CN117693481A

CN117693481A - Guiding system for guiding a paper web

Info

Publication number: CN117693481A
Application number: CN202280048753.2A
Authority: CN
Inventors: F·佩里尼
Original assignee: Futura Corp
Current assignee: Futura Corp
Priority date: 2021-07-16
Filing date: 2022-06-28
Publication date: 2024-03-12
Also published as: WO2023286093A1; IT202100018878A1

Abstract

A guiding system for processing a web of paper material, comprising: -a gripping device (1) configured to engage a web (W) of paper material to control its movement according to a predetermined advancing direction (WF); -a structure (2) for supporting the clamping device (1); -hooking means (4) suitable for temporarily hooking the lateral edges (SW) of the web (W), said hooking means being arranged downstream of the gripping means (1) with respect to the aforesaid advancing direction (WF); wherein-said hooking means (4) comprise a flexible member (40), the flexible member (40) being equipped with a tip (46) adapted to engage a lateral edge (SW) of the web (W), the flexible member (40) being mounted on a support (41) movable between a hooking position and a non-operating position.

Description

Guiding system for guiding a paper web

Technical Field

The present invention relates to a guiding system for processing a web of paper material.

In particular, the system for processing webs of paper material according to the invention can be used to guide such webs in so-called "paper converting" lines in which the web unwound from the parent reel feeding them undergoes a series of conversions that determine the production of paper material articles, such as toilet or kitchen rolls and more generally so-called "sanitary" items, including handkerchiefs and napkins.

Background

As is known, paper processing facilities generally comprise a series of machines and devices arranged according to an operative path followed by one or more webs of paper material, which are subjected to operations such as embossing, printing of logos or decorative designs, rolling or folding, and finally packaging of the finished product.

US5255602 describes a web stretching system for use in a printer in which strips of "Velcro" are applied across the entire front edge of the web transversely to the stretching direction.

Some operations, such as stretching and preliminary preparation of the web unwound from the parent reel feeding them, are carried out almost entirely manually, which means that highly specialized personnel are required and involve risks for the safety of the operators themselves. For example, in the phase of preparing the web for drawing in or in the event of breakage of the web in use, the free front edge of the web wound on the parent reel is manually truncated to obtain a portion of rough triangle, which is intended to be knotted onto the drawing-in belt, and then the web is guided along the path described above, to allow the equipment and machines constituting the paper processing facility to use it. However, depending on the weight of the paper and the experience of the operator, this operation can be difficult and sometimes gives different results and there is a risk of unnecessary breaks in the paper and subsequent repeated operations being required. Furthermore, during these phases, the operator must stay for a long time in areas where there is an essential risk to his safety.

Disclosure of Invention

The main object of the present invention is to eliminate or at least to greatly reduce the above-mentioned drawbacks.

According to the invention, this result is achieved by the idea of providing a guiding system for processing a web of paper material, which guiding system has the features indicated in claim 1. Other features of the invention are the subject of the dependent claims.

Thanks to the invention, the preparation of the paper material web used in the paper processing facility can be simplified, reducing the degree of experience required by the operator, while ensuring its correct execution, regardless of the paper weight. Furthermore, the preparation operations of the paper material web can be performed in an automatic mode, which ensures that the predetermined preparation criteria are always met, and allows the operator to supervise these operations from the outside (i.e. outside the area occupied by the system). In addition, the guiding system according to the invention has a relatively simple mechanical structure.

Drawings

These and other advantages and features of the present invention will be better understood by each of the skilled in the art from the following description and drawings, which are provided by way of example and not to be considered limiting, in which:

fig. 1 depicts a schematic side view of a guiding system according to the invention in an initial stage of preparing a web of paper material;

FIG. 2 is a schematic front view of the system depicted in FIG. 1;

FIG. 3 is a schematic side view of the system of FIG. 1 in a subsequent operating step;

FIG. 4 is a schematic front view of the system depicted in FIG. 3;

FIG. 5 is a schematic front view of the system shown in FIG. 1 in an operating step subsequent to that shown in FIG. 3;

FIG. 6 is a schematic front view of the system depicted in FIG. 5;

figure 7 depicts a detail of figure 1;

FIG. 8 depicts a further detail of FIG. 1;

figure 9A shows a detail of figure 1, showing a possible embodiment of the clamping device (1) when the cutting device is in the operating position;

FIG. 9B depicts a detail of FIG. 9A, with some parts omitted to better highlight other parts;

fig. 10A-10C are cross-sectional views of possible embodiments of the hooking strip (40);

fig. 11A-11C are schematic side views of a release mechanism releasing a web from a hook tape;

11D-11F are partial front views of the release mechanism of FIGS. 11A-11C;

fig. 11G is a schematic side view of another embodiment of a mechanism for releasing a web from a hook tape;

figures 12A-12E show different views of the frame (41);

13A-13C show three perspective views of the cutting device of the system depicted in the previous figures;

fig. 13D is a schematic longitudinal section of the cutting device shown in fig. 13A-13C;

fig. 14 is a simplified block diagram relating to a possible automatic control mechanism for controlling the operating units of the system depicted in the previous figures;

fig. 15 is a schematic plan view of a possible pre-cut profile of a web of paper material;

fig. 16 is similar to fig. 4, but it relates to the case in which the front cut profile of the web is made as schematically shown in fig. 15.

Detailed Description

Simplified to its basic structure and with reference to fig. 1-14, a guiding system for processing a web of paper material according to the present invention comprises:

-a gripping device (1) configured to engage a web (W) of paper material wound on a Parent Reel (PR) and to control its movement along a predetermined advancing direction (WF);

-a structure (2) on which the gripping device (1) is supported at a predetermined distance (d) by a support (3), the support (3) being configured to support the Parent Reel (PR) in a predetermined position (a), wherein the same reel (PR) is rotatable about its own longitudinal axis;

-hooking means (4) suitable for temporarily hooking the lateral edges (SW) of the web (W), arranged downstream of the gripping means (1) with respect to the aforesaid advancing direction (WF);

-cutting means (5) suitable for cutting the web (W) arranged upstream of said hooking means (4) with respect to the aforesaid advancing direction (WF).

Preferably, the cutting device (5) is arranged in the vicinity of the clamping device (1).

Referring to the example of embodiment shown in fig. 1-14, the gripping device (1) comprises two parallel rollers (10, 11) oriented orthogonally to the advancing direction (WF), which are configured and controlled for forming a pressure nip (nip) through which the web (W) can pass. The first roller (10) is in a fixed position and is motorized, while the second roller (11) is mounted idle on a support arm (12), which support arm (12) can be moved to the first roller (10) and away from the first roller (10) by means of an actuator (13), which actuator (13) controls their rotation about an axis (H) parallel to the axis of the same roller (10, 11). Thus, when the second roll (11) approaches the first roll (10) by means of the rotation of the arm (12) controlled by the actuator (13), said pressure nip is formed and the web (W) is dragged by the rolls (10, 11) in the advancing direction (WF). Conversely, by moving the second roller (11) away from the first roller (10), the pressure nip is removed and the rollers (10, 11) no longer exert a dragging action on the web (W). Preferably, the second roller (11) is a roller with a rubber coating. For simplicity, in the figures, the means (100) for controlling the rotation of the roller (10) about the respective axis are shown only in fig. 14.

Referring to the embodiment shown in the drawings, the structure (2) supporting the gripping device (1) comprises a metal frame with two uprights (20), the gripping device (1) being connected to the two uprights (20) at a predetermined distance from the base (B) of the system. In this example, the aforementioned rollers (10, 11) are arranged orthogonally between the uprights (20) of the structure (2), and the arm (12) of the second roller (11) is hinged with a horizontal axis on the upper side of the uprights (20). Furthermore, the connecting rails (21) are arranged between the uprights (20) such that the structure (2) as a whole has a substantially portal shape.

With reference to the example of embodiment shown in fig. 1-14, the support (3) for the Parent Reel (PR) is a support known per se, comprising two sides (30) between which a plurality of belts (31) are arranged to close in a loop on respective guiding and dragging rollers (32). In fact, the support (3) is a bracket in which the Parent Reel (PR) is positioned and in which the appropriately motorized belt (31) determines the rotation of the Parent Reel (PR), this rotation being constrained (33) by two coaxial pins arranged in the above-mentioned position (A) on its longitudinal axis. When the belt (31) is actuated, the parent spool (PR) rotates about the pin (33) due to its contact with the belt itself. As previously mentioned, the actuation and control of such a support as a belt (31) is known per se to the person skilled in the art.

With reference to the embodiment shown in the figures, the lateral hooking means for the web (W) comprise a hooking belt (40) mounted on a frame (41) movable between a non-operative position spaced apart from the lateral edge (SW) of the web (W) and an operative position close to said edge. The lateral edges (SW) of the strip (W) are the longitudinal edges of the latter.

In fig. 1, 2, 5 and 6, the frame (41) is in the non-operative position, whereas in fig. 3 and 4, the frame (41) is in the operative position for hooking the lateral edges (SW) of the web (W). For example, the frame (41) is formed by a plate hinged on its underside (410) about a horizontal axis (H4) oriented orthogonal to the uprights of the structure (2). The axis (H4) is formed by connecting the underside (410) of the frame (41) to a support base formed by two plates (B4) aligned along a direction orthogonal to the uprights (20) of the structure (2) by means of respective hinges (C4). In the exemplary figures, the frame (41) is hinged to the left upright (20) of the structure (2). The double arrow "R4" in fig. 12E indicates the rotation of the frame (41) about the axis (H4). The rotation of the frame (41) about the axis (H4) is controlled by an actuator (A4) placed on one side of the frame (41). The hooking belt (40) is a belt actuated by a corresponding electric actuator (42) integral with the frame (41). In the exemplary figures, the actuator (42) of the control band (40) is integral with the lower portion (410) of the frame (41). Since the actuator (42) is integral with the frame (41), the belt is controlled by the actuator (42) even when the frame (41) rotates about the shaft (H4). The hooking strip (40) extends along a closed loop (P4) having a first descending branch (PH) along which the strip hooks the lateral edge (SW) of the web (W) and a second branch (PT) along which the web (W) hooked to the strip (40) is guided towards the exit area (PE). Referring to the exemplary figures, the first branch (PH) of the circuit (P4) is oriented like the moving frame (41), while the second branch (PT) passes under the support (3) of the Parent Reel (PR). The hooking belt (40) is guided on a plurality of pulleys (40P) arranged on the inner side (41N) of the frame (41). Thus, along the branch (PH) of the circuit (P4), the belt (40) undergoes the same movement applied to the frame (41). Thus, when the frame (41) approaches the lateral edge (SW) of the web (W), the branch (PH) of the loop followed by the belt (40) also approaches the lateral edge of the web, and vice versa, when the frame (41) moves away from the lateral edge (SW) of the web (W), said branch (PH) also moves away from the lateral edge of the web.

The first branch (PH) of the loop (P4) constitutes the junction branch of the lateral edge (SW) of the web (W).

The second branch (PT) of the loop (P4) is an extension of the first branch (PH) which directs the lateral edge (SW) of the web (W) towards a downstream release Point (PE) distant from the system area in which the hooking means are arranged.

In the example shown in the figures, the second branch (PT) is substantially horizontal, but it will be appreciated that the orientation of this branch (PT) may vary, depending on the arrangement of the machine or equipment in which the web is used.

The hooking belt (40) has an inner side (40N) facing the support (3) of the Parent Reel (PR), i.e. facing the direction from which the web (W) comes, and an opposite outer side (40E).

The arrow in fig. 8 shows the movement of the belt (40) along the path (P4).

The spikes (46), i.e., protrusions, of the belt (40) may be evenly distributed throughout the length of the belt itself or may be disposed on selected sections of the belt itself.

In order to facilitate hooking of the web (W) by the belt (40), a movable presser (42) is advantageously provided, which presses the edge (SW) of the web (W) against the inside of the hooking belt (40) when it is necessary to perform the web hooking phase. For example, the mobile presser (42) comprises a brush rotating about a horizontal axis (K) orthogonal to the frame (41) and mounted on a respective support arm (43), the support arm (43) being in turn hinged to the frame (41) with its axis (J) parallel to the axis of the brush and controlled by a pneumatic actuator (44) which determines the movement of the brush to and from the hooking strip (40). Alternatively, the pressing member comprises a rubber wheel (not shown in the figures) arranged similarly to the brush described previously.

In a possible embodiment, the hooking belt (40) is provided with a protrusion suitable for piercing the web (W) during said hooking step. For example, as shown in fig. 10A, the belt (40) is a belt having a rectangular cross section, on which the nail portions (46) are inserted at a predetermined distance from each other, the tips of the nail portions (46) protruding beyond the inner side (40N) of the belt. Alternatively, the belt (40) is a longitudinally grooved belt with the spike (46) positioned in the center of the longitudinal groove as shown in fig. 10B. Also alternatively, the belt (40) may have a trapezoidal cross section, with the main base forming the inner side (40N) of the belt, as shown in fig. 10C, provided with spikes similar to the other examples described. In fact, the hooking strip (40) is a flexible element equipped with hooking protrusions or points (46), which hooking protrusions or points (46) are able to hook to the web (W) when the phase of hooking the lateral edges (SW) of the web is activated.

The spikes (46) or protrusions of the belt (40) may be evenly distributed over the entire length of the belt itself or may be disposed on selected sections of the belt itself.

Preferably, the guiding system according to the invention further comprises a mechanism for releasing the web (W) from the hooking means (4). For example, when the hooking means comprise the previously described belt (40) provided with spikes, the release mechanism may be of the type shown in fig. 11A, 11B or 11C.

The release mechanism shown in fig. 11A includes two curved bars (45) that are parallel to each other and spaced apart by a sufficient amount to allow the spikes (46) to pass in the space created between the bars (45). The latter forms a bridge between the output side (PE) of the path (P4) and a second belt (400), the second belt (400) being of similar construction to the belt (40), and also being provided with points or protrusions suitable for penetrating the web (W) to engage it on the same Side (SW) as the first belt (40). To facilitate transfer of the belt (W) on the second hook belt (400), a pulley (401) with a central groove (402) may be positioned on the end of the rod (45), i.e. above the inlet side of the second hook belt (400). In fact, the edge of the web hooked to the spikes (46) of the first hooking belt (40) is on the bars (45), while the spikes (46) pass through the spaces between the bars (45) and, while facing the machine in which it is used, the edge of the web (W) now unhooked from the belt (40) is hooked by the spikes of the second belt (400). The pulley (401) makes it easier to hook the side edges of the web (W) to the second belt (400). Fig. 11A shows a pulley (40E) for guiding the belt (40) corresponding to the aforementioned output side (PE) and a pulley (405) for guiding the belt (400) at the corresponding entrance side.

The release mechanism shown in fig. 11B includes a brush (47) located on the output side (PE) of the loop (P4) and aligned with the belt (40) provided with spikes. The brush (47) rotates in the direction indicated by the arrow depicted on the same brush in fig. 11B, so it acts in such a way that the lateral edge of the web is removed from the spikes of the belt (40) guiding it towards the belt (400) located downstream, which has the same configuration as previously described with reference to the example of fig. 11A. Also in this example, the pulley (401) of the previous example may be used, which is arranged to form a bridge between the brush (47) and the pulley (405) of the guide belt (400).

The release mechanism shown in fig. 11C comprises a set of nozzles (RN) arranged on the outlet side (PE) of the circuit (P4) so as to blow air upwards, and on the opposite side the previously described pulley (401) rotating in a direction coinciding with the direction followed by the web strip (W), forming a bridge between the aforesaid strip (40) and the strip (400).

The release mechanism shown in fig. 11G includes a brush (406) disposed above the outlet side (PE) of the path (P4). The belt (40) and the belt (400) are located on two paths side by side and share a pulley (407) positioned on the output side (PE). The belt (400) downstream of the belt (40) has the same configuration as described previously with reference to the example of fig. 11A. The brush (407), like the pulley (402) of the example shown in fig. 1B and 11C, pushes the paper web onto the tip of the belt (400), whereby the belt (400) takes over it.

In all of the examples described above, the second belt (400) directs the web (W) to a final release point downstream.

Referring to the example of embodiment shown in the drawings, the cutting device (5) is arranged above the clamping device (1) and comprises a blade (50) mounted on a moving support (51), such as a carriage, the moving support (51) being controlled by an electric motor (52) by means of a belt (53), the moving support (51) being connected to the belt (53). The moving support (51) moves on a guide (2G) formed on a crosspiece (21) of a column (20) of the connection structure (2). A pulley (5Z) is mounted on the same beam (21), and a belt (53) is guided on the pulley. The blade (50) is mounted on a rod (5L) controlled by a corresponding pneumatic actuator (55) arranged on the mobile support (51), which allows the blade to move reciprocally with respect to the gripping device (1). With reference to the example shown in the figures, the respective end of the rod (5L) is hinged on the free end of the actuator (55). The blade (50) is hinged on the other end of the rod (5L) by means of a respective hinge (5K), free to rotate about its own axis. The rotation axis of the blade (50) and the axis of the hinge (5P) of the connecting rod (5L) and the actuator (55) are parallel to each other and orthogonal to the rod portion of the actuator (51). The actuator (55) is fixed on one side of the arm (54), and the lever (5L) is pivoted on a front portion (540) of the arm (54) by means of a hinge (5H) whose axis is parallel to the rotation axis of the blade (50). The hinge (5H) is at an intermediate position between the hinge (5P) and the hinge (5K). The arms (54) have, on their front side (540), a lower cylindrical appendix (5M) oriented towards the rear side of the same arm (54) and inserted into the tubular bush (5N). The latter is the front attachment of the mobile carriage (51). The blade can thus be translated along the guide (2G) by means of the mobile support (51), and in addition, the blade can be reciprocally moved by means of the actuator (51) with respect to the fixed roller (10). In fact, the group formed by the actuator (55), the arm (54), the rod (5L) and the blade (50) can translate along the guide (2G) and be constrained to the mobile support (51) controlled by the motor (52). Furthermore, the same assembly is free to rotate about the axis of the bushing (5N).

By suitably combining the translation speed of the carriage (51) and the rotation speed of the fixed roller (10), the web (W) can be cut transversely according to a profile having a predetermined shape. For example, by setting a constant rotational speed of the fixed roller (10) and a constant translational speed of the carriage (51), on the side of the web (W) intended to be hooked by the hooking means (4), the web will be cut into triangular flaps (TW), as schematically shown in fig. 4 and described further below. Another method of controlling the cutting device is described below.

With reference to the application examples shown in fig. 1-6, possible operating cycles of the guidance system described above are as follows.

As shown in fig. 1, in a first phase, the operator inserts the free front edge of the web wound on a Parent Reel (PR) through a clamping device (1), the Parent Reel (PR) being arranged on a support (3) and the belt (31) being activated to rotate the parent reel at a predetermined speed, allowing the web (W) to unwind. The unwinding phase is actuated by the operator himself through a control panel (not visible in the figures). At this stage, the gripping device (1) is actuated, i.e. the roll (11) is closer to the roll (10) so that the web (W) is in the nip formed by the same rolls (10, 11), the rolls (10, 11) controlling their advance in the direction (WF). An optical sensor (101) shown only in the diagram of fig. 14 is arranged and acts on the side of the system opposite to the side on which the hooking means (4) are mounted, which optical sensor (101) detects whether the web (W) has passed the gripping means (1) and is spread completely over its entire width (WW), as shown in fig. 2. At this stage, the free Front Edge (FE) of the web (W) is collected on a tray (V) arranged below the gripping device (1). The blade (50) is in the non-operative position spaced from the roller (10) and arranged on the side of the guide (2G) closest to the hooking means (4), i.e. on the left side of the structure (2), as shown in fig. 2, with reference to the exemplary figures.

Subsequently, the cutting device (5) is actuated, moving the blade (50) towards the roller (10), and the motor (52) is actuated, which determines the translation of the carriage (51) towards the opposite side of the structure (2), i.e. to the right with reference to fig. 4, wherein arrow "F5" indicates the translation of the carriage (51) in this phase of the process. In this way, the blade (5) also translates like the carriage (51). Thus, the web (W) is cut, producing flaps with a substantially triangular portion (TW) corresponding to the side of the web (W) intended to be hooked by the hooking means (4), and at the end of the cutting phase thus performed, the flaps (DW) will disengage from the Parent Reel (PR), be collected on the pallet (V) and be recovered. At the same time, the device (4) for hooking the web (W) is activated, the frame (41) rotates about the axis (4H), which determines the overlap of the Path (PW) followed by the lateral edges (SW) of the web (W) to the branch (PH) of the loop (P4), and the brush (42) is pushed towards the web (W). In this way, the lateral edges (SW) of the web (W) will be hooked to the belt (40). Referring to fig. 4, the lateral edge (SW) hooked by the belt (40) is the left edge of The Wing (TW). As the belt (40) is driven, the edge (SW) is guided along the path followed by the same belt (40) to the exit Point (PE) of the path (P4). Then, after a predetermined time sufficient to ensure hooking of a predetermined length of the lateral edge (SW) of the web (W) onto the belt (40) has elapsed after actuation of the hooking means (4), the brush (42) and the frame (41) return to their initial non-operative positions, as shown in fig. 5 and 6. Similarly, the roller (11) and the cutting device (5) return to their respective initial non-operative positions. As a result, the lateral edges (SW) of the web unwound from the parent reel will no longer hook to the belt (40) and will move along a path parallel to the section (PT) of the same belt. At this point, the web can be unwound from the parent reel at a higher unwinding speed determined by the speed of the downstream machine using the web and the belt (31) controlling the rotation of the Parent Reel (PR). In fig. 6, the cutting device (5) has reached the end-of-travel position (right in the drawing) and the leading edge (AW) of the web (W) has been cut straight correctly.

Considering that the lateral edges of the web are generally eliminated and discarded before the manufacture, the perforation caused by the hooking belt (40) on the lateral edges (SW) of the web (W) does not lead to a significant reduction in the quality of the finished product: for example, if the web (W) is used to produce logs from which toilet paper rolls are obtained, the logs are subjected to a finishing operation comprising cutting end portions. And in any event, the log normally produced in the first batch is discarded.

The above-described system thus makes it possible to guide a paper web along a predetermined path by engaging one side of the paper web in an initial stage of the guiding process, automatically and extremely simply without the intervention of specially trained personnel.

A programmable control unit connected to the actuators of the various operating units of the system described above allows to automatically perform the operations described above. The simplified block diagram of fig. 14 depicts a possible configuration of a control mechanism comprising a programmable control Unit (UE) connected to a sensor (101) and coupled to actuators of the gripping device (1), the belt (31), the hooking belt (40) and the cutting device (5).

In the previous description of a possible operating cycle of the machine, it has been illustrated the case where the cutting device (5) produces substantially triangular flaps (TW) on the belt (W), provided that the rotation speed of the fixed roller (10) and the translation speed of the mobile support (51) are constant. However, the cutting device (5) may produce cuts of the web (W) having a profile different from the triangular profile (TW). For example, the incision made by the device (5) can produce on the web (W) a tab having a profile defined by two consecutive cutting lines with different inclinations, as schematically illustrated in figures 15 and 16. In this case, by rotating the fixed roller (10) at a constant speed, the mobile support (51) initially translates at a first speed that produces the cutting line (T1), then translates at a second speed that is higher than the first speed to produce the cutting line (T2), and finally translates at a third speed that is intermediate between the first speed and the second speed to produce the cutting line (T3). As shown in fig. 15, the cut lines (T1, T2, T3) produced on the web (W) are continuous and have different inclinations with respect to the Cross Direction (CD) of the web (W). The broken line portion (DW) in fig. 15 represents the web (W) portion separated by the cut.

Whichever cutting profile is chosen, the front portion of the web (W) to be hooked is given a predefined, precise and programmable shape, which greatly reduces the possibility of the web getting stuck downstream of the lateral hooking zone, independently of the sheet grammage.

The aforementioned cutting device may be omitted by accepting that the hooking of the paper web is performed in case the front edge is not cut as described above, or in case the front edge is cut or prepared manually, possibly even before positioning the reel in the machine in which it is used.

As is apparent from the description provided, more generally, the system according to the invention comprises:

-a gripping device (1) configured to engage a web (W) of paper material to control its movement according to a predetermined advancing direction (WF);

-a structure (2) for supporting the clamping device (1);

-hooking means (4) suitable for temporarily hooking the lateral edges (SW) of the web (W), said hooking means being arranged downstream of the gripping means (1) with respect to the aforesaid advancing direction (WF);

and is also provided with

-said hooking device (4) comprises a flexible member (40) provided with a tip (46) suitable for engaging a lateral edge (SW) of the web (W) while the same flexible member (40) moves along a path (P4), the flexible member having a first section (PH) and a second section (PT), the flexible member (40) being mounted on a support (41), the support (41) being movable between a hooking position in which the first section (PH) overlaps the Path (PW) followed by the lateral edge (SW) of the web (W) and a non-operating position in which said first section (PH) is spaced from the Path (PW) followed by the lateral edge (SW) of the web (W) and the second section (PT) of the path (P4) is a section along which the web (W) moves away from the point of hooking.

Preferably, the system comprises cutting means (5) suitable for cutting the web (W) transversely, which are arranged upstream of said hooking means (4) with respect to the aforesaid advancing direction (WF), said cutting means being constrained to respective movable supports (51), the movable supports (51) moving them transversely to the advancing direction (WF) of the web (W) and being actuated when the hooking means (4) engage the lateral edges (SW) of the web (W).

According to a preferred embodiment of the invention, the flexible member (40) is a tape and the tip (46) is a spike inserted into the tape.

The belt (40) may be a belt with a rectangular cross section, or a belt with longitudinal grooves, or a belt with a trapezoidal cross section.

The tips (46) may be distributed over the entire length of the belt (40) or, alternatively, they may be distributed over predetermined portions of the belt (40) so as to form portions of the hooking surface.

Preferably, the hooking means (4) comprise a presser (42) acting on the lateral edge (SW) of the web (W).

According to a preferred embodiment of the invention, the presser (42) comprises brushes, which are located on opposite sides of the belt (40) with respect to a Path (PW) followed by the lateral edge (SW) of the web (W).

Furthermore, preferably, the cutting device (5) comprises a blade (50) mounted on a mobile support (51), the mobile support (51) being in turn mounted on a linear guide (2G) arranged on the structure (2) and controlled by a respective actuator (52).

According to the above example, the structure (2) comprises two uprights (20) joined at the top by a crosspiece (21), and the rectilinear guide (2G) is arranged on the crosspiece (21).

Preferably, the blade (50) is mounted on a rod (5L) controlled by a corresponding pneumatic actuator (55) mounted on the mobile support (51), and the actuator (55) allows the blade to reciprocate relative to the clamping device (1).

Furthermore, preferably, the respective ends of the rod (5L) are hinged to the actuator (55), and the blade (50) is mounted on the other end of the rod (5L).

Also preferably, the assembly formed by the blade (50), the actuator (55) and the lever (5L) is integral with an arm (54) rotatably constrained to the mobile support (51).

It will be appreciated that the above-described system can be used not only for guiding the web out of the unwinder, but more generally it can be used in all cases where it is desired to guide the web by temporarily hooking it to a dragging member that guides it in a predetermined direction. For example, the current guiding system, in which the lateral edges of the paper web are temporarily hooked, can also be inserted downstream of the unwinder, for example upstream of an embosser (not shown in the figures), to avoid possible breakage of the material of the paper web at a point inside the paper converting line.

Indeed, the details of execution may vary in any way in equivalent ways with respect to the various elements described and illustrated, without thereby departing from the concept of solution adopted, and therefore remain within the scope of protection granted to this patent according to the appended claims.

Claims

1. A guiding system for processing a web of paper material, comprising:

-a structure (2) for supporting the clamping device (1);

it is characterized in that the method comprises the steps of,

-the hooking device (4) comprises a flexible member (40) provided with a tip (46) adapted to engage the lateral edge (SW) of the web (W) while the same flexible member (40) moves along a path (P4), the flexible member having a first section (PH) and a second section (PT), the flexible member (40) being mounted on a support (41), the support (41) being movable between a hooking position in which the first section (PH) overlaps the Path (PW) followed by the lateral edge (SW) of the web (W) and a non-operative position in which the first section (PH) is spaced apart from the Path (PW) followed by the lateral edge (SW) of the web (W) and the second section (PT) of the path (P4) is a section along which the web (W) is hooked away from the point thereof.

2. A system according to claim 1, characterized in that it comprises cutting means (5) adapted to cut the web (W) transversely, said cutting means being arranged upstream of the hooking means (4) with respect to the aforesaid advancing direction (WF), said cutting means being constrained to respective movable supports (51), said movable supports (51) moving them transversely to the advancing direction (WF) of the web (W) and being actuated when the hooking means (4) engage the lateral edges (SW) of the web (W).

3. The system of claim 1, wherein the flexible member (40) is a tape and the tip (46) comprises a spike inserted into the tape.

4. A system according to claim 3, wherein the belt is a belt having a rectangular cross section, or a belt having longitudinal grooves, or a belt having a trapezoidal cross section.

5. A system according to claim 3, characterized in that the tips (46) are distributed over the whole length of the belt (40) or over a predetermined portion of the belt (40) so as to provide a segmented hooking surface.

6. The system according to claim 1, characterized in that the hooking device (4) comprises a presser (42) configured to act on the lateral edge (SW) of the web (W).

7. The system according to claim 6, characterized in that the pressing element (42) comprises a brush located on the opposite side of the belt (40) with respect to a Path (PW) followed by the lateral edge (SW) of the web (W).

8. A system according to claim 2, characterized in that the cutting device (5) comprises a blade (50) mounted on a mobile support (51), which mobile support (51) is in turn mounted on a linear guide (2G) arranged on the structure (2) and controlled by a respective actuator (52).

9. The system according to claim 1, characterized in that the structure (2) comprises two uprights (20) joined at the top by a crosspiece (21), and in that the rectilinear guide (2G) is arranged on the crosspiece (21).

10. A system according to claim 8, characterized in that the blade (50) is mounted on a rod (5L) controlled by a corresponding pneumatic actuator (55) mounted on the mobile support (51), and in that the actuator (55) allows the blade to reciprocate relative to the gripping device (1).

11. The system according to claim 10, characterized in that one end of the lever (5L) is hinged on the actuator (55) and the blade (50) is mounted on the other end of the lever (5L).

12. The system according to claims 8-11, characterized in that the assembly formed by the blade (50), the actuator (55) and the lever (5L) is integral with an arm (54) rotatably constrained to the mobile support (51).