The connection can also be created by belt transmission means. In the example of figure 3 the winding shaft 10 is constructed of two winding shaft elements 10A, 10B that are connected to each other by a releasable connection 13 that transmits the torque. In the example of figure 3 the driving motor 15 directly connected to the winding shaft 10 is movable with the winding shaft as shown by arrow Z1 and in the other end of the winding shaft the transmission means 18 are movable and connected to the winding shaft 10 only in the begin- ning of the winding and the driving motor 15 can be fixedly attached to the foundation or frame of the winder 5. The driving motor 15 can also have a slide for its movements. The driving motors 15 are controlled manually or by control program and their speeds are linked to each other by control program for example by feedback. In the winding with winding shaft 13 the winding cores 20 are placed around the winding shaft 13 and the winding shaft 13 is expanded such that the winding cores are tightly around the shaft 13. The winding shaft 13 may have some inflatable means placed apart on the circumference, for example three nose hoses, or means inside the shaft to expand the circumference, for example pivoting zones, etc.

In figure 4 a two-drum winder is schematically illustrated. The winder has two winding rolls 1 1 , 12 and a pressing roll 19 and the winding shaft 13. As shown by the arrows in the figure torque for winding is transmitted by the winding shaft 13, by the winding rolls 1 1 , 12 and by the pressing roll 19. Advantageously surface of the pressing roll 19 has strong retaining properties that are accomplished for example by coating, by surface roughness or by grooves etc. Depending on the application and/or situation any of these means for transmitting torque are usable all together or in combinations of the winding shaft 13 and one of the other two or winding shaft 13 alone in the beginning of winding. During winding these means are usable all together or in combinations of two or one means at the time depending on the need of winding.

In figure 5 a schematic cross-sectional illustration is shown of a winding shaft 13 which has on its outer circumference an embedding 3Z for fiber web tail. This place 13Z is formed as an inclined embedding on the circumference of the winding shaft 13. By this arrangement the bounce during winding of the first layers is evened. This embedding may be mechanically formed on the circumference or it may be formed by the circumference expanding means before or even during winding.

Above the invention has been described with reference to some preferred exempli- fying embodiments of the same only, and the invention is, however, by no means to be strictly confined to the details of said embodiments and many modifications and variations are possible.

Reference signs used in the drawing 5 winder

10 winding shaft

10A, 10B winding shaft element 1 1 winding roll

12 winding roll

13 releasable connection

13Z embedding for web tail

14 connecting shaft

15 driving motor

16 guides

17 support slide

18 transmission means

19 pressing means

20 fiber web rolls

Z1 , Z2 arrow