WO2022123479A1

WO2022123479A1 - Apparatus and process for packaging a product in a pouch

Info

Publication number: WO2022123479A1
Application number: PCT/IB2021/061497
Authority: WO
Inventors: Umberto Zanetti; Silvio Quaglia; Andrea Biondi; Paolo Guareschi
Original assignee: G.D S.P.A.
Priority date: 2020-12-11
Filing date: 2021-12-09
Publication date: 2022-06-16
Also published as: EP4259528A1

Abstract

An apparatus (1) for packaging a product in a pouch is described, said apparatus comprising at least one unit (10) for feeding a band (100) of wrapping sheet unwound from a reel, so as to feed the band (100) along an advancement path (K); a unit (20) for folding the band (100), for folding the band about a folding line (100I) oriented parallel to the advancement path (K) so as to superimpose two band portions (100A, 100B) on one another; or a coupling unit (30) for joining to the band (100) a further band (100') of another wrapping sheet obtaining a band (101) with the two wrapping sheets joined together along a direction oriented parallel to the advancement path (K) and superimposed together at least partially, the two wrapping sheets forming two band portions (100A, 100B) superimposed on one another; a welding unit (40) for forming in succession sealing lines (100II), which are transverse to the advancement path (K) and which fix together the two superimposed band portions (100A, 100B) and define, preferably by a continuous movement, a succession of pouches (110) connected to one another along the transverse sealing lines (100II); a cutting unit (60) for dividing the band into the single pouches (110) along the transverse sealing lines (110II); a filling unit (70) for dispensing a product into the single pouches (110); a further welding unit (80) for closing the single filled pouches. The apparatus has the particular feature that the welding unit (40) comprises a first series and a second series of welding members (42, 43) which are arranged opposite each other.

Description

Apparatus and process for packaging a product in a pouch

****

TEXT OF THE DESCRIPTION

The present invention relates to an apparatus for packaging a product in a pouch, comprising:

- at least one unit for feeding a band of wrapping sheet unwound from a reel, for feeding the band along an advancement path;

- a unit for folding the band, for folding the band about a folding line oriented parallel to the advancement path so as to superimpose two band portions on one another, or a coupling unit for joining to the band a further band of another wrapping sheet so as to obtain a band with the two wrapping sheets joined together along a direction oriented parallel to the advancement path and superimposed together at least partially, the two wrapping sheets forming two band portions superimposed on one another;

- a welding unit for forming in succession sealing lines which are transverse to the folding line or the longitudinal sealing line and which fix together the two superimposed band portions and define, preferably by a continuous movement, a succession of pouches connected to one another along the transverse sealing lines;

- a cutting unit for dividing the band into the single pouches along the transverse sealing lines;

- a filling unit for dispensing a product into the single pouches;

- a further welding unit for closing the single filled pouches; wherein the welding unit comprises a drum which is rotatable, preferably with a continuous movement, about a rotation axis and which carries, on a peripheral region thereof along which the band advancement path extends, a series of welding members which are distributed around the rotation axis and face outwardly with respect to the drum for forming the transverse sealing lines on the band lying along a theoretical surface parallel to the rotation axis of the drum.

An apparatus of the type indicated above is for example described in the document US 3505776.

The object of the present invention is to provide an improved solution compared to the prior art, m particular as regards at least one of the following aspects:

- better production quality;

- greater productivity;

5 - greater versatility;

- greater reliability.

The object mentioned is achieved by means of an apparatus for packaging a product in a pouch, having the characteristic features forming the subject of Claim 1 and the following claims.

In particular, the apparatus for packaging a product in a pouch preferably comprises at least one of the following characteristics:

The apparatus comprises preferably at least one unit for feeding a band of wrapping sheet unwound from a reel, for feeding the band along an advancement path. 5 The apparatus comprises preferably at least one band folding unit, for folding the band about a folding line oriented parallel to the advancement path so as to superimpose two band portions on one another.

The apparatus comprises preferably at least, as an alternative to the folding unit, a coupling unit for joining to the band a further band of0 another wrapping sheet so as to obtain a band with the two wrapping sheets joined together along a direction oriented parallel to the advancement path and superimposed together at least partially, the two wrapping sheets forming two band portions superimposed on one another.

The apparatus comprises preferably at least one welding unit for5 forming in succession sealing lines which are transverse to the advancement path and which fix together the two superimposed band portions and define, preferably by a continuous movement, a succession of pouches connected to one another along the transverse sealing lines.

The apparatus comprises preferably at least one cutting unit for dividing the band into the single pouches along the transverse sealing lines.

The apparatus comprises preferably at least one filling unit for dispensing a product into the single pouches.

The apparatus comprises preferably at least one further welding unit for closing the single filled pouches. 5 The apparatus preferably has the said welding unit which comprises a drum which is rotatable, preferably with a continuous movement, about a rotation axis, and which carries, on a peripheral region thereof along which the band advancement path extends, a series of welding members which are distributed around the rotation axis and face outwardly with respect to the

5 drum for forming the transverse sealing lines on the band lying along a theoretical surface parallel to the rotation axis of the drum.

The apparatus is preferably such that the welding unit comprises a second series of welding members distributed around the rotation axis of the drum in positions corresponding to the members of the first series and arranged, in an operative position, opposite the welding members of the first series so as to press the band against the welding members of the first series.

The present invention relates, moreover, to a process for packaging a product in a pouch according to Claim 10 and the following claims. 5 In particular, the process for packaging a product in a pouch preferably comprises at least one of the following steps:

The process comprises preferably at least one step of feeding a band of wrapping sheet unwound from a reel along an advancement path.

The process may comprise preferably at least the step of folding the0 band about a folding line oriented parallel to the advancement path so as to superimpose two band portions on top of one another.

As an alternative to the preceding step, the process may comprise preferably at least the step of joining to the band a further band of another wrapping sheet so as to obtain a band with the two wrapping sheets joined5 together along a direction oriented parallel to the advancement path and superimposed together at least partially, the two wrapping sheets forming two band portions superimposed on one another.

The process comprises preferably at least the step of forming in succession sealing lines which are transverse to the folding line or the longitudinal sealing line and which fix together the two superimposed band portions and define, preferably by a continuous movement, a succession of pouches connected to one another along the transverse sealing lines.

The process comprises preferably at least the step of dividing the band into the single pouches along the transverse sealing lines. 5 The process comprises preferably at least the step of dispensing a product into the single pouches (110).

The process comprises preferably at least the step of closing the single filled pouches (110).

The process envisages that the step of forming in succession the

5 transverse sealing lines includes the substep of arranging the band between a first and a second series of welding members situated opposite each other and carried by a drum rotatable preferably with a continuous movement and distributed around the rotation axis of the drum in corresponding positions and causing the band to advance around the rotation axis of the drum, the band lying along a theoretical surface parallel to the rotation axis of the drum.

The process envisages that the step of forming in succession the transverse sealing lines includes the substep of bringing in succession the second welding members against the first welding members, pressing the5 band between them and maintaining the first and second welding members in this condition for a predetermined time such that the transverse sealing lines are formed.

The claims below form an integral part of the teaching provided here. 0 Further characteristic features and advantages of the present invention will become clear from the following description provided purely by way of a non-limiting example, with reference to the accompanying drawings in which:

- Figure 1 shows in schematic form an example of the apparatus5 described here;

- Figure 2 shows a top plan view of a detail of the apparatus according to Figure 1;

- Figure 3 shows a welding unit for forming the transverse sealing lines of the package, according to a preferred embodiment of the apparatus described here;

- Figure 4 shows an axonometric view of a detail of the welding unit according to Figure 3;

- Figure 5 shows a pressing unit for a preferred embodiment of the apparatus described here; 5 - Figure 6 shows in schematic form a preferred mode of implementation of the packaging process described here;

- Figure 7 shows in schematic form a further mode of implementation of the process described here;

- Figures 8A, 8B, 8C show different examples of a pouch-type package.

In the following description various specific details intended to help fully understand the embodiments are illustrated. The embodiments may be realized without one or more of the specific details, or using other methods, components or materials, etc. In other cases, known structures, materials or operations are not shown nor described in detail so that various aspects of the embodiment may be more clearly understood.

The references used here are intended solely for easier illustration and therefore do not define the scope of protection or the extent of the embodiments.

As mentioned above, the solution described here refers to the sector of product packaging and relates, in particular, to an apparatus and a process for packaging a product in a pouch.

By way of example, Figure 8A shows a package 110 which can be made by means of the apparatus described here.

The package 110 comprises two wrapping portions 110A, HOB which are situated opposite each other, receiving the product in the space formed between them, and are connected together by a folding line 1101, two sealing lines 11011 parallel to each other and transverse to the folding line 1101, and a sealing line 110III parallel to the folding line 1101.

According to a variant (not shown), the packaging 110 may have - instead of the single folding line 1101 - a plurality of folding lines which define a bottom of the package which has a cross-section with W-shaped profile.

The designs shown are only some examples of pouch-like packages which can be made by means of the solution described here.

With reference now to Figures 1 and 6, the apparatus described here, which is denoted overall by the reference number 1, comprises:

- a unit 10 for feeding a band of wrapping sheet unwound from a reel, for feeding the band 100 along an advancement path K;

- a unit 20 for folding the band 100, for folding the band about a folding line 1011 oriented parallel to the advancement path K so as to superimpose two portions 100A, 100B of the band 100 on one another;

- a welding unit 40 for forming in succession sealing lines 100II which are transverse to the folding line 1001 and which fix together the two

5 portions 100A, 100B of the band 100 and define, preferably by a continuous movement, a succession of pouches 110 connected to one another along the transverse sealing lines 100II;

- a cutting unit 60 for dividing the band 100 into the single pouches 110 along the transverse sealing lines 100II;

- a filling unit 70 for dispensing a product into the single pouches 110;

- a further welding unit 80 for closing the single filled pouches 110.

Figure 6 shows in schematic form the steps of the process carried out by the apparatus 1. 5 In the light of the above, it can be understood that the folding line 1001 and the sealing lines 100II formed on the band 100 define in the single pouches 110 separated from the band following the cutting operation, the folding line 1101 and the sealing lines 11011 mentioned above with reference to Figure 8A. 0 The units 10, 20, 60, 70 and 80 may be of the conventional type and therefore further details will not be provided here.

With reference to Figures 2 to 4, in one or more preferred embodiments of the apparatus described here, the welding unit 40 comprises a drum 41 which is rotatable, preferably with a continuous5 movement, about a rotation axis I and which carries, on a peripheral region thereof, a series of welding members 42 which are distributed around the rotation axis I and face outwardly with respect to the drum I.

The rotatable drum 41, although in a preferred embodiment it has a continuous movement, in further embodiments could also have an alternating movement.

Furthermore, in one or more preferred embodiments, the welding unit 40 comprises a second series of welding members 43 which are distributed around the rotation axis I of the drum in positions corresponding to the members 42 of the first series mentioned above. 5 The welding members 43 when operated are arranged, in an operative position, opposite the welding members 42 so as to press the band 100 against them and form the sealing lines 10011.

The welding members 42, 43 may be, per se, of the known type, so as to perform heat- welding of the band or ultrasonic welding.

5 In one or more preferred embodiments, the welding members 43 are mounted on the drum 41 so as to be able to pivot about respective rotation axes h contained in a plane orthogonal to the rotation axis I of the drum.

By means of actuating means per se of the known type, for example cam means, the welding members 43 are operated so as to be rotated from a raised inoperative position into an operative position against the welding members 42.

With reference to Figure 2, during operation, the advancement path K extends along the peripheral region of the drum 41 defining a position Pl, in which the band 100 is brought into contact with the peripheral region5 of the drum, and a position P2,in which the band 100 is detached from this region so as to be directed towards the downstream unit of the apparatus.

The rotation of the drum 41 accompanies the advancing movement of the band 100.

At the same time, the aforementioned actuating means operate the0 welding members 43 so as to bring them, in succession, into the operative position, when the single welding member reaches a position P3 downstream of the position Pl, and bring them back, again in succession, into the inoperative position, when the single welding member 43 reaches a position P4 upstream of the position P2 (and downstream of the position5 P3).

The person skilled in the art will understand that the positions P3 and P4 determine the duration of the welding operation.

Preferably, the apparatus 1 is designed to provide the possibility of adjusting the positions P3 and P4 and/or their mutual distance. In one embodiment, the positions P3 and P4 may coincide with the positions Pl, P2, respectively.

In one or more preferred embodiments, the peripheral region of the drum 41 comprises a plurality of elements 44 for supporting the band 100, which are distributed around the rotation axis I of the drum, preferably in5 positions corresponding to the welding members 42. The supporting elements 44 define overall the lying surface of the band 100 along the peripheral region of the drum, indicated by the reference SI in Figure 1.

The supporting elements 44 each have an open frame which defines

5 two edges 44A parallel to each other and to the rotation axis I and spaced from each other along a chord of the circumference defined by the lying surface SI around the rotation axis I. A passage 44B, through which the welding member 42 reaches the band 100, is defined between the edges 44A.

Preferably, the welding members 42 are also mounted movably on the drum between an inoperative position, retracted with respect to the passage 44B, and an operative position in which the member 42 is inserted into the passage 44B, reaching the band 100.

Operation of the members 42 between these two positions may be5 performed by actuating means of the type known per se, for example cam means.

With regard to that stated above, operation of the welding members 42 will be synchronized with the welding members 43 in the same manner described above with reference to the positions Pl, P2, P3 and P4. 0 In one or more preferred embodiments, the radial position of the supporting elements 44 with respect to the rotation axis I of the drum is adjustable by means of an actuator.

During operation, this adjustment allows the pitch between the transverse sealing lines 100II formed on the band 100 to be adjusted. In5 fact, it will be noted that an increase, or on the other hand a reduction, in the radial distance of the supporting elements 44 results, correspondingly in an increase, or reduction, in the diameter of the circumference followed by the surface SI around the rotation axis I, this at the same time resulting in an increase, or a reduction, in the mutual distance of the sealing lines 100II formed along this circumference.

The adjustment in question may be performed both during programming of the apparatus 1 for the production of a new package design and during operation in order to compensate for the variations in speed of the band 100 during its advancing movement along the path K. 5 In this connection, the apparatus 1 may comprise a sensor 91 for detecting an advancement status of the band 100 m a position P5 of the advancement path K upstream of the position Pl on the drum 41 and downstream of the folding unit 20. For example, the sensor 91 may be an optical sensor designed to detect the passage of predetermined graphical

5 elements reproduced on one of the portions 100 A, 100B of the band.

The control unit 90 of the apparatus may be configured to drive the actuators for adjusting the radial positions of the supporting elements 44 depending on the signals received from the sensor 91, so as to obtain a predetermined pitch between the sealing lines 100II.

For example, the detection performed by the sensor 91 may indicate a distance of the band with respect to a reference position, along the advancement path K, and the control unit 90 may be configured to vary the radial positions of the supporting elements 44 so as to eliminate this distance. 5 With reference to Figure 4, in one or more preferred embodiments, each supporting element 44 is mounted on a bracket 45 movable on guides 47 radially with respect to the rotation axis I of the drum and operated by an actuator (not shown), preferably a linear actuator. On the bracket 45 there is also mounted, pivotably, the corresponding welding member 43, carried by0 a support 46 hinged about a respective axis h,

In this way, the welding members 43 follow the radial displacement of the supporting elements 44, therefore being immediately ready to operate on the new band lying surface defined by each new position.

On the other hand, the actuators of the welding members 42 vary5 their travel, adapting it to the new position of the supporting elements 44.

In one or more preferred embodiments, the apparatus 1 further comprises a pressing unit 50 positioned downstream of the welding unit 40 and upstream of the cutting unit 60.

The unit in question operates so as to stretch the band 100 and compensate for the deformations suffered by the band as a result of the treatment received in the welding unit 40.

In this connection, as seen above, at the welding unit 40 the band 100 is wound around the drum 41 and, in this condition, is pressed between the welding members 42, 43 so as to form the transverse sealing lines 100II.5 These operations may cause the formation of folds in the wrapping sheet in localized zones and, moreover, the generation of deformations m the sheet such as to impart to the band the curvature imposed by the lying surface S 1 of the welding unit 40.

The pressing unit 50 has precisely the function of eliminating the aforementioned folds and curvature.

The pressing unit 50 comprises first and second compression surfaces 51, 52, arranged opposite each other, for pressing the band 100 together.

The two surfaces 51, 52 extend along respective closed trajectories and are movable along the same trajectories.

Along a section the respective trajectories of the two compression surfaces 51, 52 follow profiles which are parallel and close together such that they are arranged opposite each other and define a passage 53 intended to be crossed by the band 100.

Along this section the compression surfaces 51, 52 define the band lying surface inside the pressing unit 60 - indicated by the reference number S2 in Figure 1 - and the advancement path K across the said unit.

The lying surface S2 of the pressing unit 50 has a curvature with a sign opposite to the curvature of the lying surface S 1 of the welding unit 40.

The compressive action of the two surfaces 51, 52 on the band 100 lying on the lying surface S2 performs the functions mentioned of stretching the folds and removing the curvature of the band.

In one or more preferred embodiments, the passage 53 between the two surfaces 51, 52 extends over an angular interval of between 30° and 320°, preferably between 90° and 270°, and even more preferably between 160° and 200°.

In one or more preferred embodiments, the compression surface 51 is defined by the side wall of a roller rotating preferably with a continuous movement around a rotation axis 13 defining the geometric axis of the lying surface S2 of the pressing unit 50.

On the other hand, in one or more preferred embodiments, the compression surface 52 is defined by a closed annular band which extends along a predetermined trajectory, along a section, coinciding with the trajectory K, and is movable along the said predetermined trajectory, operated by means known per se (for example a system of pulleys and deviating rollers).

In one or more preferred embodiments, the pressing unit 50 also performs an action for cooling the band 100.

For this purpose, the two compression surfaces 51, 52 are designed

5 to be arranged in a heat exchange condition with the band 100 so as to produce the cooling action indicated.

In one or more preferred embodiments, the two surfaces 51, 52 are defined by components - for example the aforementioned roller and band - made of metallic material.

In one or more preferred embodiments, the apparatus 1 further comprises a cooling system operationally associated with the two surfaces 51, 52. This cooling system may be per se of the known type. For example, it may envisage Peltier cells thermally connected to the two surfaces 51, 52. Alternatively, this system may instead operate with a cooling fluid, for5 example compressed air.

The cooling action indicated helps to stabilize the sealing lines 100II formed in the welding unit 40.

In one or more preferred embodiments, the apparatus 1 further comprises a welding unit 30 positioned downstream of the folding unit 20,0 for forming a longitudinal sealing line 100IV, parallel to the folding line 1001 and, preferably positioned in the immediate vicinity of, or superimposed on, the said folding line 1001.

The sealing line 100IV performs the function of fixing the geometry of the band after it has been folded by the folding unit 30, preventing in5 particular the two portions 100 A, 100B of the band from getting out of alignment with each other in the following welding unit 40.

This thus ensures an optimum quality of the package 110 made.

The welding unit 30 may be provided with welding means of the conventional type, for forming the sealing line 100IV. In the example shown (Figure 2), the unit 30 comprises heated, oppositely arranged rollers 31, 32 for performing heat- welding of the band 100. Alternatively, the unit 30 may instead comprise means for performing ultrasonic welding (generally, at least one sonotrode member and an anvil member).

In any case, the sealing means in question define two opposite5 working surfaces, intended to engage with the two opposite portions 100A, 100B of the band 100 in order to form a sealing line 100 VI of the desired height, during the continuous advancing movement of the band 100 along the advancement path K.

In view of the above, the packaging process performed by the

5 apparatus 1 involves the following steps:

- feeding the band 100 unwound from a reel along the advancement path K;

- folding the band 100 about the folding line 1001 oriented parallel to the feeding path K, so as to superimpose the two band portions 100A, 100B on one another;

- preferably, forming the longitudinal sealing line 100IV, oriented parallel to the folding line 1001, so as to fix together the two superimposed portions 100A, 100B;

- forming in succession the transverse sealing lines 100II, so as to5 form a succession of pouches 110 connected together along the sealing lines 100II;

- preferably, compressing the band 100 between the compression surfaces 51, 52 of the pressing unit 50;

- dividing the band 100 into the single pouches 110 along the0 transverse sealing lines 100II;

- dispensing a product into the single bags 110;

- closing the single filled bags, by means of the sealing lines 110III formed by the sealing unit 80.

Figure 8B shows the package 110 obtained by means of the process5 described. Compared to the package of Figure 8A, it therefore comprises, in addition, the sealing line 110IV next to the folding line 1101, which is derived from the line 100IV formed by the welding unit 30.

With reference to Figure 7, in an alternative embodiment, the apparatus 1 may comprise a second feeding unit 10'.

This second feeding unit 10' feeds a further band 100' of another wrapping sheet along the advancement path K, in order to form a band 101 composed of the two wrapping sheets joined together.

The band 100', as well as the band 100 fed by the feeding unit 10, in this case each have a width which is equal to the corresponding dimension5 of the final packaging 110. Accordmg to the alternative embodiment m question, the apparatus 1 does not have the folding unit 20 designed to superimpose two portions of a single band.

On the other hand, the two bands 100, 100' fed by the respective

5 feeding units 10, 10' are placed in contact with each other in a superimposed condition so that the respective longitudinal edges are at least partially aligned and, in this condition, the two bands 100, 100' are fixed together by means of the welding unit 30, which forms the sealing line 100IV. Upstream of the welding unit 30 conveying means may be provided for moving the two bands 100, 100' closer together. These means, together with the welding unit 30, in any case form part of a more general coupling unit which forms the band 101 from the two bands 100, 100', provided in the apparatus 1 according to this embodiment.

The band 101 thus obtained has two band portions 100A, 100B5 superimposed on each other, similar to the band 100 of the previously described embodiment.

It will be noted that in this case also the welding unit 20 performs the function of fixing together the portions 100A, 100B so as to prevent them from getting out of alignment during the following process steps. 0 Figure 8C shows the packaging 110 obtained by the apparatus 1 according to a further embodiment.

In one or more preferred embodiments, the apparatus 1 is designed to control the advancing movement of one or both the bands 100, 100' so that they are fed with a predefined relative synchronism. 5 In particular, in one or more preferred embodiments (Figure 7), the apparatus 1 comprises at least one sensor 92 for detecting an advancement status of the band 100 and/or of the further band 100' into a position upstream of the second welding unit 40. Furthermore, the control unit 90 is configured to drive the motor Ml, which performs rotation of the reel of the feeding unit 10, and/or the motor M2, which performs rotation of the reel of the feeding unit 10', depending on the advancement status detected by the sensor 92, so as to ensure a predefined synchronism between the rotation of the reel of the band 100 and the rotation of the reel of the band 100'.

In a similar maimer to the aforementioned sensor 91, the sensor 925 may for example be an optical sensor for detecting the passage of predetermined graphical elements reproduced on one of the two sides of the bands 100, 100'.

For example, the detection performed by the sensor 92 may indicate a distance between the positions of the bands along the advancement path

5 K, and the control unit 90 may be configured to accelerate and/or decelerate the motor Ml and/or the motor M2 so as to eliminate this distance.

The control unit 90 of the apparatus may consist of a single module, as in the example of Figure 1, or may consist of a plurality of separate control modules, each for implementing a respective function from among those indicated above.

Moreover, the apparatus, in a further embodiment, may preferably comprise a coupling unit 30 for joining to the band 100 a further band 100' of a wrapping sheet thus forming a band 101 with two wrapping sheets joined together, having a longitudinal sealing line 100IV which is oriented5 parallel to the advancement path K and fixes together the two wrapping sheets and two band portions 100A, 100B which are superimposed on each other.

It is clear that the present invention achieves the predefined objects and also offers various advantages including those of being able to adjust0 the time available for welding in a very precise maimer, activating after a predefined time period operation of the welding members 43, which pass from the operative position against the welding members 42 to the inoperative raised position. This is particularly evident if operation of the welding members 43 is performed, for example, using pneumatic or electric5 drives which are connected to a control unit which may be configured to control the raising instant. Such control of the raising movement of the welding members 43 is also able to ensure protection of the film against possible burning during pauses in operation of the apparatus which could occur as a result of a stoppage.

Obviously, without altering the principle of the invention, the constructional details and embodiments may vary, even greatly, with respect to that illustrated here purely by way of a non-limiting example, without thereby departing from the scope of the invention, as defined by the accompanying claims. 5

Claims

1. Apparatus (1) for packaging a product in a pouch, comprising:

- at least one unit (10) for feeding a band (100) of wrapping sheet unwound from a reel, for feeding the band (100) along an advancement path

5 (K);

- a unit (20) for folding the band (100), for folding the band about a folding line (1001) oriented parallel to the advancement path (K) so as to superimpose two band portions (100 A, 100B) on one another, or a coupling unit (30) for joining to the band (100) a further band (100’) of another wrapping sheet to obtain a band (101) with the two wrapping sheets joined together along a direction oriented parallel to the advancement path (K) and superimposed together at least partially, the two wrapping sheets forming two band portions (100A, 100B) superimposed on one another, 5 a welding unit (40) for forming in succession sealing lines (100II), which are transverse to the advancement path (K) and which fix together the two superimposed band portions (100A, 100B) and define, preferably by a continuous movement, a succession of pouches (110) connected to one another along the transverse sealing lines (100II); 0 a cutting unit (60) for dividing the band into the single pouches (110) along the transverse sealing lines (110II); a filling unit (70) for dispensing a product into the single pouches (110); a further welding unit (80) for closing the single filled5 pouches; wherein the welding unit (40) comprises a drum (41) which is rotatable, preferably with a continuous movement, about a rotation axis (I) and which carries, on a peripheral region thereof along which the band advancement path (K) extends, a series of welding members (42) which are distributed around the rotation axis (I) and face outwardly with respect to the drum (41), for forming the transverse sealing lines (100II) on the band (100; 101) lying along a theoretical surface (SI) parallel to the rotation axis (I) of the drum, the apparatus being characterized in that the welding unit (40)5 comprises a second series of welding members (43) which are distributed around the rotation axis (I) of the drum m positions corresponding to the members (42) of the first series and arranged, in an operative position, opposite the welding members (42) of the first series, for pressing the band (100; 101) against the welding members (42) of the first series.

5 2. Apparatus according to claim 1, wherein the welding members

(43) of the second series are mounted on the drum (41) so as to be able to pivot about respective rotation axes (12) that are contained in a plane orthogonal to the rotation axis (I) of the drum, between an inoperative position and the operative position.

3. Apparatus according to claim 1 or 2, wherein the peripheral region of the drum comprises a plurality of elements (44) for supporting the band, which are distributed around the rotation axis (I) of the drum and which have respective portions (44A) for supporting the band, defining overall the band lying surface (SI) which is parallel to the rotation axis (I)5 of the drum.

4. Apparatus according to claim 3, wherein the supporting elements

(44) are arranged around the rotation axis (I) of the drum in positions corresponding to the welding members (42) of the first series, and each define a passage (44B) through which the respective welding member (42)0 of the first series reaches the band (100; 101).

5. Apparatus according to claim 3 or 4, wherein the radial position of each supporting element (44) with respect to the rotation axis (I) of the drum is adjustable by means of an actuator.

6. Apparatus according to claim 5, comprising a control unit (90)5 configured to drive the actuators for adjusting the radial positions of the supporting elements (44) as a function of a signal indicative of a predetermined pitch between a transverse sealing line (100II) and the next one along the band advancement path (K).

7. Apparatus according to claim 5 or 6, wherein each supporting element (44) is carried by a bracket (45) that is radially movable with respect to the rotation axis (I) of the drum, being driven by an actuator, and wherein the corresponding welding member (43) of the second series is mounted on said bracket (45).

8. Apparatus according to any one of the preceding claims, wherein5 the welding members (42, 43) of the first and the second series are mounted PCT/IB2021/061497 so as to be movable on the drum (41) between an inoperative position and an operative position in which they are arranged on the band lying surface (si).

9. Apparatus according to claim 6, comprising a sensor (91) for

5 detecting an advancement status of the band in a position (P5) of the advancement path (K) that is upstream of the drum (41) and downstream of the folding unit (20) or the coupling unit (30), and wherein the control unit (90) is configured to drive the actuators for adjusting the radial positions of the supporting elements (44) as a function of the detected advancement status, so as to obtain a predetermined pitch between a transverse sealing line and the next one along the band advancement path (K).

10. Process for packaging a product in a pouch, comprising the steps of: feeding a band (100) of wrapping sheet unwound from a reel5 along an advancement path (K); folding the band (100) about a folding line (1001) oriented parallel to the advancement path (K) so as to superimpose two band portions (100 A, 100B) on one another, or joining to the band (100) a further band (100’) of another wrapping0 sheet so as to obtain a band (101) with the two wrapping sheets joined together along a direction oriented parallel to the advancement path and superimposed together at least partially, the two wrapping sheets forming two band portions (100A, 100B) superimposed on one another, forming in succession sealing lines (100II), which are5 transverse to the folding line (1001) or to the longitudinal sealing line (100IV) and which fix together the two superimposed band portions (100A, 100B) and define, preferably by a continuous movement, a succession of pouches (110) connected one to another along the transverse sealing lines (100II); dividing the band into the single pouches (110) along the transverse sealing lines (110II); dispensing a product into the single pouches (110); closing the single filled pouches (110); wherein the step of forming in succession the transverse sealing lines5 (100II) includes: PCT/IB2021/061497 arranging the band (100; 101) between a first and a second series of welding members (42, 43) which are situated opposite one another and are carried by a rotating drum (41), preferably with a continuous movement, and are distributed about the rotation axis (I) of the drum in

5 corresponding positions, and advancing the band (100; 101) around the rotation axis (I) of the drum, the band (100; 101) lying along a theoretical surface (SI) parallel to the rotation axis (I) of the drum, and bringing in succession the second welding members (43) against the first welding members (42) so as to press the band (100; 101) between them, and maintaining the first and the second welding members (42, 43) in this condition for a predetermined time such that the transverse sealing lines (100II) are formed.

11. Process according to claim 10, including:

- varying the radial distance of the band lying surface (SI) from the5 rotation axis (I) of the drum as a function of a signal indicative of a predetermined pitch between a transverse sealing line (100II) and the next one along the band advancement path (K).

12. Process according to claim 10 or 11, including:

- by means of a sensor (91), detecting an advancement status of the band in a position (P5) of the advancement path (K) that is upstream of the drum (41) and downstream of a folding unit (20) in which the band is folded, and

- varying the radial distance of the band lying surface (SI) from the rotation axis (I) of the drum as a function of the detected advancement5 status, so as to obtain a predetermined pitch between a transverse sealing line ( 10011) and the next one along the band advancement path (K).