BACKGROUND OF THE INVENTION

The present invention relates to a method and an apparatus for feeding web material for foaming of panels, in particular for simultaneously feeding at least two web materials intended for correspondingly defining external layers of one or more panels obtained by a foaming process, using a polyurethane or phenolic mixture.

PRIOR ART

It is widely known the use of panels having an intermediate layer of insulating material, in particular an intermediate layer of insulating material in expanded polyurethane, and a pair of external coating layers, for example made of paper, and/or of nonwoven fabric of vegetable or artificial fibre or a sheet of plastics often coated with a thin metallic reflective layer or a sheet of sheet metal that is studded, corrugated or provided with another surface profile. Such panels are for example used for thermal and/or acoustic insulation of walls of buildings and room that are thermally conditioned or for conduits of conditioned air. The aforesaid external coating layers have the function of containing the expanding polyurethane foam during the process of obtaining, and the function of constituting the protective external surfaces of the polyurethane foam that, in the absence of such layers, would have a porous and friable surface. Such external coating layers are intended, on one side of the panel, to be exposed towards the external environment, and on the other side of the panel, are intended to come into contact with the walls of the building. For this reason, in most cases, the two coating layers of the panel are different from one another, or have different features/properties because they, each, have to meet specific requirements (e.g. breathability capacity in a direction inside the building, surface affinity that permits good adhesion to the wall, etc).

To produce such panels, the use of plants operating continuously is known that foam a single continuous panel. A plant of this type comprises a pair of horizontal belt conveyors, i.e. a lower conveyor and an upper conveyor, that are spaced apart from one another to bound a foaming area extending horizontally along the advancement direction. The intermediate layer of the panel is obtained with a foaming process that provides dispensing a reactive polyurethane mixture that is suitable for forming the foam in the aforesaid foaming area defined between the two conveyors.

The two aforesaid external coating layers of the panel are obtained by unwinding respectively a first lower web material from a first reel, and a second upper web material from a second reel. Two distinct reels are thus provided each of which provides a single respective web material intended to generate a single corresponding coating layer of the panel.

For each web material, intended to generate a respective external coating layer of the panel, a dedicated device is thus provided for supporting and unwinding a single reel. With the reel in use a stand-by reel is associated that replaces the reel in use when the latter is almost finished in order to obtain continuity from the foaming process to avoid undesired machine downtime. Further, for each distinct web material, a cutting and joining device is provided, that cuts the tail ends of the web getting exhausted and the head ends of the new web, to head and join said two ends.

The upper and lower belt conveyors guide, by contrasting the thrust of the foam, and maintain in position the respective layers of web material intended to form the external surfaces of the panels. Such two layers of web material, thus, in the foaming area, respectively define an upper surface and a lower surface facing one another.

The first and the second continuous web material, resting on the respective upper and lower surfaces of the two belt conveyors, are advanced together with the latter along the advancement direction. A dispensing distributor dispenses on the first, lower, web material, a layer of polyurethane or phenolic mixture that progressively expands freely until the resulting polyurethane or phenolic foam comes into contact with and adheres to the second upper web material that moves parallel with and at the same speed of the first web material that is below and spaced apart, so as to obtain progressively a single continuous semifinished product. The expanding polyurethane or phenolic mixture is laterally contained by folding upwards the two opposite edges of the first continuous web material made of paper or plastics or another flexible material; the aforesaid two opposite edges are held in position folded upwards by suitable side elements fixed to the tiles or by means of webs of plastics unwound from side lateral reels and kept in shape by side belts or chains.

As disclosed above, for each coating layer of the panel is provided the use of a corresponding reel of web material with which a further stand-by reel is associated, of a respective supporting and unwinding device and of the respective cutting and joining device. It is necessary to ensure that the feeding of two web materials occurs in a mutually synchronised manner and at the same speed so that the panel is obtained in a suitable manner. The configuration disclosed above thus entails structural and functional complexity and overall dimensions that increase significantly in proportion to the number of layers of web material that it is necessary to process.

It is obvious that if it were desired to proceed with foaming two or more panels simultaneously, the aforesaid overall dimensions and the necessary current splicing operations of the webs would entail critical issues and problems that would be difficult, if not impossible, to address.

It would therefore be desirable to have a system for feeding the layers of web material that was structurally and functionally simplified, highly versatile, and that enabled the required overall dimensions to be minimised.

OBJECTS OF THE INVENTION One object of the present invention is to improve the methods and apparatuses for feeding web materials intended for generating coating layers on foamed insulating panels. Another object is to provide a simple and versatile solution for feeding layers of web material that is able to minimise the overall dimensions associated with the plants for continuous foaming of single or multiple panels. A further object of the present invention is to provide a method and an apparatus that enable a plurality of web materials to be fed, so as to make it possible to obtain simultaneously several parallel-foamed panels with minimised overall dimensions, and at the same time ensure high levels of reliability and precision in the operations of unwinding, joining and feeding web materials.

In particular, a further object of the present invention is to provide a method and an apparatus for feeding several layers of web material to an apparatus for simultaneous foaming of two or more panels, object of Italian patent application MI2013A000316 and of Italian patent application MI2013A000866, filed respectively on 04 March 2013 and on 28 May 2013 both in the name of this same applicant.

SHORT DESCRIPTION OF THE INVENTION

This and other objects and advantages of the invention are achievable by a method according to what is defined in claim 1 and by an apparatus according to what is defined in claim 10.

In a first aspect of the invention a method is provided for feeding web material for foaming of panels comprising the steps of:

i. simultaneously unwinding a plurality of web materials from reel means that comprise one or more multiple reels, on each multiple reel there being wound a plurality of distinct superimposed web materials arranged for generating respective external coating layers for one or more panels;

ii. simultaneously advancing said web materials at a controlled speed along an advancement path and according to respective mutually parallel planes through a foaming region in which said one or more continuous panels are obtained progressively;

iii. accumulating, for each finishing multiple reel, respective accumulation portions of the web materials in an accumulating station placed upstream of said foaming region with respect to said advancement path;

iv. grasping and holding in a joining operating region and in positions spaced apart from one another the tail-end flaps of said accumulation portions of web material and separating and simultaneously trimming said end flaps from the corresponding finishing multiple reel so as to generate tail ends ready for a subsequent splicing operation,

v. cutting the initial flaps of the web materials of a stand-by multiple reel to replace the finishing reel and trimming said initial flaps so as to obtain head ends that are ready to be joined to the respective tail ends;

vi. bringing the tail ends near and superimposing the tail ends on the respective head ends in reciprocally stationary position to simultaneously join the accumulation portions to the respective web materials of said stand-by multiple reel. In a second aspect of the invention an apparatus is provided for feeding web material for foaming of panels comprising:

- supporting and unwinding means for one or more multiple reels, each multiple reel comprising a plurality of distinct web materials wound and superimposed on one another and arranged for generating respective external coating layers for one or more panels;

- dragging- stretching means configured for simultaneously stretching and dragging at a controlled speed the web materials along an advancement path and according to respective mutually parallel planes inside a foaming region in which said one or more panels are progressively and continuously obtained;

- accumulating means arranged for accumulating, for each finishing multiple reel, respective accumulation portions of the respective web materials in an accumulating station placed upstream of said foaming region with respect to said advancement path;

- holding means and cutting means configured for grasping and simultaneously holding the tail-end flaps of said accumulation portions in positions spaced apart from one another and configured for separating from the corresponding finishing multiple reel and simultaneously trimming said end flaps to generate tail ends that are ready for a splicing operation, said means being further configured for grasping and simultaneously holding in spaced positions the web materials of a stand-by multiple reel to replace said finishing reel and to trim the initial flaps thereof to obtain head ends ready to be joined to the respective tail ends;

- joining means configured for transversely applying gluing materials or webs on the head ends and/or on the tail ends to be joined, or for activating biadhesive strips on said head ends and/or on said tail ends for each web material, said joining means being further configured for bringing the tail ends near the respective head ends and superimposing with pressure on, and joining the tail ends to the respective head ends so as to obtain a multiple junction and simultaneously connect said accumulation portions to the respective web materials of said stand-by multiple reel.

The method and the apparatus according to the invention enable the aforesaid objects to be achieved. In particular, owing to the use of reels on each of which several layers of web material are wound, and owing to the possibility of making a simultaneous multiple junction between the finishing webs and the new webs, managing several web materials is facilitated, ensuring continuity for the panel-foaming process, and above all significant reduction in the overall dimensions is achieved associated with a significant structural simplification in the plant, eliminating the redundancy of one or more devices. Owing to the capacity to generate a multiple junction of the webs, undesired slow-downs or temporary plant stops are avoided, and also the risk of possible web jams. Further features and advantages will be clear from the appended claims, from the figures and from the description that follows.

SHORT DESCRIPTION OF THE DRAWINGS

The invention can be better understood and implemented with reference to the attached drawings, which illustrate some embodiments thereof by way of non- limiting example, in which:

Figure 1 shows schematically a first embodiment of an apparatus for feeding web material according to the invention;

Figure 2 is a top view of the apparatus in Figure 1 ;

Figures 3 and 4 show schematically respectively a device for stopping the webs by a vacuum and a presser device for stopping the webs, which are included in the apparatus according to the invention;

Figure 5 shows schematically a device for the multiple simultaneous cutting of the tail ends of the web materials of the reel that is getting exhausted and for the multiple simultaneous cutting of the head ends of the web materials unwound from a new multiple reel;

Figure 6 shows schematically an adhesive dispensing device for the ends of the web materials;

Figure 7 shows schematically a second embodiment of an apparatus for feeding web material according to the invention;

Figure 8 is a top view of the apparatus in Figure 7;

Figures 9 and 10 show schematically respectively a third and a fourth embodiment of an apparatus for feeding web material according to the invention in which multilayered reels are visible that are arranged according to respective vertical axes;

Figures 11 to 14 show schematically various operating steps of an apparatus according to the invention.

DETAILED DESCRIPTION OF THE INVENTION With reference to the attached Figures, some embodiments are shown of an apparatus 1 for feeding web material for foaming of insulating panels. In particular, the apparatus 1 according to the invention disclosed below is combinable with, i.e. can be used to feed, an apparatus for simultaneously foaming two or more panels, object of Italian patent application MI2013A000316 and of Italian patent application MI2013A000866, filed in the name of this same applicant.

In the following description reference is made to panels of composite type, i.e. comprising pairs of external layers of web material between which intermediate layers of expanded polyurethane or phenolic material are interposed.

The external coating layers are obtained from web materials that can comprise paper, plastics, nonwoven fabric of vegetable or artificial fibre, plastics coated with a thin reflective metal deposit, or any other type of flexible material or smooth, studded or ribbed sheet metal with thicknesses less than 1 mm.

With reference to Figure 1, the apparatus 1 extends according to an advancement path for the web materials that starts from a housing positioning zone for the reels and traverses in succession a joining station 20 and an accumulating station 8 included in the apparatus 1.

The accumulating station 8 is used to accumulate a certain quantity of web materials 4 to ensure continuity of feeding of the foaming apparatus during the multiple splicing operations of the web materials, in which the finished reels are replaced by new reels. The accumulating station, in one embodiment, better disclosed and shown in the figures, is of the type comprising roller devices that are suitably arranged and are movable towards one another to impose on the web materials 4 accumulating paths made with a series of multiple curves so as to define accumulation loops that are spaced apart from and are slidable in relation to one another. This enables a multiple junction to be made further upstream in stationary conditions, in which the web material parts affected by the splicing operation remain temporarily stationary without moving in the advancement direction for all the time required for suitable junction-cutting means to complete the junction. Continuity of feeding is assured by the web portions accumulated in a loop that progressively move from the spaced curve configuration to an extended almost rectilinear configuration, as disclosed better further on.

In another possible embodiment (not shown), the junction-cutting means is movable in the advancement direction of the web materials 4, in other words it is able to follow the latter by performing - in a movement that is synchronous with the advancement speeds of the webs - the cutting, trimming and splicing operations. In this embodiment, it is necessary to have available a free manoeuvring zone along which the cutting-joining means can move longitudinally in a reciprocating manner, i.e. move forward in one direction and return backward in the opposite direction. In this case, the accumulating station does not need return roller devices as in the previous case, but is simply represented by a space that extends in the longitudinal advancement direction and accommodates rectilinear extended portions of web material intended to act as accumulation portions. In this case, the zones of the web materials 4 intended to undergo the splicing operation move like all the rest of the sheet material. The cutting-joining means hook and prepare by trimming the head ends of the new reel, and grasp and prepare, by trimming, the tail-end-flaps of the finishing reel by which they are dragged during these operations. Continuity of feeding, and thus continuity of process, is assured by the free portions of sheet material that are gradually used up whilst the cutting-joining means follow advancing integrally with the web materials during the multiple splicing operation. In the example in Figure 1, the apparatus 1 comprises supporting and unwinding means 2 that support a pair of multiple reels, in particular a first multiple reel 3A and a second multiple reel 3B.

The first multiple reel 3A, in the schematised drawings, shows the reel currently in use, whereas the second multiple reel 3B acts as a stand-by multiple reel, i.e. it is used to replace the first multiple reel 3A once the latter finishes without causing any interruption to the panel-foaming process as disclosed below.

The multiple reels 3A, 3B can be prepared beforehand, with suitable off-line winders, superimposing and winding several distinct web materials on the same cylindrical core.

In the example in Figure 1 a multiple reel is used that comprises four web materials 4. The web materials wound on the same multiple reel can all be of the same type, so as to coat each panel with the same type of material on both faces for example with layers of paper.

The web materials wound on the same multiple reel can also comprise materials of different type, so as to coat a face of each panel with a first type of web material, and the opposite face with a different sheet material.

In the example in Figure 1, in a non-limiting manner, reference is made to feeding four web materials, which for the sake of simplicity can be considered to comprise four paper webs to coat simultaneously and continuously two distinct panels. It is nonetheless possible to configure the apparatus 1 for processing larger numbers of web materials, which can be of the same type of material or of different types from one another, to make more than two panels simultaneously and continuously, thus using multiple reels with a different number of web materials, according to specific use requirements, and possibly also one or more single reels.

The supporting and unwinding means 2 which are included in the feeding apparatus 1 support the first reel 3A and the second reel 3B according to respective mutually parallel axes arranged parallel to the advancement planes of the web materials 4.

The supporting and unwinding means 2 which are included in the feeding apparatus 1 can be made according to two possible configurations. According to a first configuration, shown in Figure 1, the supporting and unwinding means 2 are configured for supporting the first reel 3A and the second reel 3B in a stationary position.

In a second configuration, shown in Figure 7, the supporting and unwinding means 2 are of the tiltable type, i.e. rotatable by 180° around a hinging axis 19. The supporting and unwinding means 2 can rotate from a first position in which the first reel 3A is in an advanced position, i.e. nearer an operating region 11 in which the joining station 20 is provided whereas the second reel 3B is in a retracted position, i.e. farther from the joining station 20, to a second position in which the positions of the two multiple reels 3A and 3B are switched, this occurring because the first multiple reel 3A is already finished.

The supporting and unwinding means 2 comprise an axial supporting spindle for each reel. With the supporting spindles expansion or opposite cone stopping devices are coupled that are driven to stop the cylindrical core of the reel on which the web materials 4 are wound.

The supporting spindles are motorized to obtain a web unwinding movement and are operationally connected in a correlated manner to dragging-stretching means 5 which are included in the apparatus 1 that are configured for simultaneously stretching and dragging at a controlled speed the web materials 4 along the advancement path. The dragging-stretching means 5 are provided with a clutch or brake that, sliding, enables the distinct web materials 4, for example made of paper, to be pulled and dragged by the foaming apparatus located further downstream, permitting fine adjustment and synchronisation of the feed and advancement speed. The spindles are removable from the respective supporting and unwinding means 2 to be able to be inserted into the core or heart of the new reel and thus be again placed on the line, in the apparatus 1.

The spindles have shaped supporting portions by means of which they can be hooked and easily raised for example by cranes or forklift trucks.

The web materials, unwound from the respective multiple reel, are supported and separated from one another by suitable separators 17 that can comprise separating planes on which slide the web materials, or a series of motorized rollers or belts or a series of idle or free rollers.

The initial ends of the webs of the new reel can be inserted into the aforesaid separators automatically or manually, whilst another reel is being wound continuously, thus avoiding having to interrupt the panel production process.

Further downstream a sliding section for the web materials is provided in which is located the joining station 20 (which will be disclosed better below) and which, similarly to the preceding separating section, comprises sliding planes on which the web materials slide, or a series of motorized rollers or belts or a series of idle or free rollers, and stopping or holding means 10 operationally associated with multiple cutting means 12.

The apparatus 1 comprises, in the joining station 20, holding means 10 and cutting means 12. The holding means 10 are configured for grasping, or hooking or pinching, and simultaneously holding some portions of the web materials 4 of the first reel 3A in a stationary position, or anyway in a relatively stationary position with respect to the initial flaps of the web materials of the second stand-by reel 3B. The cutting means 12 are configured for separating such web materials from the corresponding multiple reel 3 A once it is finished so as to generate trimmed tail ends 13 ready for joining.

The holding means 10 and the cutting means 12 are further configured for grasping, or hooking or pinching, and simultaneously holding in a stationary position, (or relatively stationary with respect to the end-flaps of the web materials of the first reel 3A) and cutting the web materials 4 of the new multiple stand-by reel 3B to obtain corresponding trimmed head ends 14 to be coupled with the respective aforesaid tail ends 13.

The cutting means 12 are configured for cutting simultaneously the four, or other number, web materials from the reel 3A in use when it is already finished, thus separating such web materials 4 from the respective tail end connected to the reel core. The corresponding tail ends 13 are thus generated that are suitably trimmed to be joined to the new web materials of the stand-by reel 3B.

Similarly, the cutting means 12 act to cut and simultaneously trim the web materials 4 of the new multiple reel 3B. The head ends 14 and the respective tail ends 13 are subsequently joined together by joining means 15 disclosed below.

A possible form of implementation of the cutting means 12 is disclosed below in a non-limiting manner.

The holding means 10 comprise a plurality of holding units for the web materials of the first reel 3A and as many holding units for the web materials of the second reel

3B.

The holding units 10 are arranged spatially in succession according to the advancement path and also separated, or spaced, both longitudinally and transversely to the advancement path. With this configuration, the tail ends 13 are stopped in respective zones zl, z2, z3, z4, which are arranged spatially in succession, one after another, along the advancement path and are separated from one another transversely to the advancement path. Similarly, the head ends 14 are stopped in respective zones ζ , ζ2' , ζ3', ζ4' , that are arranged spatially in succession, one after another, along the advancement path and separated, or spaced, in respect to one another in a direction that is transverse to the advancement path, as shown better in Figure 3. Owing to this configuration, each head end 14 faces the homologous tail end 13 and is thus ready to be joined to the latter.

In one embodiment, shown in Figure 3, the holding means 10 is of the air sucking type, i.e. configured to generate a certain degree of vacuum on the surface and to exploit this vacuum to hold and stop the head ends 14 and tail ends 13. In particular the holding means 10 can include a sucking fan, or another equivalent suitable means for generating and maintaining a depression inside the conduits connected to the surface of suitable drilled resting and holding plates for the respective web materials 4.

In a second possible embodiment, the holding means 10 comprise a movable presser device that includes clamping plates and flat pressing laminas 23, configured as a gripper, fork or tine. Between the two laminas or clamping plates of each pair a respective web material 4 is inserted transversely.

As shown in Figure 3, the four layers of web material are stopped in spaced positions along the feed direction.

The pressing laminas are configured suitably for being able to slide and be extracted transversely during a subsequent splicing operation. For this purpose, the clamping plates can be coated with a non-stick or low friction coefficient material, whereas the clamping laminas can be coated in elastic material with good friction such as rubber. Alternatively, pressing planes can be provided that are coated with a web that slides in a direction that is transverse to the advancement path of the web materials 4. Suitable projecting ridges on the clamping plates enable the head ends to be pressed against the respective tail ends on the lower laminas.

The cutting means 12, in particular can comprise a series of cutting blades 12A for the web materials 4 of the finishing reel 3A and a further series of cutting blades 12B for the web materials 4 of the new waiting reel 3B. For each section of the web separator, a slot can be provided that is arranged transversely to the advancement direction, in which a respective cutting blade of the web material slides.

The cutting means 12 comprises a movable frame on which the blades are mounted which can be of the knife type or of the rotating circular type. The frame can translate to insert and extract transversely the cutting blades for both the upper and the lower web materials.

It is possible to provide a single common supporting frame both for the blades 12A and for the further blades 12B, or two distinct, upper and lower, supporting frames can be provided respectively for the blades 12A and for the further blades 12B.

The cuts that are made on the web materials of the finishing reel 3A have to be spaced apart of one step along the feed direction, with respect to the cuts of the homologous web materials of the new reel 3B.

To ensure correct staggering of the cuts, the possible single frame is movable, not only orthogonally, but also longitudinally to the feed direction of the sheets.

A suitable collecting grid provides to the collection of the scraps generated and dropped by the cutting means 12.

The apparatus 1 comprises joining means 15 configured for bringing the tail ends 13 near the respective head ends 14 and superimposing with pressure on, and joining the tail ends 13 to the respective head ends 14 so as to obtain a multiple junction and simultaneously connect the web materials 4 of the finishing reel 3A to the homologous web materials 4 of the new stand-by reel 3B.

The joining means 15 comprises applicating means, or spreading or distribution units 16 configured for applying a substance or a biadhesive strip to each tail end 13 and/or to the respective head end 14.

In particular, the joining means 15 includes a supporting structure that supports many spreading units to spread an adhesive substance or apply a biadhesive strip to the number of layers of paper to be joined. The aforesaid supporting structure moves transversely to the feed direction to insert itself between the web materials and subsequently lower itself to the ends of the lower sheet materials. Subsequently, the supporting structure moves again in a transverse direction this time in an opposite direction so as to spread the adhesive substance between the fork pressing laminas whilst it progressively disengages from the web materials.

Alternatively, the joining means comprise activating means for activating an adhesive substance already previously present on the tail ends 13 and/or on the head ends 14.

In another embodiment, the joining means 15 comprise electromagnetic induction welding means, configured for performing electrically induced welding by heating locally the interfaced joining zones. The web materials 4, in this case, will be suitable to be welded by electroinduction, providing for example suitable materials, or substances or surface treatments. The welding means act once that each head end 14 is in contact with the respective tail ends 13.

The joining means 15 further comprise presser- actuator means 18 configured for bringing the tail ends 13 near the respective head ends 14 and superimposing on, and pushing one against the other each tail ends 13 to the respective head ends 14, simultaneously for all the web materials 4.

It is possible to configure the apparatus in such a manner that the presser- actuator means 18 operate to lift the ends of the webs located in a lower position to the ends of the homologous webs located at a higher position. In an equivalent manner, it is possible to configure the apparatus in such a manner that the presser- actuator means 18 are driven to lower the ends of the webs located in a higher position to bring the webs to and join the webs to the ends of the corresponding webs located in a lower position.

To ensure continuity to the panel foaming process especially during the steps of replacing the reel and joining the web materials, the aforesaid accumulating station 8 located upstream of the foaming station 9 and downstream of the joining station 20, is provided that acts as an accumulation unit for the web materials 4.

Thus in the accumulating station 8, for each multiple reel 3A that is now getting exhausted, respective accumulating portions 7 of the web materials 4 are accumulated that are gradually fed to the foaming station whereas further upstream the operations of webs joining in stationary conditions are performed, i.e. in the absence of a movement of the webs in the advancement direction.

The accumulating station 8 consists of movable multiple rollers 22. The layers of paper, which are still separated from one another leaving the joining station 20, are joined again and accumulated on the various rollers arranged along a path, of "zigzag" type, that varies in direction.

The movable lower rollers create the loops necessary for compensating consumption and are pulled according to approach paths approximately upwards as the accumulation portions 7 are consumed.

The action of tensioning the web materials is ensured by the weight of the lower rollers 22 that can be helped and assisted by suitable pneumatic pistons. In addition to the aforesaid holding means 10, a further safety stop 21 is provided for the webs, which is placed at the entry to the accumulating station 8.

Upon exiting the accumulating station 8, the various layers of web material 4 are again separated and addressed to the multiple foaming apparatus located downstream.

In a possible version that is not shown, in the feeding apparatus 1 further devices can be provided for unwinding strips of paper or another flexible material, intended for being applied to the narrow side faces of the panels, and the very least to the narrow lower faces in the case of panels foamed according to vertical planes.

In one embodiment, downstream of the accumulating station, a web is unwound, from a reel with a single web material. The web is then cut longitudinally into two or more strips, the edges of which are folded upwards. Such strips with folded edges, are progressively inserted on the bottom of each panel being foamed.

In the case of a foaming apparatus with horizontal planes, the edges of the lower paper are folded upwards.

The operation of the apparatus 1 in the embodiments of Figures 1 and 7 is now disclosed with references being made also to Figures 11 to 14.

The web materials 4 of a new reel are unwound by driving the respective motor of the spindle and separated from one another. The respective front ends are inserted into the roller separators and positioned in the joining station 20 to be trimmed suitably so as to be ready to be joined to the tails of the webs getting exhausted.

The holding means 10 of the vacuum type and of the pressing laminas type act to maintain in a stationary position the aforesaid web ends, as shown in Figures 11 and

12. When the reel 3A currently in use is getting exhausted, the respective end flaps of the webs 4 are also stopped by the holding means 10 and are then cut and trimmed by the respective cutting means 12. In the meantime feeding the paper webs to the foaming apparatus is assured by the accumulating station 8 located downstream of the holding, cutting and joining station 20.

In the meantime, in the station 20, the cutting means 12 by inserting themselves transversely to the feed direction, cut and trim the head ends 14 of the new web materials 4.

In the transverse return movement, in the opposite direction to the movement that has just been made, the cutting means 12 also cut and trim the tail ends 14 of the web materials 4 of the now consumed reel.

These steps are schematised in Figures 12 and 13.

The scrap portions of the heads and tails fall on suitable forks and are simultaneously evacuated and conveyed outside the apparatus 1.

As shown before in Figure 13 and subsequently in Figure 14, the applicating means 16 spread the adhesive substance on the head ends 14 of the lower webs 4 and subsequently the presser- actuator means 18 advance upwards to press each head end 14 against the respective tail ends 13. When the presser- actuator means 18 are lowered again, the vacuum generation of the holding means 10 is interrupted or the respective pressing laminas are removed from the webs 4.

In a further possible embodiment, the presser-actuator means are activated to press each tail end with the corresponding head end and subsequently welding heads make the junction by means of a weld bead or electric induction melting.

For the apparatus embodiment in Figure 1, the tilting supporting and unwinding means 2 rotate by 180° around the axis 19 to transfer the new reel 3B forwards. At this point the roller or sliding plane separators are again set up for the insertion of new web materials of a new stand-by reel.

As already mentioned, it is possible to configure the apparatus 1 so as to process a different number of layers from what has just been disclosed, or several types of web materials simultaneously, using for example also single reels in addition to the multiple reels.

For example, in another two possible embodiments shown respectively in Figures 9 and 10, the apparatus 1 is configured for feeding webs to a foaming apparatus provided with vertical belt conveyors 40. In other words, the apparatus 1 feeds web materials along vertical planes, along a horizontal feed direction, so as to enable two panels that are mutually parallel and lie on vertical planes to be foamed simultaneously. In this the supporting and unwinding means 2 are configured for supporting a first multiple reel and a second stand-by multiple reel, each having two wound web materials.

The web materials 4, unwound from the first multiple reel, each generate a first coating layer 30 on the respective panel. The first two coating layers are thus placed further inside with respect to the belt conveyors 40 of the apparatus 1.

Moreover further supporting and unwinding means are provided for supporting, on opposite sides, two single reels 3S, i.e. each having one web material 4S which can be of a different nature respect to the material of the multiple reels 3 A and 3B. With each single reel a further single stand-by reel 3SR is associated that replaces the reel currently in use, once the latter finishes.

In this case, each web material 4s generates a second coating layer 31 on the respective panel. In these embodiments, separate holding, cutting and joining devices are provided for each web material unwound from a multiple reel 3 A and for each web material 4s of the single reels 3S.

As disclosed above, in the feeding apparatus embodiments 1 previously disclosed with reference for example to Figures 1 and 7, the reels are arranged with their own horizontal axes and the webs exiting the accumulating station 8 adopt horizontal lying planes.

Nevertheless it should be emphasised that the aforesaid apparatuses 1 can also, with the necessary precautions and modifications, be used to feed the apparatus for vertical foaming panels. It is thus possible to rotate all the devices disclosed above by 90° so that they adopt a vertical arrangement, for example by orienting the rotation axes of the supporting and unwinding means vertically, and similarly for the other components of the apparatus 1.

Otherwise, it is possible to maintain the apparatus configuration unaltered, as disclosed for the embodiments of Figures 1 and 7, providing however, at the exit from the accumulating station 8, suitable rollers oriented at 45 degrees that deflect the web materials until the web materials are made to adopt respective vertical lying planes that are mutually separate and parallel.

As can be deduced from what has been disclosed, the apparatus 1 and the respective method enable the objects declared above to be reached. In particular, great versatility of use of the apparatus 1 is obtained which enables, in an extremely flexible manner, a plurality of web materials to be fed simultaneously and without interruptions to foam one or more continuous panels, enabling the management of the web materials to be simplified significantly and the associated overall dimensions to be reduced significantly. Owing to the ability to generate a multiple junction of the webs, undesired slow-downs or temporary plant stops are avoided, and also the risk of possible web jams.

It is possible to configure and dimension the apparatus 1 in the desired manner according to specific needs and variations on and/or additions to what has been disclosed and illustrated above in the attached drawings are possible.