(19)
(11) EP 2 045 201 A1

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication:
08.04.2009 Bulletin 2009/15

(21) Application number: 07019379.2

(22) Date of filing: 02.10.2007
(51) International Patent Classification (IPC): 
B65H 19/28(2006.01)
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR
Designated Extension States:
AL BA HR MK RS

(71) Applicant: M T C - Macchine Trasformazione Carta S.r.l.
55016 Porcari (LU) (IT)

(72) Inventor:
  • De Matteis, Alessandro
    55100 Lucca (IT)

(74) Representative: Celestino, Marco 
AB, Agenzia Brevetti & Marchi, Viale Giovanni Pisano, 31
56123 Pisa
56123 Pisa (IT)

   


(54) Rewinding method and rewinding machine that carries out this method


(57) Rewinding machine of a sheet, or web, of paper (1), for making a log (2a) comprising a web feeding roller (3) of the (1) and, downstream, a winding cradle (4) at which the production of the log (2a) is made for winding the web of paper (1) about a core (20). The latter is supplied in a cradle (4) by suitable introduction means, for example a loading unit that draws the cores (20) from a chute guide. Upstream from the feeding roller (3) a perforation roller(11) is provided that acts in combination with a counter-roller (12) to provide a plurality of transversal perforation lines (15) on the web of paper (1) defining a plurality of panels (16). Upstream from the means for introducing the core (20) furthermore, means are provided (50) of application of a measured amount of glue (55) on a determined portion of the web of paper (1), in particular, upstream, portion (17), downstream, portion (18), or bridging the perforation lines (15). The means for applying (50) can provide, for example, a screened roller (51) on which a measured amount of glue is spread by a spreading blade (56) for example equipped with a duct (57) through which the glue is supplied.




Description

Field of the invention



[0001] The present invention relates to a rewinding method in a rewinding machine for making logs of sheet or web material, for example used for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like.

[0002] Furthermore the invention relates to a rewinding machine that carries out this method.

Background of the invention



[0003] Rewinding machines are known where the winding step takes place in a special winding zone comprising an upper roller, a lower roller and a pressing roller.

[0004] For example, in EP 1232980 in the name of the same applicant, a core of cardboard, located on special movable support cradle, is brought into contact with the upper winding roller and is therefore dragged into a winding zone. The rotation of the lower and upper rollers causes the core to rotate at the same speed thus winding around itself the web of paper.

[0005] Normally, before winding, a certain an amount of glue is previously application the surface of the tubular core, to allow the web of paper to remain stuck to core same and to start therefore winding the log.

[0006] To this purpose, glue distribution devices of different kind can be used. For example, nozzles connected to the structure of the rewinding machine can be used that spray a measured amount of glue on the core before that the core enters the movable cradle to start winding. Other devices can be also used such as distributing brush means or knives. Once the log has achieved the predetermined diameter a cutting step follows of the web of paper along special perforation lines.

[0007] To this purpose, as described in EP1554202, a special separation finger is provided brought into rotation at an angular speed higher than the winding roller about which the web of paper adheres, causing therefore the tearing of the paper. Then, a speed difference of rotation between lower roller and pressing roller causes the exit of the formed roll.

[0008] In other cases, a special cutting blade creates a clean cut on the web without any need of auxiliary devices such as the separation finger above described.

[0009] Always as described in EP1232980 a core, previously wet of glue, is brought into contact with the upper winding roller and therefore with the head of the web of paper as obtained from the previous cut or tearing step of the web same, thus starting to wind a log contemporaneously to the exit of the final log.

[0010] Said glue distribution systems have drawbacks on final quality of the product. For example, the glue put on the tubular core of cardboard can cause large droplets of glue to wet the web of paper during the contact of the core with the roller, in such a way that the roller is dirtied and the paper is wound about the upper roller instead of the core. Furthermore, in case of delay of entry of the core with glue in the winding zone, the glue can dry loosing its effect. This would cause a maintenance stop to the machine for removing the core and putting in a new one, with high loss of time and production rate.

[0011] At the end of each winding cycle, the formed log leaves the rewinding machine and is sent to a machine adapted to glue the free end. The methods of gluing this free end are many and in any case need an additional gluing section of the machine. For example, by air specially directioned jets, the free end of the formed log is stretched on a support plane. Then, gluing systems spread glue for all the length of the free end sticking the latter on the final log. However, the free end gluing unit, as well as the gluing step of the starting ed of the log, create relevant problems.

[0012] In fact, the free end cannot be precisely stretched on a support plane, being this responsive to the direction of the air jets. Therefore the final closure is often faulty, with presence of large wrinkles and, in particular, of free end portions folded on themselves.

[0013] In US 7175126 a system is described adapted to avoid the use of the above described external gluing units and to provide the application of the glue in the rewinding machine.

[0014] In a first exemplary embodiment, the glue is applied directly on the core in the cradle by means of two gluing guns. The synchronization of the two gluing guns can lay glue on the core in predetermined instants such that the rotation of the core same transfers the glue by contact on the web of paper upstream and downstream of the desired tearing line. However, this system is not much reliable, since a slip of the core and therefore a subsequent loss of rotational speed of the core causes an incorrect distribution of the glue causing, for example, the free nend not to stick to the roll, or in particular, a faulty start of the new winding cycle.

[0015] The alternative solution provided by the above described patent of spraying the glue on the paper by means of two gluing guns located in the cradle has relevant drawbacks. An inaccurate movement of the core in the cradle, or a not controlled of the web of paper owing to the contact of the core with the web can, in fact, affect the application of the glue on the paper at predetermined points, causing the core to jam in the cradle obliging a maintenance stop.

Summary of the invention



[0016] It is therefore a feature of the present invention to provide a rewinding machine that allows the distribution of the glue near the tearing and/or cutting line of the paper in an effective way for completing a log and starting a new one.

[0017] It is also a feature of the present invention to obtain log having a high quality to minimize the number of discarded logs and the time for maintenance stop.

[0018] It is also a feature of the present invention to provide a rewinding machine that assists remarkably the production process of the log of paper simplifying the structure of the machine with respect to the machines of prior art.

[0019] It is, furthermore, a feature of the present invention to provide a rewinding machine that substantially prevents residual glue from entering between the mechanical moving parts jeopardizing the correct operation and damaging the machine as occurs in the rewinding machines of prior art.

[0020] These and other objects are achieved by a rewinding machine for making logs of sheet or web material, for example used for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising:
  • feeding means a web of paper along a feeding direction;
  • means for perforating and/or cutting the web of paper adapted to make perforation lines and/or clean cut along all the width of said web;
  • a winding cradle downstream of said feeding means where it is carried out the production of the log for winding said web of paper about a core;
  • means for introducing said core into said winding cradle;
  • means for cutting or tearing the web making a formed log tail end and a head end of the new log,
  • means for removing the formed log,
whose main feature is that it comprises, furthermore:
  • means for applying a measured amount of glue on a predetermined portion of said web of paper, said means for applying being arranged upstream from said means for introducing said core into said winding cradle.


[0021] Advantageously, the measured amount of glue can be applied only downstream of the perforation and/or clean cut transversal line, i.e. on the portion of the web of paper corresponding to the formed log tail end to allow closing the log once removed the formed log after cutting or tearing the web of paper.

[0022] Alternatively, or in addition, the measured amount of glue can be applied upstream from the perforation and/or clean cut transversal line, i.e. on the portion of the web of paper corresponding to the head end of the new log that is brought to stick on a corresponding core once removed the formed log, after cutting or tearing the web of paper.

[0023] In a further exemplary embodiment, the portion of said web of paper on which the measured amount of glue is applied can be arranged bridging the perforation and/or clean cut transversal lines. This way, when separating the log consisting of the new log of paper, both the formed log tail end and the head end of the new log comprise glue points. Therefore, it is possible to effect a single application of glue for both closing the formed log tail end and sticking the head end on the core to start winding the new log.

[0024] In particular, means can be provided for measuring the length of the web starting from a large roll of paper operatively connected to the means for applying. More in detail, the means for measuring operate the means for applying the measured amount of glue to achieve a measured length of the web of paper.

[0025] Advantageously, the means for applying are movable towards/away from the web of paper operated by an actuator selected from the group comprised of:
  • a pneumatic actuator;
  • a hydraulic actuator;
  • a electric actuator.


[0026] According to another aspect of the invention, a rewinding machine is provided for making logs of sheet or web material, for example used for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising:
  • feeding means a web of paper along a feeding direction;
  • means for perforating and/or cutting said sheet, or web, of paper adapted to make transversal perforation lines and/or clean cuts on said sheet, or web, of paper;
  • a winding cradle downstream of said feeding means where said log is made by winding said web of paper about a core;
  • means for introducing said core into said winding cradle;
  • means for applying a measured amount of glue on a predetermined portion of said sheet, or web, of paper,
  • means for cutting or tearing the web making a formed log tail end and a head end of the new log,
  • means for removing the formed log,
whose main feature is that said means for applying comprises a single application element adapted to apply said measured amount of glue in at least one of the following portions of said web of paper:
  • upstream from said perforation and/or cut line;
  • downstream of said perforation and/or cut line;
  • bridging said perforation and/or cut line.


[0027] According to a further aspect of the invention, a rewinding method is provided for making logs of sheet or web material, for example used for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising the steps of:
  • feeding said sheet, or web, of paper along a feeding direction;
  • winding said web of paper about a core at a winding cradle;
  • applying a measured amount of glue on said web of paper, said application being carried out upstream from an introducing zone of said core into said winding cradle.
  • cutting or tearing the web making a formed log tail end and a head end of a new log;
  • introducing a core into said winding cradle, starting winding the new log, removing the formed log.


[0028] A winding method, alternative to the previous, for making logs of sheet or web material, for example used for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprises the steps of:
  • feeding said sheet, or web, of paper along a feeding direction;
  • winding said web of paper about a core at a winding cradle;
  • applying a measured amount of glue on said web of paper;
  • cutting or tearing the web making a formed log tail end and a head end of a new log;
  • introducing a core into said winding cradle, starting winding the new log, removing the formed log;
wherein said application is made at said winding cradle owing to a single application element that spreads said measured amount of glue in at least one of the following portions of said web of paper:
  • upstream from said perforation and/or cut line;
  • downstream of said perforation and/or cut line;
  • bridging said perforation and/or cut line.

Brief description of the drawings



[0029] Further characteristic and the advantages of the rewinding machine, according to the invention, will be made clearer with the following description of an exemplary embodiment thereof, exemplifying but not limitative, with reference to the attached drawings, in which like reference characters designate the same or similar parts, throughout the Figs. of which:
  • Figures from 1 to 4 show diagrammatically elevational side views of a first succession of steps through which the rewinding machine, according to the invention, is capable of making logs of sheet or web material, for example used for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like;
  • Figures from 5 to 7 show diagrammatically elevational side views of a succession of steps alternative to that shown in Figs. from 2 to 4 wherein the rewinding machine, according to the invention can work;
  • Figures from 8 to 10 show diagrammatically elevational side views of a succession of steps alternative to that shown in Figs. from 2 to 4 and to that shown in Figs. from 5 to 7 where the rewinding machine can work, according to the invention;
  • Figures from 11 to the 13 show three further exemplary embodiments of the rewinding machine, according to the invention.

Description of a preferred exemplary embodiment



[0030] With reference to Fig. 1, a rewinding machine of a web 1 for making a log 2a comprises a feeding roller 3 of web 1 and, downstream of it, a winding cradle 4 at which the production is made of log 2a for winding the web of paper 1 about a core 20. The latter is supplied into cradle 4 by suitable introduction means, for example a loading unit that draws the cores 20 from a chute guide, not shown in the figure.

[0031] The cradle 4, according to the prior art, comprises a upper winding roller 5, a lower winding roller 6 and a pressing roller 7. The latter follows the growth of the log 2 with the task of assuring its continuous contact with the winding rollers 5 and 6 controlling its diameter growth.

[0032] Upstream from the feeding roller a perforation roller 11 3 is provided that acts in combination with a counter-roller 12 to provide a plurality of transversal perforation lines 15 on the web of paper 1 defining a plurality of panels 16.

[0033] Among the feeding roller 3 and the upper winding roller 5, furthermore, a cutting roller 10 can be provided. The latter can work in combination with the upper winding roller 5 for carrying out a clean cut on the web of paper 1 whenever a number of panels 16 is obtained corresponding to a complete log. By cutting the web of paper 1 two free ends are generated corresponding to the tail end 1a for log 2a formed and at the head end 1b for log 2b.

[0034] If cutting roller 10 is not present, the separation of log 2a and 2b is made at determined perforation lines 15. This is made regulating, as well known, the relative speed of the winding rollers 5, 6 and 7. Even in this case, the separation made at the perforation line 15 generates a tail end 1a for formed log 2a and a head end 1b for new log 2b.

[0035] According to the invention, upstream from the means for introducing the core 20 means are provided 50 for application of a measured amount of glue 55 on a determined portion of the web of paper 1.

[0036] The means for applying 50 can, for example, provide a screened roller 51 on which a measured amount of glue is periodically spread by a spreading blade 56 for example equipped with a duct 57 through which the glue is supplied.

[0037] Upstream from the feeding roller 3 means can be provided for measuring the unwinding steps of the web of paper 1 starting from a large roll not shown in Fig. advantageously. The latter is operatively connected to the means for perforation in order to operate them to provide the perforation lines 15 at predetermined distances, by cutting roller 10, if it is present, to allow separating two consecutive logs, and with the means for applying 50 in order to operate them for applying a determined amount of glue at predetermined perforation lines 15.

[0038] More in detail, the means 50 for application are provided movable from a first position, where the screened roller 51 is distant from the web of paper 1 (Fig. 1) to a second position, where the roller 51 is next to the web of paper 1 for applying a layer of glue 55 at predetermined portions of the web 1 (Fig. 2, 5, 8, 11, 12, 13). For example, the screened roller 51 can be operated in the movement towards/away from the web of paper 1 by a hydraulic, or pneumatic, or electric actuator.

[0039] In a first exemplary embodiment, shown in Figs. from 2 to 4, the layer of glue 55a is mounted by the screened roller 51 only at portion 18 of the web of paper 1 arranged downstream, to determine perforation lines 15'.

[0040] In particular, the perforation line 15' corresponds to the perforation line at which the cutting roller 10 cuts the web of paper 1 separating it into the tail end 1a of the formed log 2a and head end 1b of the new log 2b.

[0041] More in detail, the tail end 1a of the log 2a has the layer of glue 55a for stopping the formed log 2a.

[0042] On cores 20 a layer of glue 53 can be previously applied, for example by a nozzle sprayer 52 arranged between the feeding means of the core 20 and the cradle 4. In this case, the core 2b with the layer of glue 53 is put into cradle 4 and then approached to the web of paper 1 when the portion 17 arranged upstream from the perforation line 15' reaches it.

[0043] The approach of the core 2a to the web of paper 1 can be made, for example by a rotation about axis 19 of the cradle 4 operated by an actuating rod 9.

[0044] In an alternative exemplary embodiment shown in Figs. from 5 to 7, the roller 51 applies the layer of glue 55 in the only portion 17 of the web of paper 1 arranged upstream from the perforation line 15'.

[0045] The portion 17 of the web of paper 1 on which the layer of glue 55b is mounted corresponds, in this case, to the head end 1b that is made by the cut carried out at the perforation line 15' by the cutting roller 10 (Fig. 6).

[0046] In particular, the layer of glue 55b allows at the head end 1b sticking with core 20b put in cradle 4 when this approaches the winding roller 5, as described for the previous case. This way, winding the web of paper 1 about core 20b is started forming a new log 2b.

[0047] In this case, the tail end 1a of each log at the exit of the rewinding machine can be then connected to the relative log by a gluing machine of traditional type arranged downstream of the rewinding machine not shown in the figure.

[0048] According to the invention and diagrammatically shown in Figs. from 8 to 10, roller 51 can be also operated for applying a layer of glue 55 both on the portion 17 and on the portion 18 of the web of paper 1 at the perforation lines 15'.

[0049] In this case, the roller 51 is firstly approached to the web of paper 1 at the portion 18 where a first layer of glue 55a is applied, then arranged according to the withdrawn position 50a (dotted line) at the perforation line 15', and again approached to the web of paper 1 at the portion 17 for applying a second layer of glue 55b. This way, both the tail end 1a of the formed log 2a and the head end 1b of the new log 2b, obtained by cutting the web of paper 1 through cutting roller 10 (Fig. 9), have respective layers of glue 55a and 55b. This allows to glue both to the tail end of formed log 2a and the head end of the new log 2b, avoiding then the use of other gluing systems.

[0050] A same result, with possibility to use also a glue of different type, can be obtained using two different screened rollers 51a and 51b, as diagrammatically shown in Fig. 11. In this case, for applying the glue 55 both on the portion 17 and on the portion 18 of the web of paper 1, it is enough to operate at the same time the screened rollers 51a and 51b working in corresponding positions of the rewinding machine, or operating only one in two consecutive instants.

[0051] A similar result can be also obtained with the further exemplary embodiment shown in Fig. 12. In this case, the roller 51 applies the layer of glue 55 bridging the perforation lines 15. Even in this case it is possible to stop both the tail end 1a on the formed log 2a and starting winding the new log 2b on the core 20b by sticking it with the head end 1b.

[0052] Finally, in Fig. 13 an exemplary embodiment is shown that provides arranging the screened roller 51 at the cradle 4. As shown in figure, the layer of glue 55 can be mounted by roller 51 downstream of the perforation line 15.

[0053] The rewinding machine above described, assists remarkably the production process for the log of paper. In fact, it avoids the need of using expensive and bulky gluing machines usually arranged downstream of and upstream from the machine to provide respectively the application of glue on the cores and on the end portions of the formed log.

[0054] Furthermore, it reduces remarkably with respect to the prior art rewinding machines residues of glue that can enter between the mechanical moving parts jeopardizing the correct operation and causing necessary maintenance stops to avoid damaging the same.

[0055] The foregoing description of a specific embodiment will so fully reveal the invention according to the conceptual point of view, so that others, by applying current knowledge, will be able to modify and/or adapt for various applications such an embodiment without further research and without parting from the invention, and it is therefore to be understood that such adaptations and modifications will have to be considered as equivalent to the specific embodiment. The means and the materials to realise the different functions described herein could have a different nature without, for this reason, departing from the field of the invention. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.


Claims

1. A rewinding machine for making logs of sheet or web material, for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising:

- means for feeding said web of paper along a feeding direction;

- means for perforating and/or cutting said web of paper adapted to make transversal perforation lines and/or clean cuts on said sheet, or web, of paper;

- a winding cradle arranged downstream of said feeding means where said log is made by winding said web of paper about a core;

- means for introducing said core into said winding cradle;

- means for cutting or tearing the web making a formed log tail end and a head end of the new log,

- means for removing the formed log,

characterised in that it comprises, furthermore:

- means for applying a measured amount of glue on a predetermined portion of said web of paper, said means for applying being arranged upstream from said means for introducing said core.


 
2. Rewinding machine, according to claim 1, wherein said measured amount of glue is application said sheet, or web, of paper at least at one of the following web zones:

- upstream from said perforation and/or cut line, whereby it is possible to close said web of paper on said formed log;

- downstream of said perforation and/or cut line, whereby it is possible to stick said tail end on the core of the new log;

- bridging said perforation and/or cut line, whereby with a single glue application it is possible to cause both closing of said web of paper on said formed log and the sticking of said tail end on the core of the new log.


 
3. Rewinding machine, according to claim 1, wherein means are provided for measuring the length of said web starting from a large roll of paper, said means for measuring driving said means for applying a measured amount of glue to achieve a measured length of said web of paper.
 
4. Rewinding machine, according to claim 1, wherein said means for applying are movable towards/away from said web of paper operated by an actuator selected from the group comprised of:

- a pneumatic actuator;

- a electric actuator;

- a hydraulic actuator.


 
5. Rewinding machine for making logs of sheet or web material, for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising:

- feeding means a web of paper along a feeding direction;

- means for perforating and/or cutting said sheet, or web, of paper adapted to make transversal perforation lines and/or clean cuts on said sheet, or web, of paper;

- a winding cradle downstream of said feeding means where said log is made by winding said web of paper about a core;

- means for introducing said core into said winding cradle;

- means for applying a measured amount of glue on a predetermined portion of said sheet, or web, of paper,

characterised in that:

- said means for applying comprises a single application element adapted to apply said measured amount of glue upstream from and/or downstream of, or bridging, said transversal perforation and/or clean cut lines.


 
6. Method for winding a sheet, or web, for making logs of sheet or web material, for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising the steps of:

- feeding said sheet, or web, of paper along a feeding direction;

- winding said web of paper about a core at a winding cradle;

- cutting or tearing the web making a formed log tail end and a head end of a new log;

- introducing a core into said winding cradle, starting winding the new log, removing the formed log.

characterised in that of providing, furthermore, the step of:

- applying a measured amount of glue on a portion of said sheet, or web, of paper, said application being carried out in a zone arranged upstream from an introducing zone of said core into said winding cradle.


 
7. Winding method, according to claim 6, wherein said application of said measured amount of glue on a portion of said sheet, or web, of paper is made in at least one among the following web zones:

- upstream from said perforation and/or cut line, said application allowing to provide, after a separation, closing said web of paper on said formed log;

- downstream of said perforation and/or cut line, said application allowing to provide, after a separation, the sticking of said tail end on the core of the new log;

- bridging said perforation and/or cut line, said application allowing to provide, after a separation, closing said web of paper on said formed log and the at the same time sticking of said tail end on the core of the new log.


 
8. Method for winding a sheet, or web, for making logs of sheet or web material, for the production of rolls of toilet paper, rolls of all purpose tissue paper for household use, non woven fabric, paper industrial rolls and the like, comprising the steps of:

- feeding said sheet, or web, of paper along a feeding direction;

- winding said web of paper about a core at a winding cradle;

- applying a measured amount of glue on said web of paper;

- cutting or tearing the web making a formed log tail end and a head end of a new log;

- introducing a core into said winding cradle, starting winding the new log, removing the formed log;

- characterised in that
said application is made at said winding cradle owing to a single application element that spreads said measured amount of glue in at least one of the following portions of said web of paper:

- upstream from said perforation and/or cut line;

- downstream of said perforation and/or cut line;

- bridging said perforation and/or cut line. 1.


 




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Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description