WO2010004522A2 - Apparatus, and method thereof, for processing adjacent webs of flexible material - Google Patents

Abstract

A slitter-rewinder for creating logs (R) of tapes of web material (N) wound around corresponding sets of tubular cores (A), comprises web feeding means for feeding the tapes of web material to a first winder roller (12) which together with a second winder roller (20) defines a winding cradle (21), core insertion means (40) for placing a set of adjacent tubular cores in said winding cradle (21), and web interruption means (70) for severing the web material when a log is completed. The set of tubular cores is introduced in a region (50) upstream, with respect to the web advance direction, a runner (60) made between the first winder roller (12) and the second winder roller (20) and in such region takes place the severing of the web, thanks to the web interruption means (70) that also support the cores in said region (50) keeping them in contact with the first winder roller (12). The slitter-rewinder of the invention allow continuously feeding the web material even during the log change process and it comprises adjusting means that make it suitable to process a wide range of logs and tubular cores sizes.

Description

Description Title of Invention: APPARATUS, AND METHOD THEREOF, FOR

PROCESSING ADJACENT WEBS OF FLEXIBLE MATERIAL

Field of the Invention

[1] The present invention concerns an apparatus for rewinding logs, around a tubular core, of a web material.

[2] In particular, the present invention concerns apparatus, usually called slitter- re winders, comprising means for feeding the web material to a first winder roller which together with a second winder roller defines a winding cradle, means for introducing in said winding cradle a set of tubular cores around which longitudinal adjacent tapes of web material are wound and means for interrupting the web material when a set of logs is completed. Description of the Prior Art

[3] In the paper industry are used apparatus, called slitter-rewinders, that form, from logs of paper based material of big dimensions both in diameter and in length, paper logs for industrial use of small size with respect to the source logs.

[4] Such industrial logs are formed by longitudinally cutting the web material and winding it around a set of adjacent tubular cores having length corresponding to the height of the tapes of web material.

[5] Apparatus of the above type are disclosed for instance in patent documents

US2989262, US3727854 and US4422588.

[6] In US2989262 is described a rewinding machine in which the tubular cores, fed thanks to a feeder with inclined axis, are entered in a winding cradle between two winder rollers by loading means that pick up the tubular cores and put it in the winding cradle by rotating around the axis of the first winder roller so that the cores run an arc of circle above the surface of the first winder roller. Similar unloading means for unloading the completed logs rotate around the axis of the second winder roller.

[7] In US3727854 is described a rewinding machine comprising loading means apt to transfer the cores from a loading station to a winding station and the loading means, just like in US2989262, rotate around the axis of a winder roller, here around the winder roller opposite the one to which is fed the web material.

[8] In US4422588 core loading and unloading means pick up a tubular core, or a set of tubular cores, from a loading station and rotating around an axis placed at a certain distance above a couple of winder rollers, they push away the completed logs and then they put the core in the winding cradle.

[9] Further patent documents disclosing rewinding machines of this type are EPl 108669, EP1623942 and US6129304. [10] All the above documents describe rewinding machine in which the gap between the couple of winder rollers is very small, preventing the cores from passing through it, in fact the cores are loaded in the winding cradle from top. [11] The main relevant drawback of the above machines concerns the need to stop the web material during the log change process, that is when a log is completed and has to be removed from the winding cradle and replaced with a new core.

[12] That undoubtedly leads to a great reduction in the productivity of such machines.

[13] In addiction, the machines disclosed in the above cited documents and in general all the slitter-rewinders of the known art have little versatility, as they are designed to process logs and cores of a specific size and it is difficult to arrange them to process logs or cores of a different size.

Summary of the Invention [14] Object of the present invention is to provide a slitter-re winder able to overcome the drawbacks of the machines of the known art. [15] Further object of the present invention is to propose a slitter-rewinder comprising a couple of winder rollers defining a winding cradle in which are loaded the cores around which the web material winds, also comprising means for loading the tubular cores in the winding cradle and log changing means apt to allow the web material to be continuously fed even during the log change process. [16] Another object of the present invention is to propose a slitter-rewinder able to process, upon simple adjustment and/or little structural modifications, logs and cores thereof of a wide range of sizes and weights. [17] Another object of the present invention is to propose a method for rewinding logs of tapes of web material around a set of tubular cores, said method allowing an improved productivity of the process and also allowing continuously feeding the web material even during the log change process. [18] The above objects are attained through a rewinding machine for the formation of logs of web material slit in a set of adjacent tapes and wound on a correspondent set of tubular cores having length corresponding to the height of the tapes, said rewinding machine comprising:

• web feeding means; D

• core feeding means; D

• a first winder roller; D

• a second winder roller which defines together with said first winder roller a log winding cradle housing said logs during the log formation phase; D

• a third winder roller whose axis moves, referred to said first and second winder rollers, as a function of the diameter of the logs being formed; D • core insertion means for loading the cores in the winding cradle; D

• web interrupting means for interrupting said tapes of web material when a set of logs is completed D and being characterized in that the second winder roller defines with said first winder roller a runner where said set of tubular cores and said adjacent tapes of web material pass through in an early phase of said formation of logs, said core insertion means being placed upstream said runner referred to the web material advance direction.

[19] Advantageously the web interrupting means periodically cooperate with said web feeding means in a region comprised between said core insertion means and said runner.

[20] In addiction, the web interrupting means are also able to keep said tubular core in contact with said web feeding means along at least a portion of said region and, according to a preferred embodiment they swing around a hinge member and are provided with elastic means.

[21] The web interrupting means are also provided with actuator means apt to bring them in contact with said first winder roller in order to interrupt the web material when a set of logs has been wound.

[22] Still advantageously the rewinding machine comprises means apt to synchronize the movements of the web interrupting means and the web feeding means so that the interrupting members of the web interrupting means cooperate with interrupting means integral to the feeding means.

[23] Advantageously the set of tubular cores is supported by a chuck.

[24] Upstream said core insertion means there are core processing means apt to let an end of the interrupted web material adhere to the external surface of said set of tubular cores, thus the formation of a new set of logs begins.

[25] When said core processing means comprise adhesive application means, all the components of the machine placed in a region comprised between an adhesive application station for applying glue and a zone where the web material adheres to the glue applied on said tubular cores provide transversal gaps allowing the passage of the zone of the cores where glue is applied without entering in contact with it.

[26] The core insertion means introduce in said region, at the same time, a set of tubular cores whose axis belong to a same straight line, said core insertion means and said web interrupting means having a plurality of core contact members spaced each other of an amount allowing each tubular core to be contemporaneously supported by at least two core contact members.

[27] The above objects are also attained through a method of formation of logs of web material slit in a set of adjacent tapes and wound on a correspondent set of tubular cores by means of a first winder roller around which at least partially rolls said web material and wherein the first winder roller forms, together with a second winder roller a log winding cradle, said method comprising phases of:

• feeding a set of tubular cores towards a core insertion station; D

• transferring said set of tubular cores in a log winding cradle; D

• feeding said tapes of web material towards said log winding cradle; D

• interrupting said tapes of web material when a set of logs has been wound; D

• removing the formed logs, D wherein said phase of transferring said set of tubular cores in said log winding cradle comprises:

• a first phase of introducing said set of tubular cores in a region upstream, referred to the web advance direction, a runner formed between said first winder roller and said second winder roller; D

• a second phase of passing through said region wherein during said phase the tapes of web material begin winding on said tubular cores; D

• a third phase of said tubular cores and said tapes of web material passing through said runner. D

[28] Advantageously said phase of feeding said tapes of web towards said winding cradle takes place continuously, without stopping in any phase of the method. [29] Still advantageously during said third phase of said set of tubular cores passing through said runner the speed of the second winder roller is set to zero whilst the other winder rollers keep rotating and the web material keep being fed. [30] Alternatively, the speed of said second winder roller is decreased and the other winder rollers keep rotating at a higher speed so that the tubular core is able to pass through the runner. [31] From the above described features are clear the advantages of a slitter-re winder according to the invention and the method thereof for creating logs of web material wound around tubular cores, said advantages mainly concerning the high productivity of the machine that allows high web feeding speed rates and do not need to be stopped during the log change process. [32] Further advantages concern the structural simplicity of the machine and the chance of re-arranging it in a very simple way in order to process tubular cores with a wide range of sizes and to form logs with a wide range of sizes too.

Brief Description of the Drawings [33] These and further advantages of the rewinding machine of the invention will be better understood by way of an embodiment example, that will now be described, with reference to the accompanying drawings, in which:

• figure 1 shows a schematic front view of a slitter-re winder according to the invention; D • figures 2a to 2f show a detail of fig.1 in which are represented the components of a log change assembly in various steps of the log change process taking place when a set of logs is completed and a new one starts winding; D

• figure 3 shows a front view representing the assembly comprising the core insertion means and the chain conveyor feeding the tubular cores to the insertion station, the first winder roller, and the assembly comprising the second winder roller; D

• figure 4 shows a top view of some components of the log change assembly; D

• figure 5 shows a detailed view of fig.1 with the region where the web interrupting means cooperate with the first winder roller; D

• figure 6 shows a view similar to the view of fig. 5 representing a different embodiment of the web interrupting means . D

Detailed Description of Preferred Embodiments

[34] In fig.1 are shown the main components of an automatic rewinding machine for winding around a tubular core a web of tissue paper to form toilet paper logs, kitchen paper logs or the like.

[35] In fig.1 are shown the main components of a slitter-rewinder for winding, around a set of adjacent tubular cores, tapes of web material such as paper, cardboard, non woven material, tissue paper, fabrics or other material.

[36] The web, N, is dragged through a series of traction rollers, 11, until it reaches a first winder roller, 12, where it partially turn around.

[37] Along its path the web passes through a widener roller, 13, which is a tensor roller having curved axis and when the web passes over it is transversally stretched to its maximum height, then it passes through a longitudinal cutting assembly, 17, apt to longitudinally slit the web N in a set of adjacent tapes, and through a punching assembly, 14, composed of a first roller, 15, which has helicoid disposed blades, 16, and of a second roller, 18, mounting a matching surface, 19, and the punching assembly produces in the web transversal perforated lines at the same longitudinal distance and perpendicular to the feeding direction.

[38] A second winder roller, 20, defines together with the first winder roller 12 a winding cradle, 21, where the logs grow. In fact, the first winder roller 12 feeding the web N, the second winder roller 20 and a third roller, 22, rotate at a same peripheral speed so the logs R are put into rotation around their axis. The roller 22 is mounted on a sliding frame, 100, vertically moving on guides, 101, integral to a second sliding frame, 102, and in this way the distance of the roller 22 from the winding cradle 21 can be increased when the logs R grow. A further sliding frame, 103, also vertically moving on the guides 101, supports a centering mechanism, 104, that aligns the axis of the set of logs R. [39] Thanks to further guides, 107, permitting an horizontal translation, the position of the sliding frame 102 is adjusted in order to process tubular cores of a wide range of sizes.

[40] The logs R grow around cores, A, consisting in long tubular elements that are loaded in a feeder, 23, and then they are passed through a core cutting assembly, 88, which splits each core in a set of adjacent tubular cores A. Then the set of cores reach a stop gate, 24, introducing them in special core keeping saddles, 25, transported by a chain conveyor, 26, moving through three tensor members, 27.

[41] The tubular cores, A, housed in the saddles 25 thereof descend along the upper branch of the chain conveyor 26 passing through glue applying means, 30, comprising a glue applying shaped rotating member, 31, and a tank, 32, containing the gluing fluid.

[42] Once passed through said glue applying means 30 the tubular cores A reach the core insertion means, 40, apt to let the cores A enter a region, 50, comprised between the core insertion means 40 themselves and a runner, 60, defined by the gap between the two winder rollers 12 and 20 and designed to allow the passage of the cores that so reach the winding cradle.

[43] In the region 50 the tubular cores A get in contact with the web N dragged by the first winder roller 12 and, thanks to the web interrupting means, 70, the web is severed so that the downstream ends of the tapes of web finishes winding around the logs R and the upstream ends of the tapes of web starts winding around the tubular cores that has just entered the region 50.

[44] The main components of the log change assembly and the log change process are shown in figures 2a to 2f.

[45] In fig.2a a set of logs R in the winding cradle 21 is almost completed. The motorized roller 12 drags the tapes of web N and together with the second winder roller 20 and the roller 22, motorized too, leads the logs R to rotate about their axis thanks to the fact that the three rollers have a same peripheral speed, and this way the web winds around the core.

[46] A set of tubular cores A is placed, ready to be inserted, at the core insertion means 40 comprising a support member, 41, an introducer, 42, pivoting around the support member 41, and a slide, 43, guiding the tubular cores A in the first portion of the region 50 and maintaining them in contact with the first winder roller 12.

[47] In the region 50 operate the web interrupting means 70 that comprise a shaped supporting arm, 71, pivoting around a hinge, 72, and comprising at its end interrupting members, 73, cooperating with the roller 12 to severe the tapes of web. The web interrupting means 70 further comprise elastic means, 74, that keep the interrupting members 73 close to the surface of the roller 12, said elastic means being, in the present embodiment, an air spring comprising an upper shell, 75, rigidly connected to the arm 71 and a lower shell , 76, pivoting around the hinge 72, the two shells defining a chamber, 77, containing a gas under pressure. The lower shell 76 is connected to actuator means, 78, moving it upwards and causing the interrupting members 73 to get in contact with the roller 12, the elastic means 74 acting between the actuator means 78 and the arm 71 in order to limit the pressure of the interrupting members against the roller 12.

[48] In fig.2b the logs R are completed and the introducer 42 rotates picking the cores A from the saddle 25 and taking them in contact with the tapes of web N that are turning around the roller 12.

[49] In fig.12c the tubular cores A, rotated by the friction with the moving web N start rolling on the support member 41 and then on the slide 43 and in this phase the actuator means 78 are operated to take the interrupting members 73 in contact with the roller 12 so that the tapes of web are severed in correspondence to a perforated line previously created by the punching assembly 14.

[50] The upstream ends of the tapes of web tends to fold and lay on the cores A, and there, pressed by the roller against a film of glue previously applied on the cores A, start winding, while the downstream ends of the web complete the logs.

[51] In the following phase, shown in fig. 2d, the tubular cores, going on in the region 50 find the shaped arm 71 that, being elastically adaptable thanks to the elastic means 74, rotates around the hinge 72 pushed by the cores A and at the same time support the cores keeping them in contact with the first winder roller 12. In the meanwhile the centering mechanism 104, having the function of keeping the set of cores adjacent each other and aligned with the tapes of web, disengage the cores; the rotation of the roller 20 is stopped, or decreased, and the roller 22 is slowly moved downwards, so that the completed logs R are unloaded. The centering mechanism 104 move in its bottom end position waiting for a new set of cores.

[52] In fig.2e the tubular cores A keep rolling between the roller 12 and the arm 71, the ends of the tapes of web adhere to the surface of the cores and the logs winding process begins. Then the cores reach the end of the arm 71 where the interrupting members are bound and, passed over the interrupting members they keep rolling on a further slide, 51. In the meanwhile, together with the centering mechanism 104, the roller 22 has moved downwards waiting the new set of logs to be wound.

[53] In fig.2f the tubular cores A, having a first portion of web N wrapped around, have passed through the runner 60 keeping rolling between the winder rollers thanks to the fact that the second winder roller 20 is stopped, or rotates with a peripheral speed lower than the first winder roller 12, and then the cores have reached the winding cradle 21 and a new set of logs is being formed, while, at the same time, a new set of tubular cores is placed in correspondence to the core insertion means 40 ready to be loaded. Obviously the elastic means 74 have taken the interrupting members 73 back in a position close to the roller 12.

[54] It could be easily understood that the slitter-rewinder and the rewinding method thereof above disclosed are very effective and reliable thanks to the improvement of the log change assembly allowing a continuous feeding of the web material even during the log change process that, in this kind of rewinding machines is usually very troublesome.

[55] Obviously, due to the relevant weight of the logs, during the log change process it may be needed to decrease the speed of the web by gradually reducing the speed of the first winder roller 12 and of the other components of the machine involved in the process and by stopping the second winder roller 20 to allow a sufficient speed difference between the two winder rollers so that the completed logs can be unloaded and the cores are able to pass through the runner 60.

[56] Furthermore, it is very simple to process tubular cores of a wide range of sizes. In fact, as shown in fig.3, the core insertion means 40, and the second winder roller 20 are mounted on sliding frames that allow a simple adjustment of their position. In particular, thanks to the guides, 105, the roller 20 can be horizontally translated so that the size of the runner 60 can be fitted to the diameter of the cores, and the assembly composed of the core insertion means 40 and the conveyor chain 26 can be translated, still thanks to guides, 106, in an inclined direction in order to modify the dimension of an early portion of the region 50. The guides 107 too, previously mentioned and allowing the movement of the sliding frame 102, make it very easy to adjust the machine for processing cores and logs of different size. Also mounting the slide 43 with elastic means, 45, is useful to allow processing a wide range of cores.

[57] Certainly many changes could be made and many different arrangements could be provided to optimize the productivity, still remaining in the ambit of the above disclosed invention.

[58] In fig.4 is shown a top view of some components having a structure which is able to effectively support the tubular cores and avoiding at the same time the glue to touch the machine components that come in contact with the cores. In fact, due to the little length of the single cores the distance between two subsequent supporting points in all the components that have to support the cores without being touched by the glue must be reduced. A very effective solution is to provide such components with a rack- like structure where two subsequent core support members are spaced enough to allow the passage of a glue stripe C applied by the glue applying rotating member 31 shaped as shown in figure, but still close enough one to the other so that at least two supporting members come in contact with one core A.

[59] In particular the core keeping saddles 25, the introducer 42, the slide 43, and the shaped supporting arm 71 have the above described rack- like structure, they comprise core contacting members having a very small transversal size and they are transversally positioned in the gaps between two subsequent glue stripes.

[60] Obviously, the problem of letting the ends of the tapes of web adhere to the tubular cores A can be dealt with in a different way, either with solution known in the art or not. For instance, could be used nozzles apt to spray the gluing fluid on the surface of the cores when they are to be inserted in the winding region, as well as cores provided with holes could be used together with means apt to create a vacuum pressure inside said cores so that the web is attracted towards the holes, or even means apt to give the cores an electrostatic charge, or other means could be used.

[61] In fig.5 is shown a detail of fig.l in which there are the interrupting members 73 comprising a series of pads, 79, with a rough surface apt to cerate friction with the surface of the web N. On the surface of the first winder roller 12 there are, transversally arranged in the gaps between the pads 79, further rough surfaces having annular shape and apt to create friction with the other surface of the web, said rough surfaces coming in turns with smooth surfaces facing the rough pads 79. Thanks to the action of the winder roller 12 together with the action of the pads 79 the web is severed. To make it happen along the perforated lines the actuator means 78 must be synchronized with the movement of the web N.

[62] In fig.6 is shown a different embodiment of the interrupting members 73 that may be preferred when the web is not provided with perforated lines.

[63] In this last embodiment the pads 79 are replaced by blades 79' acting together with corresponding counter-blades, 80, bound to the surface of the roller 12 by specific fastening means, 81. Also in this embodiment the web is severed by synchronizing the actuator means 78 with the rotation of the winder roller 12 to let the blades 79' and the counter-blades 80 work together.

[64] Further changes may concern the presence of core guiding components also apt to let them assume the correct transversal position and, at this aim, a chuck could provided inside the tubular core, inserted upstream the log change assembly.

[65] As already mentioned the punching assembly 14 could be eliminated when the tapes of web are severed using the web interrupting means shown in fig.6.

[66] The core cutting assembly 88 as well could be eliminated, for instance in the event the cores are already split when loaded in the feeder 23.

[67] Certainly, many other changes and modifications may be carried out to the rewinding machine of the present invention, mainly with the scope of allowing it processing cores and logs of a wider range of dimensions, by replacing single components with other components having a similar function, still remaining within the ambit of the above disclosed invention and in the ambit of protection defined by the following claims.

Claims

Claims

[Claim 1] Rewinding machine for the formation of logs (R) of web material (N) split in a set of adjacent tapes and wound on a correspondent set of tubular cores (A) having length corresponding to the height of the tapes, said rewinding machine comprising:

- web feeding means;

- core feeding means;

- a first winder roller (12);

- a second winder roller (20) which defines together with said first winder roller (12) a log winding cradle (21) housing said logs during the log formation phase;

- a third winder roller (22) whose axis moves, referred to said first and second winder rollers, as a function of the diameter of the logs being formed;

- core insertion means (40);

- web interrupting means (70) for interrupting said web material (N) when a set of logs (R) is completed, characterized in that said second winder roller (20) defines with said first winder roller (12) a runner (60) where said set of tubular cores (A) and said adjacent tapes of web material (N) pass through in an early phase of said formation of logs (R), said core insertion means (40) being placed upstream said runner (60) referred to the web material advance direction (N).

[Claim 2] Rewinding machine according to claim 1 characterized in that said web interrupting means (70) periodically cooperate with said web feeding means in a region (50) comprised between said core insertion means (40) and said runner (60).

[Claim 3] Rewinding machine according to one of the previous claims characterized in that said web interrupting means (70) keep said tubular core (A) in contact with said web feeding means along at least a portion of said region (50).

[Claim 4] Rewinding machine according to claim 1 o 2 characterized in that said web interrupting means (70) swing around a hinge member (72).

[Claim 5] Rewinding machine according to one of the previous claims characterized in that said web interrupting means (70) are provided with elastic means (74).

[Claim 6] Rewinding machine according to the previous claim characterized in that said web interrupting means (70) are provided with actuator means (78) apt to bring them in contact with said first winder roller (12) in order to interrupt the web material (N) when a set of logs (R) has been wound.

[Claim 7] Rewinding machine according to one of the previous claims characterized in that it comprises, upstream said core insertion means (40), core processing means (30) apt to let an edge of the web material (N) adhere to the external surface of said set of tubular cores (A), thus the formation of a new set of logs (R) begins.

[Claim 8] Rewinding machine according to the previous claim characterized in that said core processing means comprise adhesive application means (30), all the components of the machine placed in a region comprised between an adhesive application station for applying glue (C) and a zone where the web material (N) adheres to the glue applied on said tubular cores, provide transversal spaces allowing the passage of the zone of the cores where glue is applied without entering in contact with it.

[Claim 9] Rewinding machine according to the previous claim characterized in that said core insertion means (40) introduce in said region (50), at the same time, a set of tubular cores (A) whose axis belong to a same straight line, said core insertion means (40) and said web interrupting means (70) having a plurality of core contact members spaced each other in of an amount allowing each tubular core (A) to be contemporaneously supported by at least two core contact members.

[Claim 10] Method of formation of logs (R) of web material (N) split in a set of adjacent tapes and wound on a correspondent set of tubular cores (A) by means of winder roller (12) around which at least partially rolls said web material (N) and wherein the winder roller forms, together with a second winder roller (20) a log winding cradle (21), said method comprising phases of:

- feeding a set of tubular cores towards a core insertion station;

- transferring said set of tubular cores (A) in a log winding cradle (21);

- feeding said tapes of web material (N) towards said log winding cradle; - interrupting said tapes of web material (N) when a set of logs has been wound;

- removing the formed logs (R), characterized in that said phase of transferring said set of tubular cores in said log winding cradle comprises:

- a first phase of introducing said set of tubular cores (A) in a region (50) upstream, referred to the web advance direction, a runner (60) formed between said first winder roller (12) and said second winder roller (20);

- a second phase of passing through said region (50) wherein during said phase the tapes of web material begin winding on said tubular cores; a third phase of said tubular cores (A) and said tapes of web material (N) passing through said runner (60).

[Claim 11] Method according to the previous claim characterized in that during said second phase of passing through said region (50) takes place said phase d) of interrupting said tapes of web material (N).

[Claim 12] Method according to the previous claim characterized in that said second phase of passing through said region (50) takes place thanks to said set of tubular cores (A) rolling on said web interrupting means (70).

[Claim 13] Method according to claim 10 or folio wings characterized in that said phase c) of feeding said tapes of web material (N) towards said log winding cradle (21) takes place continuously, without stopping in any phase of the method.

[Claim 14] Method according to claim 10 or folio wings characterized in that at least during said third phase of said set of tubular cores (A) passing through said runner (60) the speed of said second winder roller (20) is set to zero, whilst the web material (N) keeps advancing.