IT202000017698A1 - REWINDER MACHINE FOR THE PRODUCTION OF ROLLS OR LOGS OF PAPER MATERIAL. - Google Patents

Description

DESCRIPTION

The present invention relates to a rewinding machine for producing rolls or ?logs? of paper material.

AND? It is known that the production of logs of paper material, from which, for example, rolls of toilet paper or rolls of kitchen paper are obtained, involves the feeding of a paper tape, formed by one or more? superimposed plies of paper, on a pre-established path along which various operations are carried out before proceeding with the formation of the logs, including a transversal pre-incision of the web to form pre-cut lines which divide it into separable sheets. The formation of the logs involves the use of cardboard tubes, commonly called ?cores? on whose surface is distributed a predetermined quantity? of glue to allow the paper tape to be glued onto the cores which are gradually introduced into the machine which produces the logs, commonly known as the ?rewinder?. The formation of the logs also implies the use of winding rollers downstream of the glue application station, which require each core to rotate around its own longitudinal axis so determining the winding of the tape on the core. The process ends when a pre-established number of sheets ? wound on? core, with the gluing of a flap of? last sheet on the underlying one of the roll so? format (so-called ?flap closure? operation). At this point, the log is unloaded from the rewinder.

EP1519886 discloses a rewinding machine which operates according to the operating diagram indicated above.

The documents US7469856 and EP 1679274 describe sizing systems for the production of logs in which the glue is applied to souls from below.

US2003/0047639 discloses a rewinder provided with a device comprising a series of nozzles placed over a path followed by the tubular cores introduced into the rewinder itself. These nozzles spray the glue onto the cores in transit along the aforesaid said path.

EP2045201 describes a rewinder for logs of paper material with a gluing device comprising a glue sprayer designed to spray the glue onto the cores in a waiting position upstream of a cradle above which the winding rollers are provided.

An essential operating condition for is there a suitable gluing of the paper tape on the cores? that the latter enter the area of the winding rollers, an area commonly known as the ?cradle? due to its shape, in correct synchronization with the passage of the paper tape, i.e. in correct synchronization with the rotation of the winding rollers. Can? However, it may happen that the cores enter the cradle area in advance, causing incorrect gluing of the paper tape with consequent production of defective logs, or even jamming inside the cradle which is not yet completely free to receive new cores.

The main purpose of the present invention ? to eliminate the aforementioned drawbacks.

Yes to this result? received, in compliance of the present invention, adopting the idea of realizing a machine having the characteristics indicated in claim 1. Other characteristics of the present invention are the object of the dependent claims. Thanks to this invention, ? possible to effectively control the entry of the cores into the winding area in correct synchrony with the passage of the paper ribbon and with the rotation of the winding rollers, avoiding both the early entry of the cores into the winding area and the rotation of the cores at the point of wait. Therefore, ? Is it possible to increase the quality? overall production of logs. Further advantages offered by the present invention are linked to the simplicity constructive and functional of the system adopted and at its particularly low cost in relation to the advantages offered.

These and other advantages and features of the present invention will be more and better understood by any person skilled in the art thanks to the following description and the annexed drawings, provided by way of example but not to be considered in a limiting sense, in which:

- Fig.1 represents a schematic side view of a rewinder in accordance with of the present invention in a roll forming operative arrangement;

- Fig.2 represents a detail of Fig.1;

- Fig.3 represents a detail of the machine of Fig.1 in a phase for pushing a core towards the winding station of the same machine;

- Fig.4 ? analogous to Fig.3 and represents the machine in an operative position for inserting the core between the winder rollers of the machine;

- Fig.5 ? an enlarged detail of Fig.4;

- Figs.6-7 are views similar to the previous ones but relating to a further embodiment of the present invention and mainly illustrating the introducer (6) and the temporary stop surface (7) for graphical simplification;

- Fig.8 represents a simplified block diagram relating to a possible control system of the actuators in a machine in conformity? of the invention.

Reduced to its essential structure and with reference to the figures of the annexed drawings, a rewinder (RW) in conformity of the present invention ? a rewinder of the type comprising:

- a station (F) for feeding the cores (1) coming from an accumulator (S), in which ? arranged and acting a rotary feeder (RF) which picks up one core (1) at a time and introduces it into a handling device (M) further described below, in which ? predisposed a device (GD) of sizing of the cores that applies a pre-established quantity? of glue on each of the cores introduced in this feed system;

- means for feeding and for transversally incision a paper tape (2) formed by one or more? superimposed plies of paper, with a series of guide (R1, R2, R3) and scoring (RC) rollers arranged along a web feed and pre-scoring path (2). These determine the guide of the tape (2) along a predefined feed path and the formation of transversal incisions which subdivide the tape itself into a succession of tear-separable sheets;

- means for winding the paper tape (2) onto a tubular cardboard core (1) in a winding station (W), with a first winding roller (R4) located downstream of said rollers (R1, R2, R3 , RC) for feeding and pre-engraving, and with two other winding rollers (R5, R6) arranged and acting in proximity? of the first winding roller (R4), the second and third winding roller (R5, R6) being arranged above a curvilinear guide (3) which, in cooperation with the first winding roller (R4), delimits a channel ( CH) downstream of the core handling device (1), said channel (CH) being crossed in sequence by the tubular cardboard cores (1) exiting said handling device (M).

The channel (CH) ? delimited above by the first winding roller (R4) and below by a concave surface (3) with the concavity? facing up. The entrance of the channel (CH) ? at the exit of the device (M) which moves the cores (1) towards the same channel.

According to a constructive scheme in itself? known, the third winder roller (R6) ? mounted on a support which allows it to be brought closer to the first roller (R4) in the initial phase of forming a log and respectively moved away as the diameter of the log being formed increases and in the phase of releasing the completely wound log (RO). In Fig.4 the arrow ?S? indicates the movement of the roller (R6) which moves away from the completed log to allow it to be released and rolled onto the outfeed plane (E).

The first winder roller (R4) also has the function of guiding the paper ribbon (2) coming from the feed and pre-incision rollers and directed to the winding station (W).

The first take-up reel (R4) ? of the type provided with nozzles (40) able to deliver compressed air towards the channel (CH) to determine the tearing of the tape (2) in correspondence with a line of incision of the tape itself when a predetermined number is wound on the core (1) of sheets, or when the log being formed has reached a diameter conforming to a desired value. A winder roller cos? accomplished ? described in EP1618057B1.

The aforesaid channel (CH), which substantially has the shape of a cradle, delimits the last section of the path followed by the paper tape (2) and also by the cores (1) directed towards the winder rollers (R4, R5, R6).

The tape (2) ? generally formed by pi? overlapping veils but pu? equally be of the single-ply type.

On the souls (1) is applied a quantity? pre-established glue that is used to adhere the paper tape (2) on the same cores (1), according to modality? known to those skilled in the art, while the same cores (1) advance along a predetermined direction (A) to reach the channel (CH). For example, the advancement of souls (1) ? obtained using a system comprising a series of fixed plates (4) side by side, with mainly vertical development, below which ? a corresponding series of motorized belts (5) is provided. The plates (4) and the underlying belts (5) delimit a path of advancement (A) of the cores (1), upstream of the channel (CH), along which path the sizing means (GD) are arranged and act. The belts (5) are closed in a loop on corresponding guide pulleys (50) connected to an electric actuator (51) and always have a substantially horizontal section (52) facing the said plates (4). The lower edge of the plates (4) is, in turn, facing the substantially horizontal section of the underlying belts (5). The belts (5) determine, in cooperation with the overlying plates (4), the advancement and rotation of the cores (1) upstream of the channel (CH). For example, the distributor (GD) comprises a set of nozzles (N) connected to a glue tank and arranged in the spaces between the plates (4).

The wrapping of the paper tape (2) on the cores (1) takes place in the winding station (W). In this station, cyclically, a pre-established quantity is wound on each core (1). of paper, after which?, while a new core (1) is introduced into the channel (CH), the tape (2) is subjected to a tension which determines its interruption at an incision line so that the head of the tape (2) interrupted sticks to the new core (1) for a new winding. The logs (RO) cos? products come out through an outlet chute (E).

The structure described above ? known to those skilled in the art. The modalities? winding of the tape (2) around the cores (1) in the winding station (W) are also? known to those skilled in the art and therefore are not described in greater detail.

It is understood, however, that within the scope of the present invention the advancement system of the cores (1) towards the channel (CH) of the rewinder, thus such as the device for applying the glue to the cores (1) or the structure of the winding means in the station (W), they can be of any other type.

At the outlet section (U) of the core handling device (M) ? an introducer (6) has been set up which is used to push the cores (1) towards the downstream channel (CH). The device?s output (M) corresponds to the channel?s (CH) input.

For example, the introducer (6) ? consisting of an arm connected to a shaft (60) with a horizontal axis (x) which, in turn, connected to a respective actuator (600). The latter is activated to rotate the introducer (6) around the aforesaid axis when a core (1) must be pushed to be introduced into the channel (CH). For example, the introducer (6) can? be formed as a multiple arm, or an arm made up of a plurality? surfaces parallel to each other and integral with the shaft (60) which determines its simultaneous rotation controlled by the actuator (600). Said surfaces are arranged on the shaft (60) so as to be able to pass freely between the spaces present between the plates (4) and the belts (5) of the core feed device upstream of the channel (CH). The tree (60) ? oriented transversely to the direction (A) of origin of the cores (1). In the example shown in the figure, the shaft (60) ? positioned below the curved guide (3). Preferably the introducer (6) has a concave front side (61) shaped to be able to act on cores (1) of different diameters. It goes without saying that the rotation of the introducer (6) around said axis (x) ? synchronized with the production of logs (RO), or rather with the cadence of introduction of the cores (1) in the channel (CH).

Advantageously, in conformity? of the present invention, at the outlet of the aforesaid core advancement system (1) ? otherwise? prepared a surface (7) for temporary stop of the cores (1) which ? in the core stop operating position when the introducer (6) is? in inoperative position (position of non-interference with cores 1) and, vice versa, ? in inoperative position (position which allows cores 1 to pass towards channel CH) when the introducer (6) is? in operative position (position in which the introducer 6 exerts a push behind the cores 1 to push them towards the channel CH).

Preferably, in correspondence with the outlet section (U) of the device (M) ? otherwise? a body (8) has been arranged which prevents the cores (1) from rotating when the same cores reach this section (U) and the upper section of the belts (5) continues to run along the direction (A). For example, the said body (8) pu? be hinged with a horizontal axis (p) parallel to the axis of the aforesaid rollers at one of its rear portions (80) so that its front part (81), or the part facing the channel (CH), rests by gravity on the cores (1) stopped by the temporary stop surface (7) in the station (U) without however preventing their transit towards the channel (CH) when the introducer (6) is? in action. In practice, the body (80) swings spontaneously on its rear part (80) around the axis (p).

It goes without saying that the movements of the introducer (6) and of the temporary stop surface (7) are synchronized.

The introducer (6) and the temporary stop surface (7) of the cores (1) can be mechanically interconnected and be controlled by a single actuator or, alternatively, they can be two non-interconnected elements and each controlled by a respective actuator.

In compliance of the example shown in Figs.1-5, the temporary stop surface (7) ? consisting of a tergal extension of the introducer (6). Thereby, ? Is it possible to use only one actuator (600) which controls the rotation of the shaft (60) and cannot? there is interference between the positions of the introducer (6) and the surface (7). If the introducer (6) ? formed by a series of arms as in the previously described example, the surface (7) can? be correspondingly defined by a series of rearward extensions of these arms.

In compliance of the example shown in Fig.6 and Fig.7, the introducer (6) ? controlled by the actuator (600), while the temporary stop surface (7) of the cores (1) ? controlled by an independent actuator (700). In this case, the temporary stop surface (7) ? defined by an end? of an arm (71) constrained to a shaft (70) which in turn ? controlled by the actuator (700). Similarly to the introducer (6), the arm (71) can? be formed as a multiple arm, or an arm made up of a plurality? surfaces parallel to each other and integral with the shaft (70) which determines its simultaneous rotation controlled by the actuator (700). Said surfaces are arranged on the shaft (70) so as to be able to pass freely between the spaces present between the plates (4) and the belts (5) of the core feed device upstream of the channel (CH). The tree (70) ? oriented transversally with respect to the direction (A) of origin of the cores (1) and, with reference to the example shown in the attached drawings, ? arranged in a lowered position and more? withdrawn from the shaft (60) of the introducer (6).

From the description above, ? it is clear that a rewinder machine for the production of logs of paper material in compliance? of the present invention? a machine comprising means for feeding a paper tape (2) along a first predefined path which ends in a station (W) for winding the tape itself, means for feeding tubular cardboard cores (1) sequentially along a second predetermined path which also ends it in said winding station (W), means (R4, R5, R6) arranged in said winding station (W) to wind the paper tape (2) on the cores (1), in which said first and second paths join at a channel (CH) upstream of the winding station (W), wherein at the entrance of said channel (CH) ? an introducer (6) configured to exert a thrust on the cores (1) in order to introduce them sequentially into the winding station (W), said introducer (6) has an operating arrangement in which it exerts said thrust on the cores (1) and an inoperative arrangement in which it does not interfere with the cores (1), and in which at the entrance of said channel (CH) ? otherwise? a surface (7) for temporary stop of the cores (1) is arranged and configured to be positioned in the operating position for temporary stop of the cores (1) when the introducer (6) is? in operational trim and, vice versa, to be in inoperative trim of non-interference with cores (1) when the introducer (6) ? in operational condition.

In a possible practical implementation of the invention, the introducer (6) and the stop surface (7) are mechanically connected to be controlled by a single actuator, for example as previously described with reference to Figs. 1-5 of the attached drawings.

In compliance In a further embodiment of the invention, as described above, the introducer (6) and the stop surface (7) are controlled by independent actuators (600, 700).

Furthermore, preferably, in the temporary stop position at the outlet (U) of the handling device (M), the rotation of the cores (1) is achieved. prevented by a body (8) arranged and acting in this position to precisely prevent the rotation of the cores (1) while the upper section of the belts (5) continues to run along the aforementioned direction (A).

In the block diagram of Fig.8, ? represented a unit? programmable controller (UE) which controls the rollers (R1), (R2), (R3), (RC), (R4), (R5), (R6) previously mentioned, the glue dispensing device (GD), the actuator (600) of the introducer (6) and the possible independent actuator (700) of the surface (7) for temporary stop of the cores (1).

In practice, the details of execution can still vary in an equivalent way for what? which pertains to the individual elements described and illustrated, without for this departing from the scope of the idea of solution adopted and therefore? remaining within the limits of the protection granted by this patent in conformity? of the following claims.

Claims (7)

1) Rewinding machine for the production of logs of paper material, comprising means for feeding a paper ribbon (2) along a first predefined path which ends in a station (W) for winding the ribbon itself, means for feeding tubular cardboard cores ( 1) sequentially along a second predetermined path which also ends in said winding station (W), means (R4, R5, R6) arranged in said winding station (W) to wind the paper tape (2) on the cores ( 1), in which said first and second paths join at a channel (CH) upstream of the winding station (W), and in which at the entrance of said channel (CH) ? an introducer (6) configured to exert a thrust on the cores (1) in order to introduce them sequentially into the winding station (W), said introducer (6) has an operating arrangement in which it exerts said thrust on the cores (1) and an inoperative arrangement in which it does not interfere with the cores (1), characterized by the fact that at the entrance of said channel (CH) ? otherwise? a surface (7) for temporary stop of the cores (1) is arranged and configured to be positioned in the operating position for temporary stop of the cores (1) when the introducer (6) is? in inoperative trim and, vice versa, to be in inoperative trim of non-interference with cores (1) when the introducer (6) ? in operational condition. 2) Machine according to claim 1 characterized in that said introducer (6) and said temporary stop surface (7) are controlled by a single actuator (600). 3) Machine according to claim 1 characterized by the fact that said temporary stop surface (7) ? formed by a rear extension of said introducer (6). 4) Machine according to claim 1 characterized in that said introducer (6) and said temporary stop surface (7) are controlled by two respective actuators (600, 700). 5) Machine according to claim 1 characterized in that said channel (CH) ? in the shape of a cradle. 6) Machine according to claim 1 characterized in that said winding means comprise a plurality of of rollers (R4, R5, R6) arranged in said winding station (W). 7) Machine according to claim 1 characterized in that, at the input of said channel (CH), ? provided a body (8) configured to prevent the rotation of the cores (1) when the temporary stop surface (7) of the cores (1) ? in operational position.