IT202100022814A1 - CORE EXCHANGE GROUP IN WINDING MACHINES - Google Patents

Description

Description of the patent for Industrial Invention entitled:

"CORE EXCHANGE GROUP IN WINDING MACHINES";

Invention sector

The invention relates to a unit for exchanging the cores of the logs being formed in winding machines.

As is known, winding machines generally include a unit for dragging a web of paper fed from a main reel and a unit for winding the web around a stick or core until a ?log? of paper of the desired diameter or length of wrapping.

At the end of winding a log, ? therefore it is necessary to perform the so-called exchange soul or to interrupt the continuity? of the veil of paper, to expel the logo already? format and start a new winding around a new core taken over by the winding unit for execution of the next cycle.

State of art

For this same purpose, machines have been known for some time which envisage the use of introduction grippers which mechanically grip the web at the winding unit by advancing at a speed of 1000 m. lower than that of the paper and of the upper winding roller with which they contrast due to mechanical interference.

This solution has the drawback that the grippers can wear out due to the mechanical contact and that, moreover, there is an impact with a roller of the winding unit with consequent vibrations and pulsating loads on the roller support bearings which can cause irregularities in the roller. on the wrapping paper veil.

In an analogous solution, the grippers are placed in interference with a pad instead of with the roller.

Also this solution has the drawback of wear of the pincers, and furthermore requires a vacuum suction device to keep the core on the pincers. From publication FI2009A000125 ? also known a rewinder machine in which the interruption of the continuity? of the veil is obtained by a difference in speed? of the web between the driving group and the winding group.

From publication FI2012A000142 ? also known a rewinder machine in which the interruption of the continuity? of the veil is obtained by means of a jet of pressurized air sent onto the paper veil.

Regardless of the mode chosen to interrupt the continuity? of the web and start a new winding, the known solutions have the drawback of not being able to control the first phases of winding of the web on the core, with the consequence that the first turns of the web on the core are irregular and accumulations of paper with thickenings that affect the regularity? of the next winding

Purpose of the invention

With the present invention it is intended to overcome the drawbacks of the solutions already notes and propose a method and an apparatus of exchange souls of high reliability? and which improves the first phases of winding the paper veil on the core.

Summary of the invention

For these purposes, yes? achieved by realizing a machine and a method for winding paper reels according to the attached claims, in which a web of paper fed by a dragging unit is wound onto a succession of cores by means of a winding unit, in which ? a core exchange channel is provided in which the cores to be wrapped, upstream of the first point of gluing to the core of the paper web, are imparted a rotary motion in accordance with the direction of advancement of the web so that the web is wound regularly ? from the first contact with the new core to be wrapped.

A first advantage of the invention consists in the fact that it is possible to control the winding right from the first stages, reducing the risks of irregularities? and non-uniformity? of the wound paper reel.

A second advantage consists in the possibility? to better adjust the flap of paper that remains between the glue line and the web? interruption during the exchange of the formed log with a core to be wrapped, and eliminate the risk of forming a ?loop? that is, a doubling of the piece of paper that wraps around the new core.

A further advantage consists in the possibility to perform, by applying a second line of glue on the core, the gluing of the end edge of the outgoing log without the aid of an external gluer.

A further advantage consists in the possibility to wrap the veil on temporary supports instead of the conventional cardboard cores. In fact said supports, typically made of plastic, thanks to the rotary motion imparted by the straps before the separation of the veil and the contact of said supports with the winding rollers normally coated with high friction material do not undergo shocks and erosions during the exchange phase and therefore they have a longer life and can be used repeatedly in a closed loop operation.

A further advantage consists in the fact that the winding of the veil on the supports or on the cores can take place even without the aid of glue.

List of drawings

These and further advantages will be better understood by any person skilled in the art from the following description and from the annexed drawings, given as a non-limiting example, in which:

- fig.1 schematically shows a machine according to the invention;

- figs. 2a-2f show in succession the phases of the first winding of a core in the exchange phase in a machine according to the invention;

- fig.3 shows a detail in three-dimensional view of the core exchange area in a machine according to the invention.

- figs. 4a-4f show in succession the phases of first winding of a core in the exchange phase in a further preferred embodiment of a machine according to the invention;

- figs. 5 and 5a respectively show a side view and a partial section in front view of the detail of a pad for interrupting the web in a machine according to figures 4a-4f.

Detailed description

With reference to the figures With reference to the figures ? described a core exchange unit of a winding machine 7 for the production of logs 8 formed by winding a continuous veil 1 of paper around hollow cylinders 3, or cores, normally made of cardboard.

The web 1 is fed by a main reel, not shown, and passes in succession through a perforating group 31 for the creation of transversal perforation lines on command, a dragging group 2 comprising upper and lower rollers 28, 29 for feeding of the web 1, and a winding unit 4 which provides for the realization of the logs 8 by winding the web on a succession of cores to be wound 3 coming from a feed of cores 10. In the example described, the winding unit comprises a upper winding 5 wrapped by web 1, a lower winding roller 16, and a pressure roller 6, all in contact with the log 8 being formed and at least one of which ? preferably motorized independently of the drive unit 2.

The pressure roller 6 ? carried by an arm 19 rotating around an axis 17 by means of an actuator member 18 (for example a linear hydraulic piston) so as to approach log 8 on command and control its winding parameters, for example diameter and softness.

Finally, downstream of the winding unit there is a chute 20 for expelling the finished log 8.

In operation, the web of paper passes through the upper and lower rollers of the dragging unit 2 preferably consisting of a smooth roller 28 and a rough roller 29, the speed? of rotation of which determines the speed? dragging and feeding of web 1 through the machine.

Immediately downstream of the dragging unit, the web passes through a core exchange channel 15 extending in the direction of transit of the cores between a section 11 of first contact of the cores with the paper web and a position P in which the increase of the web takes place. reel 8 which comes into contact with the upper winding roller 5 in correspondence with a first contact section 12 and stops in the growing position P in contact also with the lower roller 16 and with the presser 6.

Into the channel 15 flows a ramp 10 for feeding the cores 3 comprising movable shelves 32 dragged by a chain 33 and operated by a motorized pulley 21. Along the ramp 10? a gluing group 22 is also arranged for the deposition along the cores 3 of one or more? strips of glue intended to hold the initial edge of the web 1 in the subsequent wrapping around the core 3.

According to the invention, ? in correspondence with the exchange channel 15 there are means for moving the cores 3 which cause a rotation of the cores in accordance with the direction of the veil 1 and with the same speed? peripheral of the web at least when the cores 3 come into contact with the web and the paper begins to adhere to the core thanks to the glue present on them.

Advantageously, the rotation of the cores starts a uniform winding of the veil 1 on the core 3 already? upstream of the first contact with the upper winding roller and avoids the formation of accumulations of paper caused by the translation of the core 3 in the exchange channel 15.

Preferably, the movement means can comprise a distribution of belts 41 movable in contact with the cores 3 in their direction of advancement towards the upper winding roller 5.

In the example described, ? a contrast plate 40 is also provided, under which the belts 41 can slide, arranged along the approach path of the cores 3 to the winding roller 5 and positioned adjacent to the lower horizontal tangent of the upper winding roller 5.

Preferably, the belts 41 are subjected to the desired tension by pulleys 43 supported by arms 48 actuated by an actuator, for example a hydraulic actuator 49, and are moved in rotation by the roller 5 being retractably housed in corresponding circumferential grooves 42 so as to result bordering or slightly recessed with respect to the surface of the roller 5 itself (fig.5).

In the operation of the winding machine, as schematized in figures 2a-2f, when the log or reel 8 being formed has reached the desired diameter or winding length, the exchange phase begins with the introduction of a new core 3 during the winding phase ( FIG.2A).

The exchange phase? what? started and a pusher 23 starts moving by rotating around an axis 24 and comes into contact with the parked core 3 previously passed by the gluing unit 22 where it has received the glue necessary to take the paper web and start the new winding.

Advantageously, ? It is also possible to envisage that the gluing unit 22 applies two lines of glue on the core 3 suitably spaced so that the first line of glue applied is transferred to the final edge 44 of the completed log 80 allowing it to be glued onto the logo itself and the other line on the other hand, it allows the initial edge of the veil to be resumed on the core 3 to be wrapped.

In this case, the veil will be? therefore interrupted, with the means of interruption which will be better detailed later on, immediately after the application of the two lines of glue and after which part of the glue of the first line? been given to the outgoing veil. Alternatively, before the core comes into contact with the winding rollers, it is possible to envisage that the first winding of the web on the new core takes place pneumatically by means of air jets which push the web onto the core as it enters the exchange channel.

The pusher 23 takes the core from the ramp 10 (Fig. 2b) and carries it into the exchange channel 15.

With the technical solution described, when the core 3 pushed by the pusher 23 has reached the first contact section 11 with the web at the entrance to the exchange channel 15, it also comes into contact with the movable belts 41 which cause it to rotate agrees and with the same speed? peripheral of the web, (fig.2c-2d) causing the first winding of the paper 1 coming from the dragging unit, which adheres to the gluing areas already? created on core 3 by gluing group 22.

In this phase (fig.2d), ? also foreseen an interruption of the continuity? of the web, obtained by breaking the web, typically along a transversal perforation line created by the perforation unit 31.

Preferably, the phase of interruption of the continuity? of the ply is performed immediately after the first gluing of the paper on the new core being wound, so that while the final edge 44 of the paper wound on log 8 is recalled and completes the previous winding, the initial edge of the paper of the winding ? already wound on the core 3 in rotation (fig.2e).

In the example described, the web is interrupted (fig. 2d) by sending an air blade 45, a blow of air emitted towards the web from a nozzle 26 (better visible in fig. 3) located near the web. of the contrast plate 40 close to the upper winding roller 5 along its entire width which is emitted when the new core 3 blocks the web 1 against the plate 40 and sending the air blade causes a voltage which breaks the web paper.

In order to better control the exact point in which the interruption of continuity occurs? of the veil 1, the machine will be able? furthermore comprising a control of the position of the web perforation lines at least inside the channel 15 between the dragging group 2 and the winding group 4, associated for example with the control of the rotation of the groups 2, 4 themselves.

The breaking phase of the veil can? be performed according to different principles and techniques from the use of an air knife as described above, for example by mechanically inducing a state of tension in the web at the end of the winding phase, by means of a braking of the web 1 or a positive differential of the speed? movement of the web between the winding group and the dragging group which induces a state of tension in the paper web.

By way of example of embodiment, in figures 4a-4f ? schematized the succession of the core change phases in an embodiment of the machine which provides for the mechanical blocking of the web upstream of the breaking point, as better illustrated in figures 5, 5a.

In this embodiment, when the log or reel 8 being formed has reached the desired winding diameter or length, the exchange phase begins with the introduction of a new core 3 during the winding phase (FIG.4a).

The exchange phase? what? started and a pusher 23 starts moving by rotating around an axis 24 and comes into contact with the parked core 3 previously passed by the gluing unit 22 where it has received the glue necessary to take the paper web and start the new winding.

The pusher 23 takes the core from the ramp 10 (Fig.4b) and carries it into the exchange channel 15.

When the core 3 pushed by the pusher 23 has reached the first contact section 11 with the web at the entrance to the exchange channel 15, the movable belts 41 cause it to rotate together and with the same speed. peripheral of the veil, causing the first winding of the paper 1 coming from the dragging group, and adheres to the gluing areas already? created on core 3 by gluing group 22.

In this phase (fig.4c), ? also foreseen an interruption of the continuity? of the web, obtained by breaking the web typically along a transversal perforation line created by the perforation unit 31.

Also in this case, as for the embodiment of figures 2a-2f, preferably the step of interrupting the continuity? of the web is performed immediately after the first gluing of the paper on the new core being wound.

In the example described, the interruption of the veil is performed (fig. 4c ) by means of the temporary contrast with the veil and with the plate 40 of a pad 46 arranged at the end? of the pusher 23 (better visible in fig.5a) for all its width of the veil and which can? be advantageously provided with grooves 48 in correspondence with the belts 41, so as to compress and block the veil 1 without interfering with the rotation of the belts themselves.

Due to the blockage of the web, the tension created by the downstream drag causes it to break.

Also in this case, as for the example of fig.2a-2f, in order to check the interruption point of the continuity? of the veil 1, the machine will be able? including a control of the position of the perforation lines of the web.

Once the veil has been interrupted, the final edge 44 of the 80 format logo, already? glued, is wound up and adheres to the concluded winding, while the front edge adheres to the new reel (fig.4d) and enters the winding unit 4 which winds the web around the new log 8 being processed (fig.4e) while the wrapped log 80 is sent to the subsequent workings and a new core 3 ? waiting on ramp 10 (fig.4f).

The invention achieves important advantages mainly due to the fact that the controlled movement of the core entering the exchange channel upstream from the start of the winding allows to synchronize the rotation of the core entering with the web and to control the movement and the position of the core both in the actual winding phase (avoiding the formation of "loops" and unevenness of the web) and in the exchange phase, for example being able to apply the lines of glue having greater certainty on their position at the time of change coil.

The present invention ? been described according to preferred embodiments but equivalent variants can be devised without departing from the scope of protection of the invention.

Claims (13)

1. Winding machine for the production of reels (8) of paper, comprising, a feeding (10) of a succession of cores (3) to be wrapped with a veil of paper (1) at the input, a winding assembly (4) provided with at least one winding roller (5) for forming a reel (8) by winding the web (1) around said core (3), an exchange channel (15) extending in a transit direction of the cores (3) between a section (11) of first contact with said web (1) and a growing position (P) of the reel (8) placed downstream of a first contact section (12) of the core (3) with said winding roller, characterized in that it comprises movement means (41) for imparting to said core (3) a rotary motion in accordance with said advancement direction of the veil (1) at least starting from said section (11) of first contact with the veil (1 ). 2. Machine according to claim 1, comprising a drawing unit (2) for the incoming paper veil (1). 3. Machine according to claim 1 or 2, wherein said movement means (41) comprise a distribution of belts (41) movable in a direction concordant with the direction of the web (1) and extended in contact with said core (3) at least between the inlet section (11) of the core (3) in the channel (15) and the first contact section (12) with the winding roller (5). 4. Machine according to one of the preceding claims, wherein ? also provided is a contrast plate (40) arranged along the approach path of the cores (3) upstream of the first contact section (12) with the winding roller (5), below which the belts (41) can slide ). 5. Machine according to one of the preceding claims, wherein the belts (41) are moved by the winding roller (5). 6. Machine according to one of the preceding claims, wherein the belts (41) are housed in a retractable way in corresponding circumferential grooves (42) of the roller (5) so as to result in an overflow or slightly recessed position with respect to the surface of the roller (5) itself . 7. Machine according to one of the preceding claims, comprising means for interrupting the continuity? of the veil (1) operating inside the channel (15) between said input section (11) and said first contact section (12). 8. Machine according to claim 7, wherein said continuity interruption means? of the veil are pneumatic means comprising a nozzle (26) placed near the of a contrast plate (40) and connected to a source of compressed air to send a blade of air (45) towards the web (1) when a core (3) blocks the web (1) against the plate (40) in such a way that the air blade causes a tension that breaks the paper veil. 9. Machine according to claim 7, wherein said continuity interruption means? of the veil are mechanical means of temporary contrast against the veil (1) and a contrast plate (40). 10. Machine according to claim 9, wherein said contrasting mechanical means comprise a pad (46) arranged at the end? of a pusher (23) arranged to take the cores (3) from the feed (10) and bring them into the exchange channel (15) in contact with the movable belts (41). 11. Machine according to claim 10, wherein said pad is provided with grooves (48) in correspondence with the belts 41, so as to block the veil (1) against the plate (40) without interfering with the rotation of the belts. 12. Machine according to one of the preceding claims comprising a gluing unit (22) arranged upstream of the inlet section (11) for depositing one or more glues along the cores (3). lines of glue intended to hold the initial edge of the web (1) being wound and/or to be transferred to the final edge of the web already? wrapped around the finished logo (80). A method for producing coils (8) of wound paper in a wrapping machine, comprising, a feed of a veil of paper (1) at the input, a feeding (10) of a succession of cores (3) to be wrapped with said veil, a winding assembly (4) provided with at least one winding roller (5) for forming a reel (8) by winding the web (1) around said core (3), an exchange channel (15) extending in a transit direction of the web (1) between said driving group (2) and said winding group (4), comprising a first contact section (11) of said core (3) with said veil (1) and a first contact section (12) of said core (3) with said winding roller (5), in which ? provided for imparting to said core (3) a rotary motion in accordance with the direction of advancement of the veil (1) at least starting from the first contact section (11) of the core (3) with the veil (1).