REINFORCEMENT INSERT

The present invention relates to an apparatus and method for forming bags having a reinforcement element therein.

The apparatus and the method of the invention are particularly suitable for the production of bags in which the reinforcement element is secured to the bag in a removable manner.

The apparatus and the method of the invention are particularly suitable for producing reinforced bags of the type described, for example, in EP1931572. Such bags are produced from paper, card or other similar materials.

Such bags are obtained by wrapping a sheet so as to form a body of a form which is almost tubular and the longitudinal edges of which are adhesively bonded to each other at a side wall portion in order to form the tubular body which is open at the two longitudinal ends thereof.

The tubular body is folded and adhesively bonded at one of the longitudinal ends in a manner known in the field in order to form the base of the bag being formed. To this end, at this longitudinal end the sheet is suitably shaped.

At the opposite longitudinal end of the tubular body, the walls are not mutually joined but are open so that an opening remains defined for the bag to be formed.

These bags further comprise a reinforcement element which is inserted inside the body and which is intended to reinforce the base thereof.

The bags are initially formed in a flattened configuration with the reinforcement inserted inside the body.

At the time of use, the user opens the bag so as to define the base thereof and positions the reinforcement element so as to position it at least partially on the base of the bag in order to increase the strength thereof and to protect the spots of adhesive which define the base of the bag itself.

The production of such bags in an automated manner is not simple.

In fact, it is necessary to position the reinforcement element inside the bag so that the bag can be readily opened and the reinforcement element can be readily positioned on the base.

In order to achieve this object, the reinforcement element is adhesively bonded to the walls of the bag or secured in a semi-permanent manner thereto.

However, this may lead to damage to the walls of the bag when the reinforcement element is moved in order to be positioned on the base of the bag.

Alternatively, there may be provision for securing the reinforcement element in a permanent manner to the walls of the bag in the final position for use.

There are known, for example, from W02014/070232 apparatuses for the production of reinforced bags in which the support element is adhesively bonded to the bag in a permanent manner during the production of the bag in the final portion of use, that is to say, in the portion of the bag to be reinforced.

A defect of the bags which are obtained with this apparatus is that the spatial requirement thereof in a flattened configuration is high.

This defect is particularly evident when the reinforcement elements are intended to reinforce a base portion of the bag.

In fact, in this zone, the sheet is provided with folds and the edges of the sheet are superimposed and bonded to each other in order to be able to define the base of the bag when the bag is opened and to reinforce the base of the bag.

This increases the spatial requirement of the bags in a flattened configuration. Another defect is that, once the reinforcement is positioned and bonded in the bag, it cannot be moved because it would permanently damage the structure of the bag.

An object of the invention is to provide a method and an apparatus which allow the production of reinforced bags which are provided with a reinforcement element which is positioned inside the bag in a predefined position and which is not permanently secured to the walls of the bag.

An object of the invention is to provide a method and an apparatus which allow the production of reinforced bags in a flattened configuration which are provided with a reinforcement element which is positioned inside the bag in a position different from the position of the reinforcement element in the configuration for use of the bag.

Another object of the invention is to provide a method and an apparatus which allow the production of a reinforced bag with a reinforcement element which is removably and movably secured to the body of the bag.

With the method and the apparatus of the invention, it is possible to produce a bag which is provided with a reinforcement element which is positioned in a predefined position inside the bag without using adhesive or other elements which can secure the reinforcement element to the bag in a permanent or semi-permanent manner.

Furthermore, with the method and the apparatus of the invention, it is possible to produce an unimpaired bag without any tensions particularly in the region of the base of the bag which, during use, is intended to support the weight of the bag.

Therefore, undesirable breakages of the bag are prevented, in particular in the region of the base thereof.

Another object is to provide a bag which is provided with a reinforcement element having a limited spatial requirement in a flattened configuration.

The features and advantages of the invention will be better appreciated from the detailed description of some preferred embodiments which are illustrated by way of non-limiting example with reference to the appended drawings, in which :

- Figure 1 is a schematic side view of an apparatus according to the invention;

- Figures 2 to 4 are a side view, perspective view and plan view of a forming station of the apparatus of Figure 1, respectively;

- Figures 5 and 6 are perspective views broken away by two different angulations of the apparatus of Figure 1 during use;

- Figure 5A is an enlarged view of a detail of Figure 5;

- Figures 7 and 7A are schematic views of a bag which can be obtained according to the invention in a flattened configuration;

- Figure 8 is a schematic view of a bag which can be obtained according to the invention in an erected configuration for use;

- Figure 9 is a schematic view of a strip of tape material which is suitable for obtaining the bag of Figures 7 and 8;

- Figure 10 is a broken-away schematic view of a tubular body which is obtained with the apparatus of the invention. The appended Figures 1 to 6 show an apparatus 100 according to the invention.

The apparatus 100 is particularly suitable for forming bags in a flattened form which are provided with a reinforcement element therein, as in the one shown in Figures 7, 7A and 8.

Figures 7, 7A and 8 show a bag 1 which is produced with the apparatus of the invention in a flattened configuration T and in an erected configuration for use S.

The bag 1 is produced from a tape material, preferably paper, cardboard or biodegradable material.

The bag 1 comprises two front walls 5 which face each other, two side walls 6 which face each other, a base 7 and an opening 8. There is provided inside the bag 1 a reinforcement element 10 which is intended to be positioned, with the bag in the erected configuration for use S, on the base 7 of the bag 1 and sized so as to at least partially cover the base 7 itself.

The bag 1 is obtained from a first tape material M which is cut so as to form a strip 2, which is shown in greater detail in Figure 9 and which is suitably shaped and subsequently folded to produce the bag 1.

The strip 2 is delimited by two opposite longitudinal edges 2A, 2B, which are opposing in the transverse direction XI of the strip 2 and two opposite transverse edges 2C, 2D which are opposing in the longitudinal direction Y1 of the strip 2, and is provided with intended folding lines 3, which are also known as creases and which allow folding of the strip 2 in order to define the bag 1.

In accordance with the number and the configuration of the creases, it is possible to define bags of various forms. The creases 3 comprise a plurality of longitudinal creases 3A, a base crease 3B and an upper crease 3C.

The longitudinal creases 3A define and delimit the front walls 5 and side walls 6 of the bag 1 and allow folding of the strip 2 in order to define the side walls 6 and front walls 5 of the bag.

Each front wall 5 has a width "W" corresponding to the width of the bag to be formed.

The strip 2 may be provided with a variable number of longitudinal creases 3A depending on the number of walls of the bag and/or the form of the side walls 6. In the version shown, there are provided six longitudinal creases 3A in order to define four walls in the bag 1 and to allow folding of the side walls 6 in the manner of a bellows between the front walls 5 with the bag 1 in the flattened configuration T.

The longitudinal creases 3A comprise in particular at least one lateral crease 30 which is capable of defining in each side wall 6 at least two different side wall portions 6A, 6B which can be folded with respect to each other along this lateral crease 30.

This allows folding of the side wall 6 inwards in the manner of a bellows towards the front walls in the flattened configuration T of the bag 1, as can better be seen in Figures 7 and 7A.

The base crease 3B defines the base 7 of the bag 1, that is to say, allows folding of the strip 2 in order to define the base 7 of the bag 1.

The upper crease 3C allows folding of the strip 2 in order to close the opening 8 of the bag 1, if desired.

The upper crease 3C defines on the front walls 5 and side walls 6 closing edges 80 which are intended to be folded and positioned one on the other in order to close the opening 8 of the bag 1.

Preferably, the strip 2 is shaped so that the upper crease 3C defines closing edges 80 on at least two opposing walls of the bag 1, in a particularly preferred version the closing edges 80 are defined on the two front walls 5 of the bag 1.

The upper crease 3B and lower crease 3C are positioned at a distance "D" in the longitudinal direction Y1 of the strip 2 which depends on the dimensions of the bag to be formed.

The longitudinal creases 3A are produced in such a manner that a front wall 5 is positioned in the central band 51 in the strip 2, the two lateral bands 50 of the strip 2 correspond to the side walls 6 and the other front wall 5 of the bag 1.

In order to form the bag 1 in a flattened configuration, there is provision for rotating the lateral bands 50 so as to bring them together and partially overlap them.

Two lateral edges 9A and 9B of the lateral bands 50 are positioned one on the other in a superimposition zone 9 so as to form a body having a virtually tubular form 200 which is shown in Figure 10.

At least at one of the two lateral edges 9A, 9B, there is applied some adhesive so that the edges can be mutually attached in the region of the superimposition zone 9, which can better be seen in Figure 7A. In this manner, a tubular body which is open at the two longitudinal ends is defined.

The tubular body 200 is then folded and adhesively bonded in the region of one of the longitudinal ends, forming base folds 70, so as to close the tubular body 200 in the region of this longitudinal end and to form the folds in order to be able to subsequently form the base 7 of the bag 1. To this end, the corresponding transverse edge 2D is suitably shaped.

The bag 1 is obtained in a flattened configuration T, as shown in Figures 7 and 7A, with the reinforcement element 10 inserted inside the bag 1 itself.

In the flattened configuration T, the reinforcement element 10 is in a production configuration Tl, in which it is supported on one of the front walls 5 of the bag 1 and retained between it and a side wall portion 6A of each of the side walls 6.

Advantageously, as better explained below, the reinforcement element 10 is positioned so as to be interposed between the lower crease 3B and the upper crease 3C of the strip 2.

This makes it easier to open the bag 1 and to form the base 7 thereof.

Furthermore, the reinforcement element 10 in the flattened configuration T is positioned in a zone of the bag which is not involved in the folding of the base 70 so as to reduce the spatial requirement of the bags in a flattened configuration T.

Advantageously, as better explained below, the reinforcement element 10 is positioned so as to be interposed between and retained by a front wall 5 and a side wall portion 6A, 6B.

This improves the positioning of the support element 10 in the bag 1 in the erected configuration of use S, in which the support element 10 is supported on the base 7 of the bag 1.

Figures 1 to 6 show an apparatus 100 constructed according to the invention suitable for producing a bag which is provided with a reinforcement element. The apparatus 100 of the invention comprises a source of a first tape material M and a source of a second tape material N which are intended to form the bag 1 and the reinforcement element 10, respectively.

The first tape material M and the second tape material N are wound on respective reels 101, 102. Reels having various transverse extents can be used in accordance with the dimensions of the bag to be formed and/or the reinforcement element to be used.

The first tape material M is unwound in the longitudinal direction Y2 thereof and has a width LI measured in the transverse direction X2 which is perpendicular to the longitudinal unwinding direction Y2 which is selected on the basis of the dimensions of the bag to be formed.

The second tape material N is unwound in the longitudinal direction Y3 thereof and has a second width L2 measured in the transverse direction X3 which is perpendicular to the longitudinal unwinding direction Y3 which is selected on the basis of the dimensions of the bag to be formed.

The second width L2 of the second tape material N is less than the width LI of the first tape material M so that the reinforcement element 10 can be inserted in the bag 1, as better explained below.

Preferably, the second width L2 of the second tape material N almost corresponds to the width W of the front wall 5 of the bags being formed.

The first tape material M and the second tape material N are preferably selected from a group comprising paper or card, preferably the second tape material N has a thickness greater than the first tape material M.

However, all suitable materials to construct bags and/or reinforcement elements can be used. The apparatus 100 comprises a first unwinding device 103 in order to unwind the first tape material M from the first reel 101 and to advance it through the processing stations which are provided in the apparatus 1 along a processing path P in such a manner that it is subjected to the operations necessary for the formation of a bag 1.

The first tape material M is moved in the advance direction which is indicated by the arrow F in the Figures along the processing path P inside the apparatus 100.

The first unwinding device 103 is configured in such a manner that the first tape material M is moved at an advance speed VA which depends on the productivity of the apparatus 100 and which can be defined during the configuration of the apparatus 100 itself.

The apparatus 100 further comprises a second unwinding device 104 in order to unwind the second tape material N from the second reel 102 and to advance it in the direction of the advance arrow F inside the apparatus 100.

The second unwinding device 104 is configured in such a manner that the second tape material N is moved at a second advance speed VB less than the first advance speed VA, VB<VA.

The ratio between the first advance speed and second advance speed VA/VB depends on the dimensions of the bag 1 to be formed, the dimensions of the base 7 of the bag 1 to be formed and the dimensions of the reinforcement element 10 which it is desired to construct.

The first unwinding device 103 comprises a plurality of pulling devices 105 which are spaced apart along the processing path P and which are arranged to pull the first tape material M and a plurality of advance rollers 106 which are spaced apart along the processing path and on which the first tape material M is conveyed in order to be guided along the processing path P.

The advance rollers 106 may be idle rollers and may be caused to rotate by the pulling devices 105 in order to advance the first tape material M in the direction of the arrow F.

The first unwinding device 103 further comprises redirecting rollers in order to define the desired path for the first tape material M in the apparatus 100.

The apparatus 100 comprises a printing station which is not shown and in which the first tape material M is pulled in order to be printed in order to produce any decorations on the bag being formed.

In a version of the apparatus of the invention, the printing station may not be provided.

The apparatus 100 further comprises a drilling station 12 in which the first tape material M is drilled so as to produce intended breaking points, for example, the intended breaking points 120 shown in Figure 10, in the region of which the first tape material M is subsequently separated so as to define the strips 2 in order to construct the bag 1.

The intended breaking points 120 are capable of defining the transverse edges 2C, 2D of the strip 2, as better explained below.

The drilling devices provided at the drilling station 12, which are not shown in detail in the Figures, are positioned so as to define on the first tape material M a strip 2 having the desired shape which is dependent on the form of the bag to be formed, for example, similar to the one shown in Figure 9.

The drilling devices are controlled so as to intercept the first tape material M at predetermined time intervals which depend on the dimensions of the bag to be formed.

The drilling station 12 is positioned downstream of the printing station 11 if it is provided.

The apparatus 100 further comprises a forming station 14 which is positioned downstream of the drilling station 12 and which is shown in greater detail in Figures 2 to 6, in which the first tape material M is folded in order to form a continuous tubular body 200, as better described below.

Between the drilling station 12 and the forming station 14, the advance rollers 106 are arranged so as to define an advancing path for the first tape material M passing close to a cutting station 13 of the apparatus 100, as better explained below.

The apparatus 100 further comprises a cutting station 13 which is positioned upstream of the forming station 14 and to which the second tape material N is pulled by means of second pulling devices 107 of the second unwinding device 104 and in which the second tape material N is cut into a plurality of sheets 10A, which can better be seen in Figures 5 and 5A, each one being intended to form the support element 10 of the bag 1.

The cutting station 13 is provided with a cutting device 130 which is actuated at predefined time intervals tl which can be adjusted so as to generate sheets 10A and therefore support elements 10 having a desired longitudinal extent

"Dl".

By varying the second advance speed VB and/or the cutting interval tl, it is possible to vary the longitudinal extent Dl of the sheets 10A of the second tape material N and/or the frequency at which they are supplied.

The cutting device 130 is controlled by a timer which is not shown in the Figures and which controls the cutting interval tl.

The cutting interval tl is timed on the basis of the dimensions of the base 7 of the bag 1 to be produced and the longitudinal dimensions of the bag 1 to be produced.

The cutting device 130 is actuated so as to obtain sheets 10A having a longitudinal extent D1 less than or equal to the width D4 of the base 7 of the bag 1, which is preferably approximately 80-99% of the width D4 of the base 7.

There is provided between the cutting station 13 and the forming station 14 a coupling device 20 which is intended to couple the sheets 10A of the second tape material N to the first tape material M, as better described below.

The coupling device 20 is intended to receive the first tape material M which is moved by the unwinding device 103 towards the forming station 14 and the sheets 10A of the second tape material N being discharged from the cutting station 13 and to couple them to each other in order to supply them in the coupled state to the forming station 14.

The coupling device 20 allows the sheets 10A to be coupled to the first tape material M in such a manner that they are positioned in the desired position on the first tape material M, as better explained below, and allows them to be fixed in this position until they are introduced into the forming station 14.

The coupling device 20 is configured to couple the sheets 10A to the first tape material M in a stable but removable manner and without using adhesives or other permanent securing elements.

The coupling device 20 couples the sheets 10A to the first tape material M in such a manner that there is provided a sheet 10A for each of the bags 1 being formed.

The sheets 10A and the first tape material M are supplied to the coupling device 20 in such a manner that the sheets 10A are positioned on the first tape material M in a central position in the transverse direction X2 thereof, that is to say, in the central band 51 of the strip 2.

Advantageously, the sheets 10A are positioned in a position which will not be involved in folding during the forming of the bags so as to facilitate the forming of the bags themselves.

Each sheet 10A is positioned on the first tape material M so as to be arranged between the upper crease 3B and lower crease 3C of each of the bags 1 being formed.

In the coupling device 20, the sheets 10A and the first tape material M are moved at the advance speed VA of the first tape material M.

The coupling device 20 comprises a plurality of coupling rollers 20A which define a path along the coupling device 20 for the first tape material M and for the sheets 10A which is formed so as to allow coupling therebetween.

The coupling device 20 further comprises a guide device 21 for guiding the sheets 10A of the second tape material N along the coupling device 20 in such a manner that the sheets 10A are supported on and coupled to the first tape material M, as better explained below.

The guide device 21 is positioned in such a manner that the sheets 10A are interposed between the guide device 21 and the first tape material M being moved towards the forming station 14.

The guide device 21 allows the sheets 10A of the second tape material N to be guided in order to move the sheets 10A of the second tape material N and the first tape material M together in the advance direction F as far as the forming station 14.

The guide device 21 is positioned so as to keep the sheets 10A of the second tape material N bonded to the first tape material M.

The guide device 21 prevents the sheets 10A from moving with respect to the first tape material M during the advance from the cutting station 13 to the forming station 14.

Therefore, it is ensured that the sheets 10A remain in the predefined position on the first tape material M.

The guide device 21 is intended to guide the sheets 10A of the second tape material N along at least one portion PI of the processing path P which is preferably positioned upstream of the forming station 14 and downstream of the cutting station 13.

The guide device 21 comprises two belts 22, 23 which are provided in positions spaced apart in the transverse direction X2 of the first tape material M and which are intended to interact with the sheets 10A of the second tape material N in order to keep it bonded to the first tape material M.

Each belt 22, 23 is wound between a respective pair of wheels which can be rotated in the direction of the arrow FI in such a manner that the respective belt 22, 23 can slide on the wheels of the respective pair.

The belt is moved by the rotation of the respective pair of rotatable wheels. Each pair of wheels comprises a proximal wheel 24, 25 which is positioned in a proximal position with respect to the forming station 14 and a distal wheel 26, 27 which is positioned in a position further away from the forming station 14 than the proximal wheel 24, 25. Each wheel 24, 25, 26, 27 is advantageously provided on the outer surface thereof with at least one circumferential channel 24A, 25A, 26A, 27A for receiving the respective belt 22, 23.

This allows the connection between the belts and the respective wheels to be kept stable so as to prevent undesirable movements of the belts themselves during the operation of the apparatus 100.

This further allows the ability to use belts having smaller dimensions without any risk of movement thereof.

In some versions which are not shown, there may be provided for each pair of wheels a plurality of belts which are spaced apart in the transverse direction so as to further increase the stability of the sheets 10A on the first tape material M.

This arrangement makes it readily possible to guide sheets 10A having mutually different dimensions with the guide device 21.

In this case, the wheels can be advantageously provided with corresponding channels.

The guide device 21 is further provided with an adjustment device which is not shown in the Figures and which is intended to adjust the transverse distance between the wheels and therefore between the belts.

This allows to adapt the guide device 21 to the dimensions of the sheet 10A and/or the width of the bags to be formed.

Advantageously, the two proximal wheels 24, 25 and the two distal wheels 26, 27 are positioned with mutual spacing corresponding to the width W of the bag to be formed, that is to say, of the central band 51.

In this manner, the lateral bands 50 of the first tape material M are free to be folded with respect to the guide device 21 so as to progressively form the tubular body 200.

The wheels 24, 25, 26, 27 are positioned in such a manner that the belts 22, 23 extend between the cutting station 13 and the forming station 14.

During use, the belts 22, 23 are facing the first tape material M, the sheets 10A being interposed between the belts 22, 23 and the first tape material M. The wheels 24, 25, 26, 27 are actuated in such a manner that the belts 22, 23 slide in a direction in accordance with the advance direction F of the first tape material M and at the same speed as the tape material M so as not to generate relative sliding actions between the sheets 10A and the first tape material M.

In this manner, the belts 22, 23 keep the sheets 10A bonded to the first tape material M in the desired position.

The coupling device 20 further comprises an accompanying device 300 which is interposed between the proximal wheels 24, 25 and the forming station 14 and which is arranged to accompany the sheets 10A of the second tape material N of the forming station 14.

The accompanying device 300 receives the first tape material M and the sheets 10A coupled thereto from the coupling device 20 and accompanies them as far as the forming station 14.

The accompanying device 300 comprises, in the region of each proximal wheel 24, 25, a crescent-like member 32 which is fixed to the rotation pin 31 of the corresponding proximal wheel 24, 25 and a plate 33 which extends between the proximal wheel 24, 25 and the forming station 14.

The plate 33 is preferably metal and has such dimensions as to extend between the crescent-like member 32 and the forming station 14.

In this manner, the sheets 10A of the second tape material N are accompanied by means of the accompanying device 300 by the guide device 21 as far as the forming station 14.

During use, the first tape material M passes around the crescent-like member 32 and the sheets 10A are interposed between the first tape material M and the crescent-like member 32 and between the plate 33 and the first tape material M.

The plate 33 has such dimensions as to extend as far as the opening of the forming station 14 so as to prevent movements of the sheets 10A of the second tape material N before reaching the forming station 14.

The presence of the accompanying device 300 allows the first tape material M and the sheets 10A to be kept coupled as far as the inlet of the forming station 14.

The coupling device 20 is positioned so as to define a portion PI of the processing path P which is inclined with respect to the additional portion P2 of the processing path P which is defined in the forming station 14.

In other words, from the coupling device 20 to the forming station 14, the path of the first tape material M is redirected and this redirection makes it easier to fold the first tape material M in order to form the tubular body 200. Since, as mentioned above, the guide device 21 interacts only with the central band 51 of the first tape material M which is intended to form a front wall 5 of the bag 1, the lateral bands 50 of the first tape material M are free to be folded with respect to the guide device 21.

This promotes the folding of the first tape material M in order to form the tubular body 200.

The apparatus 100 further comprises a gluing device 16 which is intended to apply a desired adhesive to at least one of the two lateral edges 9A and 9B of the first tape material M in order to be able to secure them to each other in the superimposition zone 9.

The gluing device 16 is provided upstream of the forming station 14, advantageously in the region of the coupling device 20.

In this manner, when the two lateral bands 50 are folded towards each other and are superimposed at the superimposition zone 9, they are adhesively bonded to each other and the tubular body 200 is formed.

The forming station 14 comprises a first forming plate 41 and a second forming plate 42, which are shown in greater detail in Figures 2 and 4 and which extend in the advance direction F of the apparatus 1 and on which there is wound the first tape material M in order to form a tubular body.

The first plate 41 and the second plate 42 are, with a horizontal positioning of the apparatus 100, spaced apart from each other along a vertical axis Z and are positioned in such a manner that the first plate 41 is interposed between the second plate 42 and the ground.

The first plate 41 which, with a horizontal positioning of the apparatus 100, is nearer the ground extends substantially parallel with a horizontal axis Y' of the apparatus 100, the second plate 42 is inclined with respect to the horizontal axis Y' in the advance direction F.

In general, the first plate 41 and the second plate 42 are inclined with respect to each other in the advance direction F.

The first plate 41 and the second plate 42 are positioned in such a manner that there is defined therebetween an opening "B" having decreasing dimensions in the advance direction F.

This positioning of the plates 41, 42 makes it easier to form the bag 1, as better explained below.

The angle of inclination between the second plate 42 and the horizontal Y' is selected on the basis of the dimensions of the bag to be formed and in particular of the side walls 6 thereof.

The forming station 14 is provided with adjustment elements which cannot be seen in order to adjust the mutual spacing between the first plate 41 and the second plate 42 and/or to adjust the inclination of the second forming plate 42. In the forming station, the first tape material M is supplied in such a manner that a central band 51 thereof faces the first plate and the sheets 10A of the second tape material N are interposed between the first tape material M and the first plate 41.

This prevents undesirable movements of the sheets 10A.

The first plate 41 and the second plate 42 have a width X4 measured in the transverse direction X2 of the first tape material M which virtually corresponds to the width W of the bag 1 to be formed.

Advantageously, the first plate 41 and the second plate 42 have a width X4 less than the width W of the bag 1 to be formed, preferably approximately 99- 90% of the width "W" of the bag 1 to be formed.

Advantageously, the first plate 41 and the second plate 42 have a width X4 which increases in the advance direction F so that the width X4 of the first plate 41 and the second plate 42 at the outlet of the forming station virtually corresponds to the width W of the bag 1. These arrangements promote the forming of the bag 1.

Furthermore, in a particularly preferred version, the first plate 41 has a concave shape in the transverse direction X with the concavity directed towards the second plate 42.

This further promotes the forming of the tubular body 200, preventing the formation of wrinkles in the first tape material M. This further promotes the adhesion of the sheet 10A to the first plate 41.

Furthermore, this formation prevents the use of pushing elements in order to push the first tape material M towards the first plate 41 and to keep it bonded thereto.

This also prevents any need to stretch the first tape material M in order to make it adhere to the first plate, thereby preventing undesirable tensions in the first tape material M.

The first plate 41 is delimited at the opening of the forming station 14, that is to say, at the end directed towards the coupling device 20, by a rounded edge 41A.

The rounded edge 41A defines the opening of the forming station 14. The rounded edge 41A is advantageously curved towards the coupling device 20 in order to improve the connection between the guide device 21 or the accompanying device 300, when present, and the forming station 14 and to prevent jams of the first tape material M.

The rounded formation of the edge 41A prevents jams of the first tape material M and/or the second tape material N being introduced into the forming station 14.

The plates 33 are positioned so as to be supported on the first plate 41 in order to guide the sheets 10A of the second tape material N on the first plate 41.

The plates 33 are positioned in such a manner that the sheets 10A slide between the plates 33 and are interposed between them and the first tape material M.

In the forming station 14, the sheets 10A are interposed between the first tape material M and a face of the first plate 41 and the relative movement between the sheets 10A and the first tape material M is thereby prevented.

In the version shown, the forming station 14 is further provided with an accompanying device 43 for accompanying the winding of the first tape material M on the plates 41, 42.

Advantageously, the accompanying device 43 comprises at least one pair of accompanying elements which are arranged at opposite sides in the transverse direction X of the forming station 14 and which are intended to engage with the transversely opposed lateral bands 50 of the first tape material M in order to accompany them towards the forming plates 41, 42.

In the version shown, the accompanying elements are provided at the opening of the forming station 14.

Each accompanying element comprises, in the form shown, an arm 44A, 44B which is hinged on a support pin, which is not shown, and which is intended to intercept the first tape material M being discharged from the guide device 21 in order to accompany it towards the plates 41, 42.

In the version shown, there are provided a plurality of pairs of accompanying elements which are spaced apart along the forming station 14 in the advance direction F. In a version which is not shown, the forming station 14 does not have any accompanying device.

Advantageously, the forming station 14 further comprises a folding device 45 in order to fold the edges of the first tape material M on the second plate 42 in order to form the tubular body 200.

Advantageously, the folding device 45 comprises a plurality of pairs of pressing rollers 48, the rollers of each pair of pressing rollers being spaced apart from each other in a transverse direction so as to engage with opposite edges of the first tape material M.

The pairs of rollers 48 are positioned in the advance direction F.

The pressing rollers 48A of the pairs of pressing rollers 48 are intended to intercept the edges of the first tape material M and to fold them on the second plate 42 so as to superimpose the two lateral edges 9A and 9B one on the other in the superimposition zone 9 in order to form a tubular body 200. Since at least one of the two lateral edges 9A and 9B is provided with adhesive, they are mutually attached and there is progressively defined a tubular body 200.

The pressing rollers 48A are further intended to press the lateral edges 9A and 9B in the superimposition zone 9 in order to promote the adhesive bonding of the lateral edges 9A and 9B in order to form the tubular body 200.

The pressing rollers 48A are fixed to an adjustment element in order to adjust the position thereof with respect to the first tape material M and to adjust the pressure which acts thereon.

The position of the pressing rollers 48A of each pair of pressing rollers 48 is adjusted in an independent manner from each other. The forming station 14 further comprises a forming device 46 which is intended to fold the first tape material M in order to define the side walls 6 of the bag 1 being formed. The forming device 46 is intended to fold the first tape material M by inserting it inside the opening "B" between the first plate 41 and the second plate 42.

The forming device 46 comprises at least one pair of forming wheels 47A, 47B which are arranged at opposite sides in a transverse direction X of the forming station 14 and which are intended to interact with transversely opposite portions of the first tape material M in order to insert them in the opening B between the plates 41, 42.

The forming wheels 47A, 47B allow definition of the longitudinal creases 3A of the side walls 6 in order to fold the side walls 6 in the manner of a bellows between the plates 41, 42.

Advantageously, the forming device 46 comprises a plurality of pairs of forming wheels which are spaced apart in the advance direction F.

The forming wheels 47A, 47B are idle wheels on the individual rotation pin and are caused to rotate by being drawn by the contact with the first tape material M.

The wheels of the pairs of wheels 47 are positioned with mutual spacing in the transverse direction which decreases in the advance direction F so as to progressively fold the two side wall portions 6A, 6B at the inner side between the front walls 5.

By forming the longitudinal creases by means of the forming device 46, the sheets 10A of the second tape material N are thus blocked in the region of the central portion W of the first tape material M, being interposed between the front wall 5 and a side wall portion 6A, 6B of each side wall 6.

The folding of the side walls at the inner side between the front walls allows the sheets 10A of the second tape material N to be kept positioned in a stable manner.

The forming station 14 comprises at least one support roller 85, which can be seen in Figure 5A and which is arranged under the first plate 41, that is to say, in such a manner that the first plate 41 is interposed between the support roller 85 and the ground. The support roller 85 is arranged to accompany the first tape material M along the forming station 14, keeping it stretched and bonded to the first plate 41.

At the outlet of the forming station 14, there is obtained a tubular body 200 having a width which corresponds to the width W of the front walls 5 of the bag 1 being formed, with the side walls 6 folded in the manner of a bellows between the two front walls 5 and the sheets 10A of the second tape material N inserted between a front wall 5 and the side wall portions 6A, 6B which are directed towards it.

At the outlet of the forming station 14, the tubular body 200 has the side wall portions 6A, 6B folded in the manner of a bellows towards the inner side and is provided at the inner side thereof, at predefined longitudinal intervals, with sheets 10A of the second tape material N, as better shown in Figure 10.

The formation of the tubular body 200 and in particular the presence of the lateral bellows-like arrangement prevents the undesirable movement of the sheets 10A of the second tape material N.

The second tape material N is in fact kept stable by the bellows-like arrangement of the side walls 6 and compressed between the two front walls 5 of the bag 1 being formed.

In a version which is not shown, in the forming station 14 there is provided a single forming plate. This version is particularly suitable for producing bags with a non-parallelepipedal form, in which the two front walls are connected to each other and the side walls are not provided.

The apparatus 100 further comprises downstream of the forming station 14 a separation station 15 in which the tubular body 200 is separated at intended breaking points 120 so as to generate different tubular portions 201, each one suitable for forming a single bag 1.

The apparatus 100 further comprises a gluing station 17, at which the lower edges of the strip 2 are adhesively bonded and subsequently folded to form the base folds 70.

Downstream of the gluing station 17, there is provided an accumulation zone in which the flattened bags are accumulated in order to be subsequently stored or conveyed to other conversion stations or stored for transport.

In the bags in the flattened configuration T, the sheets 10A are, as mentioned, in a production configuration Tl, in which each sheet 10A is supported on a front wall 5 of the bag being formed and retained in this position by a side wall portion 6A of each side wall 6.

In order to prepare a bag, there is provision for moving away the front walls 5 so as to widen the side walls 6 and to open the base folds 70 in order to form the base 7.

Subsequently, the sheet 10A is rotated, being supported on the base 7, bringing it into the configuration for use SI, in which the sheet is positioned on the base of the bag and acts as a reinforcement element 10 thereof. Therefore, a strong bag which is reinforced is obtained.

The apparatus and the method of the invention achieve the objects set out, allowing a number of advantages to be achieved.

Bags in a flattened configuration having a small spatial requirement are obtained.

Bags in a flattened configuration having a reinforcement element which is positioned in the desired position so as to allow a simple preparation of the bag in an erected configuration are obtained.

The bags obtained do not have internal tensions or breaks as a result of the movement of the reinforcement element 10 in order to be moved from the production configuration, in which it is interposed between the front wall 5 and a side wall portion 6A, 6B, and the configuration for use, in which it is superimposed on the base 7 of the bag 1.