PLANT FOR PRODUCING AND PACKAGING OF PAPER ROLLS

DESCRIPTION

The present invention relates to a plant for the production and packaging of paper rolls, in particular rolls obtained by cutting logs of paper material.

It is known that the logs of paper material are produced by means of plants which, generally, comprise an unwinding unit with one or more unwinders on which corresponding parent reels are positioned for feeding respective plies that, once joined and possibly embossed, form a paper web that feeds a rewinder in which the logs are formed. The latter consist of a predetermined amount of paper web wrapped around a longitudinal axis generally defined by a tubular core suitably introduced into the rewinder with the paper web. The logs produced by the rewinder are conveyed to an accumulator and, from this, to one or more cutting-off machines which divide each log into several rolls of shorter length. Subsequently, the rolls coming out of the cutting-off machine are conveyed to packaging machines in which the rolls are packaged by making use of a film of plastic material, after which the individual packages are conveyed to a bundler or a cartoning machine that produces bags or boxes containing a predetermined number of packages of rolls.

Currently known systems provide for an arrangement of the packaging machines and the bundler/cartoning machines along two substantially parallel lines which require considerable space and, consequently, considerable economic investments. Furthermore, the conveyors that connect these machines create obstacles to the passage of operators between the machines, with the need to provide for elevated crossing passages which however involve serious problems of safety, fatigue and reactivity. The conveyors arranged between said machines also involve difficulties in feeding raw materials to the machines themselves. Overhead conveyors are known, which partly solve the problem of obstacles created by traditional conveyors but do not solve the problem of the overall space required to arrange the machines as previously mentioned.

A known plant is disclosed in WO2018 / 060841A1 which relates to a plant for the production and packaging of paper rolls which extends over a single work line.

US6463713B1 discloses a plant for the production of paper rolls which involves the use of conveyors for moving the paper rolls from one machine to another.

The main purpose of the present invention is to provide a production plant that allows to considerably reduce the spaces required in particular for the positioning of the packaging machine and the bundler/cartoning machines.

This result is achieved, in accordance with the present invention, by adopting the idea of providing a plant having the features indicated in claim 1. Other features of the present invention are the subject of the dependent claims.

Thanks to the present invention, it is possible to optimize the use of the spaces available in the area where the plant is located and, at the same time, it is possible to avoid the use of conveyors that prevent operators from moving freely between the machines, obtaining further advantages both in economic terms and in terms of safety, fatigue and reactivity of the operators.

These and further advantages and characteristics of the present invention will be better understood by every person skilled in the art thanks to the following description and the attached drawings, provided by way of example but not to be considered in a limiting sense, in which:

- Fig.l represents a schematic side view of a plant according to a possible embodiment of the present invention; - Fig.2 represents a schematic top view of the plant of Fig.l;

- Fig.3 represents a view similar to that of Fig.2 in which two production lines side by side are provided, each one configured as in Figs.l and 2;

- Fig.4 represents a schematic side view of a plant in accordance with another possible embodiment of the present invention;

- Fig.5 represents a schematic top view of the plant shown in Fig.4;

- Fig.6 represents a view similar to that of Fig.5 in which two side-by-side production lines are provided, each configured as in Figs.4 and 5;

- Figs. 7-17 relate to a possible way of making an integrated operating unit for cutting logs and packaging rolls and, in particular, Fig. 7 represents a schematic front view of the integrated operating unit, Fig. 8 represents a sectional view according to line A-A of Fig.7, Fig.9 represents a sectional view according to line B-B of Fig.7, Fig.10 represents a top view of the unit shown in Fig. 7, Fig. 11 represents a schematic antero-lateral perspective view of the unit shown in Fig. 7, Fig. 12 represents a detail of Fig. 11, Fig. 13 represents a schematic top view of said integrated operating unit with parts not shown in order to better highlight other parts and Figs. 14-17 show a further exemplificatory embodiment of said integrated operating unit.

Reduced to its essential structure and with reference to Figures 1-2 of the attached drawings, a plant according to the present invention consists of a production line (500) comprising a rewinder (501) which produces logs of paper material and an accumulator ( 502) which receives the logs produced by the rewinder (501) and, in turn, feeds two cutting, packing and bundling or cartoning modules (ML, MU). Said modules (ML, MU) are placed on two superimposed planes, forming a lower cutting, packing and bundling or cartoning module (ML) and an upper cutting, packing and bundling or cartoning module (MU). Each of said modules (ML, MU) comprises a cutting-off machine (503L, 503U), a packaging machine (504L, 504U) and a bundler or a cartoning machine (505L, 505U). In each cutting-off machine (503L, 503U) the logs coming from the accumulator (502) are divided into elements, or rolls, of predetermined length by means of transverse cuts sequentially performed on each log. In each packaging machine (504L, 504U) are formed packs of rolls coming from the respective cutting-off machine (503L, 503U), each pack being made up of a predetermined number of rolls wrapped by a packaging material. In each bundler or cartoning machine (505L, 505U) said packages are grouped in a predetermined number in a containing bag or carton. An embossing unit (506) can be arranged upstream of the rewinder (501 for embossing and joining a plurality of webs fed by corresponding parent reels (507A-507D) mounted on respective unwinders (508A- 508D). Immediately downstream of the accumulator (502), or in an intermediate position between the latter and the cutting-off machines (ML, MU), a trimming unit (509) can be arranged which trims the logs at their respective ends before transferring them to cutting-off machine. Alternatively, the trimming unit can be placed between the rewinder (501) and the accumulator (502). The single machines and operating units indicated above are per se known to those skilled in the art.

In accordance with the present invention and with reference to the examples shown in the attached drawings, on each of two superimposed planes downstream of an accumulator of the logs coming from the rewinder are arranged: a cutting-off machine, a packaging machine and a bundler or a cartoning machine. In other words, on each of the two superimposed planes downstream of the accumulator (502), i.e. in each of the aforementioned modules (ML, MU), there is a cutting-off machine, i.e. an operating unit configured to divide the logs into rolls having a predetermined length. In other words, in a plant according to the present invention a cutting-off machine (503L; 503U) is arranged both on a lower level (LB) and on an overlying upper level (UB). The two cutting-off machines (503L, 503U) are both fed by the accumulator (502), or by the trimming machine (509) if this unit is interposed between the accumulator and the cutting-off machine. The machines (503L, 504L, 505L; 503U, 504U, 505U) of each module (ML, MU) are easily managed by a single operator also due to the absence of conveyors placed in the spaces between these machines. In practice, the footprint of the plant is drastically reduced, while increasing its safety and reliability thanks to the absence of conveyors between the machines. Even when the system is duplicated, as in the example of Fig.3 and Fig.6, a single operator can easily manage all the machines on the same floor (LB, UB). In this case, each module (ML, MU) comprises two cutting-off machines, two packaging units or machines and two bundlers or cartoning machines.

For example, the aforementioned lower floor (LB) coincides with the floor on which the machines and operating units that provide for the production and accumulation of the logs and their eventual trimming are located.

As shown in the attached drawings, preferably said modules (ML, MU) are arranged so as to be internal to the outline of the machines and operating units arranged upstream.

To further reduce the space occupied by the plant, the cutting- off machine and the packaging machine of each module (ML, MU) can be integrated, forming a single integrated operating unit (510). With reference to the example shown in Figs. 7-17, this integrated operating unit comprises a separator device (1) adapted to distance the paper rolls (2) coming from the cutting- off machine (503L; 503U) and intended to feed a device (4 ) which forms groups or "lots" (20) of rolls destined to the packaging machine (504L; 504U). The separator device (1) separates each roll coming from an output line (LI, L2, L3, L4) of the cutting machine (503L; 503U) from the immediately following roll (2) of the same output line. In this way, each roll (2) that comes out of an exit line of the cutting machine (503L; 503U) will be spaced by a predetermined value from the roll that follows it along the same exit line. The device (4) is used to form the lots of rolls (2) aligned and placed next to each other in a predetermined number along the respective directions of origin. The packaging machine (504L; 504U) packs the rolls (2) preliminarily grouped by the device (4) that forms the lots (20).

With reference to the example shown in the drawings, the cutting-off machine (503L; 503U) is of the type comprising a plurality of horizontal feed channels (30) along which the logs (L) are made to advance in parallel rows by means of pushers (31) acting on the back of the logs and driven by annular belts or chains (32) arranged under the channels (30) and moved by a corresponding drive unit (33). Downstream of said channels (30) there are means for gripping and moving the logs (L) which, in the example shown in the drawing, consist of pairs of counter facing belts (34), with a pair of belts (34) for each channel (30). Downstream of said belts (34) there is a unit (35) for cutting the logs comprising a blade (36) and a mechanism for holding the logs during the cutting phase which, according to the example shown in the drawings, consists of a plurality of presses (37). In accordance with a procedure known per se, once the logs (L) have been loaded on the channels (30) of the cutting machine, the pushers (31) and the belts (34) in cooperation with each other determine the advancement of the logs, in steps of length corresponding to the length of the rolls (2) to be formed. At each step, the blade (36) is operated while the pressers (37) are arranged in locking position for locking the front parts of the logs (parts opposite to those subject to the action of the pushers 31) upstream and downstream of the blade (36). The actuation of the blade (36) determines the obtaining of a roll (2) from each log. For example, if the channels (30) are four in number and there is a log (L) on each channel, the actuation of the blade (36) determines the formation of four rolls (2) each time. After cutting, the presses (37) release the rolls thus formed which, pushed by the logs which in turn are made to advance one step by the pushers (31) and by the belts (34), advance to come out of the cutting machine (503L; 503U). The channels (30) in which the logs (L) are positioned are oriented transversely with respect to the plane of action of the blade (36) which produces the rolls (2) by transversely cutting the logs. The blade (36) acts in a plane orthogonal to the direction (PL) of origin of the logs (L). As shown in the diagram of Fig. 13, the rolls (2) come out of the cutting-off machine along the outgoing directions or lines (LI, L2, L3, L4) parallel to the direction (PL) followed by the logs in the channels (30). In other words, when exiting from the cutting-off machine, the rolls (2) are aligned along their respective output directions (LI, L2, L3, L4).

The mechanism controlling the stepped advancement of the logs (L) in the channels (30), which in the example described above is made by the belts (34) cooperating with the pushers (31), allows, if necessary, to interrupt the production of rolls (2) without necessarily having to stop the blade (36). In other words, since the cutting-off machine is equipped with a mechanism for moving the logs in steps, if necessary, the production of the rolls (2) can be interrupted simply by stopping the belts (34) so that the blade (36) can also continue to rotate.

In practice, said "T _t " the time that elapses between two consecutive cuts normally performed by the blade (36) and said "T _s " the time required to stop the belts (34), is: T _s <T _t . It is understood that the cutting-off machine can be equipped with any other mechanism for advancing the logs (L) in steps.

Preferably, the logs (L) are already trimmed logs, so that at the exit from the cutting-off machine (505L; 503U) there are only rolls (2) intended for packaging and not roll trims. If, on the other hand, the cutting-off machine (503L; 503U) receives untrimmed logs, it is possible arrange a known trim discarding device at the output of the cutting machine.

With reference to the example shown in the drawings, the separator device (1) consists of a plurality of conveyor belts (10) mounted downstream of the cutting station of cutting-off machine (503L; 503U), i.e. downstream of the cutting-off machine station provided with the blade (36). Each conveyor belt (10) always has an upper section in correspondence with a respective output line of the rolls (2) exiting from the cutting-off machine. Each belt (10) is wound on respective pulleys operated by a corresponding drive unit in such a way that the upper section of the same belt moves according to the exit direction (LI, L2, L3, L4) of the rolls (2). The rolls (2) coming out of the cutting-off machine can therefore be taken over by the belts (10). In practice, each roll (2), after its formation, passes on the upper section of a corresponding conveyor belt (10) detaching itself from the roll subsequently obtained from the log present on the same channel (30) of the cutting-off machine due to the movement of the respective belt (10). In this way, each roll (2) is separated from the roll that follows it and is obtained from the same log. On each conveyor belt (10) the rolls (2) advance according to their respective output directions (LI, L2, L3, L4), spaced from each other by a value connected to the speed of the belt (10) and therefore connected to the forward speed of the upper section of the latter. In other words, between each roll present on the upper section of each belt (10) and the roll that follows it and which is obtained from the same log (L) there is a gap of predetermined value. Said separator device therefore is destined to ensure that the rolls (2) of each output line (LI, L2, L3, L4) are suitably spaced from each other to allow a more effective intervention on the rolls themselves in the subsequent lots formation phase.

With reference to the example shown in Figs. 7-13, the lots (20) formation device (4) comprises a fixed horizontal surface (40) arranged downstream of the separator device (1) with respect to the direction of origin of the rolls (2). In accordance with the example shown in the drawings, said fixed surface (40) is a horizontal surface extending transversely to the belts (10) downstream of the latter.

Said fixed surface (40) constitutes an example of embodiment of a temporary slowing surface with which each roll (2) transported by the respective belt (10) interacts and on which the rolls (2) undergo a slowdown.

An operating unit (41) is mounted above the belts (10) comprising a plurality of actuators (42) on each of which several blades (43) are mounted in an annular configuration. For example, each actuator (42) is an annular track with a linear motor on which several carriages are mounted, each of which carries a corresponding blade (43). For example, each actuator (42) may be a conveyor commercially available under the trade name Beckhoff XTS series. In accordance with the example shown in the attached drawings, an actuator (42) is provided for each of the channels (30) of the cutting-off machine, i.e an actuator (42) with respective blades (43) above each of said belts (10).

Each actuator (42) has a lower forward section, opposite and parallel to the respective belt (10), along which the blades (43) move according to the direction of origin of the rolls (2), and an upper return section along which the blades (43) move in the opposite direction. On the fixed surface (40) begins the formation of groups or "lots" (20) of rolls (2), placed one behind the other without a gap. Each lot (20) is made up of a predetermined number of rolls (2) queued according to the respective directions of origin. In the example shown in Figs 8-12, each lot (20) consists of three rolls (2). Since the belts (10) carry on the surface (40) the rolls (2) produced by cutting several logs side by side in the cutting-off machine, the formation of multiple side by side lots (20) of rolls (2) can begin on this surface. The lots (20) are parallel to each other, i.e. they are positioned side by side as the logs in the cutting-off machine. Cyclically, the belts (10) convey the rolls (2) towards the surface (40), where the rolls stop immediately after the loss of contact with the belts (10) because the surface (40) is fixed. Furthermore, cyclically, when on any belt (10) there is a number of rolls (2) corresponding to a lot (20), a blade (43) of the respective actuator (42) exerts a thrust on the last roll of the lot, thus determining the compacting of the rolls of the lot (20) and the translation of the entire lot above the surface (40), to then return to the upper side of the unit (41) and re-run along the previous trajectory. Downstream of the surface (40) there is the conveyor (6), further described below, which receives the lots (20) and moves them towards the packaging machine (504L; 504U).

Depending on the packages to be made in the packaging machine provided downstream, the blades (43) can be operated in a differentiated manner above the belts (10). For example, if there are four lots (20) of rolls on the belts (10) and having to form a pack with two rows of rolls (2), two actuators (42) will have to impose on the respective lots (20) a greater sliding speed on the surface (40) to feed the conveyor (6) whose movement determines the numerosity of the pack or of the pack layer. For example, if the rolls are to be packed in the form of packs containing two lots (20) or in the form of packs formed by layers of two lots (20), two actuators (42) will be faster than the other two.

Downstream of the unit (41) that forms the lots (20) there is a conveyor (6), commonly called "bar towing", which moves the lots (20) away from the unit (41) and transports them to the packaging machine (504L; 504U) that is located downstream and receives the lots (20) by means of the conveyor (6). The latter is a known device. With reference to the example shown in the attached drawings, the conveyor (6) comprises a plurality of bars (60) oriented transversely to the direction (PL) of origin of the lots (20), spaced apart by a predetermined value form each other and constrained to two parallel annular belts (61D, 61S) located on the right and left sides (6D, 6S) of the conveyor (6) and driven by a corresponding actuator (62). Between the right and left sides of the conveyor there is a plane (P) on which the lots (20) advance pushed from the back by the bars (60). According to the example shown in the attached drawings, the belts (61D, 61S) are wound on corresponding guide pulleys arranged both on the rear side of the conveyor (6), i.e. on the side facing the unit (41), and on the front side. In this example, the actuator (62) is a gearmotor located on the right side (6D) of the conveyor (6). The gearmotor is connected to the belt (61D) by means of a first toothed belt (TD) and is connected to the belt (61S) by means of a second toothed belt (TS) driven through a shaft (63) passing transversely under the aforementioned plane (P). The belts (61D, 61S) always have a higher upper section and a lower low section with respect to the plane (P) and are longer than the latter. Therefore, the bars (60) cyclically move above and below the plane (P). When they move above the plane (P), the bars (60) push the lots (20) which, consequently, move on the plane (P) towards the packaging machine (504L; 504U) provided downstream. In their return run, having passed the front edge of the plane (P), the bars (60) move below the latter. Above the plane (P), guides can be arranged oriented according to an exit direction of the lots (20) according to a guide structure known per se.

It goes without saying that the conveyor (6) is suitably synchronized with the lots formation unit (20).

The rolls (2) produced by the cutting-off machine (503L; 503U) and obtained from the same log are spaced from each other by means of the separator (1). This operation is carried out in parallel for all rolls (2) coming out of the cutting-off machine, i.e. for all the rolls produced by cutting the logs loaded on the channels (30) of the cutting-off machine. Sequentially, on the belts (10) of the separator device (1) lots are formed consisting of a predetermined number of rolls (2) aligned according to the respective directions (LI, L2, L3, L4) of origin and placed side by side. When the predetermined number of rolls (2) forming a lot (20) is reached on any belt (10), a blade (43) of the corresponding actuator (42) intercepts the rear part of the last roll of the lot and pushes the entire lot until it enters the conveyor (6). When the blade (43) releases the last roll of the lot, a bar (60) of the conveyor (6) takes the place of the blade and the lot is brought to the packaging machine (504L; 504U) which is positioned downstream and provides packaging operations according to methods known per se. Therefore, downstream of each output line of the cutting-off machine (503L; 503U) there is never an accumulation, or stopping, of rolls (2) in a number greater than the number of rolls making up a corresponding lot.

In practice, with reference to the example shown in the attached drawings, the unit (4) is an acceleration and formation mechanism of the individual lots since the individual lots initially slow down on the surface (40) and following the intervention of the blades (43) they reach a speed corresponding to that of the conveyor (6). In other words, the rolls (2) can be subject to slowing down on the surface (40). The packaging machine (504L; 504U) that receives the lots (20) to be packaged is an operating unit known per se.

In relation to the above, the previously mentioned integrated operating unit comprises a cutting-off machine and a packaging machine connected with each other, in which:

- the cutting-off machine (503L; 503U) has a predetermined number of channels (30) in which the logs (L) are moved along a predetermined direction of advancement (PL) and a cutting unit that cuts the logs in a transverse direction with respect to said direction (PL) producing rolls (2) with a predetermined cutting rate,

- the rolls (2) produced by the cutting-off machine (503L; 503U) exit from the latter along output lines (LI, L2, L3, L4) which are equal in number to the number of said channels (30) and are each oriented parallel to said direction (PL),

- each lot (20) consists of a predetermined number of rolls (2) placed one behind the other and aligned along the advancement direction (PL) of the logs (L) from which the rolls are obtained, and in which, downstream of the cutting-off machine (503L; 503U), there are:

- a first unit (1) adapted to arrange the single rolls (2) spaced apart by a predetermined value (d) along the respective output lines (LI, L2, L3, L4), said first unit being provided with a surface ( 10) on which the rolls (2) coming out of the cutting-off (503L; 503U) are positioned one at a time and which moves them along the direction (PL) determining the detachment of each roll (2) from the one that follows it in the respective output line of the cutting- off machine (503L; 503U);

- a second unit (4), cooperating with the first unit (1), adapted to form the lots (20) by grouping a predetermined number of rolls (2) previously spaced from the first unit (1) so as to create lots (20) of rolls (2) each consisting of a predetermined number of rolls (2) placed side by side, said second unit (4) being provided with blades (43) connected to corresponding independent actuators (42) which move them along an annular path that always has a section parallel to a surface (10; 40) on which the rolls (2) can pass, so that each blade (43) is able to push the last roll of each lot to be formed and each lot from the back as the single lots (20) are formed;

- a third unit (6), positioned downstream of the second unit (4) with respect to said direction (PL), adapted to convey the lots (20) to a packaging machine (504L; 504U) that is arranged downstream and is able to receive the lots (20) formed by the second unit (4).

In this description, the terms first unit (1), second unit (4) and third unit (6) have been used to distinguish, respectively, a separator device (1), a lot forming device (4) and a conveyor (6).

Since, as previously mentioned, each blade (43) pushes the respective lots (20) towards the conveyor (6) as the individual lots (20) are formed, downstream of each output line of the cutting machine (503L; 503U) there is never an accumulation, or stopping, of rolls (2) in a number greater than the number of rolls that make up a corresponding lot.

Therefore, the cutting-off machine (503L; 503U) is integrated in the lots (20) packaging line and on each output line (Li, L2, L3, L4) there is never an accumulation, or stop, of rolls (2 ) in a number greater than the number of rolls that make up a corresponding lot and in it is possible to use a cutting-off machine in which the logs (L) are moved in steps along the respective channels, so that the cut can be interrupted without the need to accumulate rolls (2) at the output of the cutting machine itself as previously described. The belts (34) arranged upstream of the cutting station in the cutting-off machine (503L; 503U) constitute an example of embodiment of a mechanism for moving the logs (L) in steps. The separator (1) can be integrated with the cutting-off machine (503L; 503U), constituting the final output section of the latter, so that the cutting-off machine (503L; 503U) produces rolls (2) which, on each output line (LI, L2, L3, L4), are spaced apart from each other by a predetermined value (d) which allows the blade (43) of the unit (4) to act as previously described.

Therefore, it is not necessary to provide accumulation systems for lots (20) of rolls (2) upstream of the packaging machine (504L; 504U), which allows further savings in terms of space required for the plant that, consequently, can be installed in smaller spaces than those required by conventional systems. Furthermore, it is not necessary to engage the rolls (2) laterally, that is, it is not necessary to clamp them, such that the integrity of the rolls (2) is preserved.

In accordance with the embodiment shown in Figs. 14-17, the second unit (4) comprises a series of belts (400) closed in a loop along respective triangular-shaped paths, with a substantially horizontal section facing the surface (40 ) on which the lots (20) are formed, an ascending section (from right to left in the figure) and a descending section (substantially vertical in the figure) shorter than the ascending section. A predetermined number of blades (43) are applied to each belt (400) which perform the function described above. The belts (400) are individually motorized by respective electric motors (not visible in the drawings). The blades (43) are mounted at predetermined points on each belt (400). The function of these blades is identical to that indicated for the example described above. The length of the horizontal forward section of the belts (400) is less than the overall length of the ascending and descending return sections. In this example, for each line (LI, L2, L3, L4) there is a pair of parallel belts (400) with respective blades (43), the number of which will be commensurate with the overall length of the belts themselves. Furthermore, for each lot formation line there is a surface (401) for the temporary stop of the lots connected to a rotary actuator which places it in the lowered stop position and respectively in the raised position of allowed passage of the lots (20). In this example, the surface on which the lots (20) are formed consists of the fixed horizontal plane (40) arranged downstream of the belts (10) of the unit (1). Furthermore, in this example, downstream of the fixed surface (40) there is a conveyor belt (402) which acts as a bridge between the fixed surface (40) and the conveyor (6), and the surfaces (401) are arranged upstream of the conveyor (6). In the drawings, the actuators which control the rotation of the surfaces (401) are not visible and the surfaces (401) are shown partly raised and partly lowered. When they are lowered (position substantially orthogonal to the direction of movement of the rolls 2), the surfaces (401) prevent the translation of the rolls (2) towards the conveyor (6). Conversely, when they are raised, the surfaces (401) leave a gap between them and the underlying belt (402) which can be crossed by the rolls (2) directed towards the conveyor (6).

By means of said integrated operating unit, a process of forming the rolls and packaging them is carried out in which,

- using the cutting-off machine (503L; 503U), paper rolls er (2) are produced by transversely cutting logs (L) of paper material at a predetermined cutting rate and the paper rolls (2) thus produced come out of the cutting-off machine (503L ; 503U) along several parallel output lines (LI, L2, L3, L4);

- immediately downstream of the cutting-off machine (503L; 503U) each paper roll (2) is spaced by a predetermined value (d) from the paper roll that follows it in the respective output line (LI, L2, L3, L4); - on each output line (LI, L2, L3, L4) lots (20) are formed, each consisting of a predetermined number "N" of paper rolls (2) placed one behind the other by temporarily slowing down " N-l "rolls of each lot (20), using a temporary slowing down surface (40) which determines the temporary slowing down of said" N-l "rolls, and possible mutual approaching of the" N-l "rolls of the lot to the first roll if N> 1, the phase of approaching the "N-l" rolls of the lot to the first roll being performed by means of a pusher (43) which exerts a thrust on the last roll of the lot;

- each lot (20) is transferred onto a conveyor (6; 402) by means of the same pusher (43) used to form the lot;

- by means of the conveyor (6), the lots (20) are transferred to a machine (504L; 504U) for packaging the lots.

It goes without saying that, if N = 1, that is, if the lot consists of a single roll (2) intended to be individually packaged, the aforementioned approaching step operated by the pusher (43) is not foreseen. However, the pusher (43) determines the transfer of the only roll of the lot to the conveyor (6).

In the example described above it is N = 3, so on each output line (LI, L2, L3, L4) lots (20) are formed, each consisting of three paper rolls (2) placed one behind the other by temporarily slowing down two rolls of each lot (20), using the temporary slowing down surface (40) which determines the temporary slowing down of said two rolls, and the lot is definitively formed by placing the third roll next to the first two by means of the corresponding pusher (43) which exerts a thrust on the third roll of the lot.

In the integrated operating unit described above, between the cutting-off machine (503L; 503U) and the packaging machine (504L; 504U) there are no intermediate buffers of the type commonly used in traditional systems, in which large quantities of lots of rolls are accumulated upstream of the packaging machine. Furthermore, the lots (20) are formed and moved using means (which in the examples described above are the pushers 43 and the tow bars 60) acting only on the back of the paper rolls and not on the sides as envisaged in traditional systems. Therefore, the rolls (2) are not subject to lateral crushing. In the integrated operating unit described above, an effective integration of the various units of the group formed by the cutting-off machine and the packaging machine is achieved, placing the unit (1) immediately downstream of the cutting means of the cutting-off machine (503L; 503U), using the same blades (43) both to form the individual lots and to transfer the lots to the conveyor (6), and positioning the conveyor (6) immediately downstream of the unit (4) provided with the blades (43).

The present invention therefore provides a plant for the production and packaging of paper rolls obtained by cutting logs of paper material, comprising logs forming means for the production of logs of paper material consisting of a winding of a predetermined amount of paper material, cutting means for transversal cutting, rolls packaging means for making packages comprising a predetermined number of rolls and bundling or cartoning means for budling or cartoning said packages, in which the means for producing the logs comprise a rewinder (501) fed with the web of paper material wound to form the logs, in which said cutting means, said packaging means and said bundling or cartoning means are grouped into two modules (ML, MU) on two superimposed planes (LB, LU) of the plant downstream of the rewinder (501).

In accordance with a preferential embodiment of the present invention, an accumulator (502) is interposed between the rewinder (501) and the modules (ML, MU), in which the logs formed by the rewinder (501) accumulate. Furthermore, preferably, between the rewinder (501) and the modules (ML, MU) there are interposed an accumulator (502) in which the logs formed by the rewinder (501) are accumulated and a trimming machine (509) positioned downstream or upstream of the accumulator (502), in which the logs are trimmed at their respective ends.

Furthermore, in accordance with the present invention, the cutting means and the packaging means of each module (ML, MU) are preferably integrated forming a single integrated operating unit (510). For example, said integrated operating unit (510) can be made as described above.

In practice, the details of execution may in any case vary as regards the individual elements described and illustrated, without thereby departing from the idea of the solution adopted and therefore remaining within the limits of the protection granted by this patent in accordance with the attached claims.