Method in winding of a paper web and a winding device

Abstract: The invention concerns a method in winding of a paper web, in which method the paper web (W) is unwound from a paper reel (10) and in which method the paper web (W) is slit in a slitter-winder (30) longitudinally into component webs (W n ), which component webs (W n ) are further wound into component rolls. The paper web (W) is passed through the slitting station (40) of the slitter-winder (30), in which slitting station component webs (W n ) are slit out of the web (W) by means of blades (44), and the ends of the slit component webs (W n ) are cut off in a cutter device (45) into predetermined measures before the component webs (W n ) are passed into the winding stations. The winding device in winding of a paper web or equivalent comprises an unwind station (10) and a slitter-winder (30), which includes a slitting station (40), a cutter device (45), and the winding stations for component rolls. The cutter device (45) of the slitter-winder (30) includes an arrangement for cutting the component webs (W n ) into predetermined measures.

Description: The invention concerns a method as defined in the preamble of claim 1. The invention also concerns a winding device as defined in the preamble of claim 5. The invention is related to an arrangement in winding of a paper web, in which a paper web, which has been brought as of full width to the slitter-winder, is slit into narrower component webs, which are further wound into component rolls. The invention is in particular related to a slitter-winder of the bottom draw centre-drive winder type, in which a web of full width, i.e. of the width of the paper machine, is slit into narrower component webs in the longitudinal direction. The invention is, however, also suitable for use in connection with slitter-winders of other types. From the prior art, solutions are known in which, in the tail threading in slitters, devices are used which are based on various blowings and suctions, but it has been noticed that they alone are not sufficiently reliable for passing the leader end of the web to the slitter or for passing the component webs onto the winders for the component webs. At present, in paper mills, out of the various stages of processing, attempts are made to eliminate such stages as require an abundance of manual operations. One problem is the tail threading, which often requires even the work of several persons also at the finishing devices, winders, cutters, etc. Also, in paper machines, high speeds are aimed at, in which case, in a paper finishing device, the web threading must take place as quickly and reliably as possible. With respect to the prior art, reference is made to the FI Patent 91,629 (& EP-A-0 315 569), in which a reel slitter is described, whose function is to slit a web of paper-machine width in the longitudinal direction in a slitting or cutting station. In the arrangement known from this cited paper, a pull-in bar is used, which can be passed through the machine by means of a chain and to which the initial end of the web can be attached. This prior-art reel slitter comprises two support drums, on whose support the webs are wound. The pull-in device provided with a pull-in bar feeds the component webs onto a support drum. Further, a transfer device, which receives the non-adjacent component webs after their separation from the pull-in bars, feeds the webs by means of a suction tube onto a second support drum. In this prior-art solution, a suction tube has been employed as the grasping element for the component webs, which suction tube is a complicated device and has an unreliable adhesion. Further, in this prior-art solution, the cutting off of the ends of the component webs and their possible attaching to the grasping element are difficult to make automatic, so that this solution is primarily suitable for manual operation only. The introduction of the component webs onto the winding drums requires running of the whole slitter-winder back and forth, which is slow and difficult. Further, in this prior-art solution, in the final stage of the passing of the component webs onto the winding drums, the whole slitter-winder is run forwards, in which case the ultimate tightness of the web is determined in accordance with the grasping elements and, thus, remains lower than would be desirable in the beginning of winding. In an arrangement in accordance with one embodiment in said cited paper, problems may be caused by the transfer from the winding drum onto the drum, because the threading bar can tear component webs to be transferred apart from the suction in the drum, in which connection, moreover, the component webs are momentarily indefinitely free (slack) as the threading bar passes through the gap between the drums. Further, the removing of the remainders of web remaining on the threading bar after the cutting must be carried out manually after each threading operation. The object of the invention is to provide a method and a device in winding of a paper web in which drawbacks of the prior-art solutions stated above do not occur. An important object of the invention is to achieve threading of a web of full width into the winding device, which threading operates reliably and during which the work of one person only is required. It is an object of the invention to provide an improved arrangement by whose means the leader end of the web can be threaded and the component webs be separated in connection with a slitter-winder of the bottom draw centre-drive winder type. In view of achieving the objectives stated above and those that will come out later, the method in accordance with the invention is mainly characterized in what is stated in the characterizing part of claim 1. On the other hand, the device in accordance with the invention is characterized in what is stated in the characterizing part of claim 5. In the present invention, the threading of the web and the splitting of the web into component webs in a slitter-winder of the bottom draw centre-drive winder type are achieved quickly and reliably. It is a particularly advantageous feature of the present invention that the web is unwound from the machine reel just once and, moreover, transfer of the component webs onto the winding drums does not require running of the whole slitter-winder. In connection with the arrangement in accordance with the present invention, it is possible, automatically, to drop the remainders of web remaining on the threading bar after the cutting onto the basement floor, from where they can be passed, for example, once in a week into the pulper. In the slitter-winder, the web is passed through the slitter device, in which the web is slit into component webs, to the cutter device, in which the component webs are cut by means of a cutter blade to suitable lengths. Against the guide roll in the cutter device, a nip has been formed by means of a nip roll, which nip is closed before the cutting and through which nip the component webs run. The cutting of the component webs is carried out so that the ends of the component webs extend onto the winding drums to the desired, predetermined points, which are favourable in view of starting the rewinding. The running of the web has been stopped for the time between the cutting to specified measure and the starting of the rewinding. After cutting, the webs passing to the first winding station are separated from the component webs passing to the second winding station, in compliance with preset specifications. The component webs passing to the first winding station are passed, by means of a threading member tightly tensioned between guides, onto the face of the winding drum in the first winding station, to which drum the web adheres by the effect of the suction present in the winding drum, and the threading member is returned to its intermediate position occupied during running. Similarly, the component webs passing onto the winding drum in the second winding station are raised by means of a second threading member onto the face of the winding drum provided with suction, which drum face holds the web end. After this the roll spools are lowered by means of sockets onto the component webs and the winding is started. In the arrangement in accordance with the invention, the start of winding is quick, and a good roll bottom is achieved immediately, because the ends of the component webs are in the correct positions in relation to the reel spools in the directions both of the axis and of the tangent of the winding drum, owing to mechanized cutting, the ends of the component webs are whole and even, the guide roll nip, which has been closed by pressing, keeps the major part of the web length tight, in which case, right at the beginning of the winding, the correct winding tension is obtained, and because the machine reel that is being unwound does not have to be rotated in order to align the ends of the component webs on the winding drums, in which connection the nip of the guide roll can maintain the tension. Out of the reasons mentioned above, the component webs are reliably in correct positions in the cross direction of the machine, i.e. precisely in alignment with the spools. The spools are possibly provided with adhesive, double-sided adhesive tape, or with some other, equivalent arrangement in itself known to a person skilled in the art so as to fix the web end to the roll spool. In the following, the invention will be described in more detail with reference to the figures in the accompanying drawing, wherein Figure 1 is a schematic illustration of a slitter-winder of the bottom draw centre-drive winder type, Figure 2 is a schematic illustration of a slitter-winder, to which a web of full width has been passed, which web is slit into component webs, Figure 3 is a schematic illustration of the slitter-winder in the stage in which the component webs are separated, Figure 4 is a schematic illustration of the slitter-winder in a situation in which a component web is raised into the first winding station, and Figure 5 is a schematic illustration of the slitter-winder in a situation in which a component web is raised into the second winding station. As is shown in Fig. 1, the winder device comprises an unwind station 10, in which there is a paper reel 12, which is unwound as a paper web W of full width. The web W is passed as a bottom draw into the winding device 30, in which the web W is divided into component webs W n and wound into component rolls in a first winding station by means of the winding drum 57 and in a second winding station by means of the winding drum 58. The winding device 30 comprises a slitter part 40, in which the web W is slit into component webs W n ;W 1 ,W 2 ,W 3 , etc. in accordance with predefined settings. Further, the winding device 30 comprises a cutter device 45, by whose means the web W is cut off in the cross direction. As is shown in Fig. 2, in the slitter part 40 of the winding device 30, the blades 44 slit the web W in accordance with predefined settings into component webs W 1 ,W 2 , W 3 . After the slitter part 40, after the component webs W 1 ,W 2 ,W 3 have by-passed the guide roll 33, the nip roll 34 to be placed against the guide roll 33 is controlled into the closed position, in which connection the component webs W 1 ,W 2 ,W 3 run through the nip between the guide roll 33 and the nip roll 34 to the cutter device 45, in which the slit component webs W 1 ,W 2 ,W 3 are cut off in the cross direction to such a measure that the component webs W 1 ,W 2 ,W 3 extend to the desired predefined points on the winding drums 57,58. The component webs passing onto different winding drums must be cut off to different measures unless the geometries of the guide roll 33 and of the winding drums 57 and 58 have been arranged so that the length of the web from the winding stations to the machine reel of the unwind stand is equal, in which case all the component webs can be cut off to the same measure. In the embodiment shown in the figure, the cutting off is carried out so that first all the component webs are cut off to a longer measure of component web by means of the blade 451 against the backup blade 450. After the longer component webs (W 1 and W 3 in Fig. 3) have been raised towards their own winding station, the component webs that remain shorter (W 2 in Fig. 3) can be cut off by means of the blade 452 against the backup blade 450. A second preferred embodiment of cutting off to different measures consists of a cutter blade 451 or 452 that has been arranged to be displaceable. As is shown in Fig. 3, after the cross-direction cutting-off carried out by means of the cutter device 45, the component webs W 1 ,W 2 ,W 3 are separated in different directions by means of separators 46. In the situation shown in the figure, the component webs W 1 ,W 2 ,W 3 passing to different winding stations are separated by means of the separators 46 in compliance with the setting applicable in each particular case. For each component web W 1 ,W 2 ,W 3 , there is a separator 46 of its own, by means of which separators the component webs W 1 ,W 2 or W 3 are transferred into a position from which they are passed to the winding station. The component webs W 1 ,W 3 have been diverted from the plane of the component web W 2 by means of separators. The separators 46 are, for example, articulated bars provided with pneumatic cylinders. In the situation shown in Fig. 4, the threading member 47 has been raised from below through the gap between the separated component webs W 1 ,W 3 and the component web W 2 that remained in its position, in which connection the threading member raises the separated component webs W 1 ,W 3 along with it and carries them onto the winding drum 57. The component webs W 1 ,W 3 passing to the first winding station are carried by means of the threading member 47 onto the face of the winding drum 57, to which face the component web W 1 ,W 2 adheres by the effect of the suction in the winding drum 57. The guide plate 48 prevents falling down of a component web from the threading member 47 and slackening of said component web on the portion between the guide roll 33 and the winding drum 57, which slackening would change the point to which the ends of the component webs W 1 and W 3 finally extend on the winding drum 57. Finally the threading member 47 is returned to an intermediate position for the time of running operation. In the situation shown in Fig. 5, the component webs W 2 passing to the second winding station are passed by means of the threading member 62 onto the winding drum 58. The guide plate 49 permits holding of the component web on its straight track, similarly to the guide plate 48. This drum 58 is preferably also provided with suction. By means of the guide plates 48 and 49, and in particular by means of the guide plate 49, it is possible to regulate the tension of the component webs during their raising onto the winding drums by varying the position of the guide plate in relation to the threading member. The higher the contact pressure is between the end of the component web and the guide plate, the higher is the friction force with which the plate counteracts the gliding of the web and the higher is the tension that is formed in the component web when the threading member 47,62 raises the component web. As comes out from Figs. 4 and 5, the threading members 47 and 62 are bar-like members which extend across the width of the winding device in the cross direction of the component webs W', and said members move along rails 69 provided at both sides of the winding device 30 as tightly tensioned between said rails. The threading member 47,62 is, for example, a wire cable or equivalent guided and tightened from its ends. After this the spools are lowered by means of the sockets onto the component webs, and the winding by means of the slitter-winder is started. The spools can be provided, for example, with adhesive, double-sided adhesive tape, or with any other arrangements in themselves known to a person skilled in the art, by whose means the web is attached to the spools. Above, the invention has been described with reference to some preferred exemplifying embodiments of same only, the invention being not supposed to be in any way strictly confined to the details of said embodiments. Many variations and modifications are possible within the scope of the inventive idea defined in the following patent claims.

Claims: A method in winding of a paper web, in which method the paper web (W) is unwound from a paper reel (10), in which method the paper web (W) is slit in a slitter-winder (30) longitudinally into component webs (W n ), which component webs (W n ) are further wound into component rolls on winding drums (57, 58) of winding stations , and in which method the paper web (W) is passed through the slitting station (40) of the slitter-winder (30), in which slitting station component webs (W n ) are slit out of the web (W) by means of blades (44), characterized in that the ends of the slit component webs (W n ) are cut off in the cross direction by a cutter device (45) so that the ends of the component webs (W n ) extend onto the winding drums (57, 58) to desired, predetermined points. A method as claimed in claim 1, characterized in that , in the method, the component webs (W n ) are separated by means of separators (46) to component webs ( n W) passing to different winding stations, and that the component webs (W n ) passing to the first winding station are transferred onto the winding drum (57) of the first winding station by means of a threading member (47), and the component webs (W n ) passing to the second winding station are transferred onto the winding drum (58) of the second winding station by means of a threading member (62). A method as claimed in claim 1 or 2, characterized in that , after the stilling station (40), the nip roll (34) that is to be placed against the guide roll (33) is controlled into the closed position, after which the slit component webs (W n ) pass through the nip (N) formed between the guide roll (33) and the nip roll (34). A method as claimed in claim 1 or 2, characterized in that , in the method, the component webs (W n ) are made to adhere to the face of the winding drum (57, 58) by means of suction. A winding device in winding of a paper web or equivalent, comprising an unwind station (10) and a slitter-winder (30), which includes a slitting station (40), a cutter device (45), and winding stations comprising winding drums (57, 58) for winding component rolls, characterized in that the cutter device (45) of the slitter-winder (30) includes an arrangement for cutting [the] component webs (W n ) in the cross direction so that the ends of the component webs (W n ) extend onto the winding drums (57,58) to desired, predetermined points. A device as claimed in claim 5, characterized in that the slitter-winder (30) further includes members (46) for separation of the component webs (W n ), which have been slit from the paper web (W) in the longitudinal direction and which have been cut off after threading by means of the cutter device (45) in the cross direction, and threading members (47; 62) for passing the component webs (W n ) onto the respective winding drums (57, 58) of the first and the second winding station. A device as claimed in claim 5 or 6, characterized in that , after the slitting station (40), the device includes a guide roll (33) and a nip roll (34) to be placed against the guide roll, and the slit and cut-off component webs (W n ) pass through the nip (N) formed by said guide roll and nip roll. A device as claimed in claim 5 or 6, characterized in that the winding drums (57,58) are provided with suction so as to make the component webs (W n ) to adhere to the face of the winding drum (57, 58). A device as claimed in claim 5, characterized in that the cutter device (45) in the slitter-winder (30) comprises two blades (451,452) and a backup blade (450) for cutting off the component webs to different lengths. A device as claimed in claim 5, characterized in that the cutter device (45) in the slitter-winder comprises a displaceable cutter blade (451; 452).

Inventors: KOUTONEN PAULI, LESKINEN ARTO, SINKKO JARI, KOUTONEN, PAULI, LESKINEN, ARTO, SINKKO, JARI
Applicants: METSO PAPER INC, METSO PAPER, INC.
Application year: 1997
Main classification: B65H19
IPC codes: B65H35, B65H18, B65H19