GB2368058A - Automatic Packaging Machine for paper rolls - Google Patents

Abstract

An automatic packaging machine comprises a feeding conveyor 44, a rotating structure 46 with a plurality of packaging modules 50 and a packaging conveyor 36. The structure 46 receives a product and a wrapping film from conveyor 44 into a packaging module 50 wherein the film forms a U-shape around the product. The structure 46 comprises stations for folding and sealing the ends of the film together before transferring the product to conveyor 36 where the sides of the film are folded and sealed. The packaging modules 50 are mobile with respect to structure 46 and are adaptable to receive products of various sizes. Each module 50 preferably comprises a motor driven gear wheel (62, fig. 7), which engages an annular rack (58) on structure 46, idler wheels (56), which engage either side of an annular rail (48) on structure 46 and act to guide the modules 50, and a pair of adjustable parallel plates (64) and conveyors (66) adaptable to receive and hold the product.

Description

PACKAGING MACHINE AND PROCESS The present invention relates in general to the field of packaging of products using a film of flexible material. In particular, the invention has been developed with regard to the packaging of rolls of paper using a film of plastic material.

Present-day automatic packaging machines for the packaging of rolls of paper are generally machines of a linear type, i. e. , machines in which the flow of products is moved along a series of rectilinear directions during the packaging cycle. Machines with rectilinear flow of products have evolved over the years to yield increasingly high levels of productivity and, above all, to simplify, and reduce the time necessary for, the operations of change of format of the machine. Although present-day packaging machines with rectilinear flow of products afford a high productivity and enable the operations of change of format to be carried out very rapidly and efficiently, there exists the possibility of improving the production capacity even further by using a packaging cycle that envisages a rotating movement of the products to be packaged during one part of the packaging cycle. Automatic packaging machines are known that comprise a rotating structure carrying a plurality of packaging modules, each of which is designed to receive a product to be packaged with a corresponding film of packaging material. Existing rotary packaging machines are generally designed for wrapping products of small volume and, in almost all cases, they are machines that carry out wrapping of individual products or bundles of products having a monolithic structure that may be likened to individual products. Existing rotary machines are generally unsuitable for carrying out packaging of intrinsically unstable products, such as packs made up of two or more rolls of paper. Rotary machines of the known type may be divided basically into two categories: - continuous-wrapping rotary machines; and - rotary machines with alternating feed.

In the machines in which the wheel carrying the packaging modules has an alternating motion, the wheel stops periodically at the points for introduction of the products to be packaged. The rotating structure thus undergoes, during its operation, a continuous series of accelerations and decelerations which involve the rotating structure as a whole. The rotating structure of the machines of this type has a high moment of inertia and requires high operating torques.

During operation, problems of instability and vibrations can easily arise, which set a limit to the working rate.

In rotary machines with continuous feed the rotating structure carrying the various packaging modules advances in a continuous way, and a feed assembly is provided which inserts the products sequentially into the packaging modules, the said feed assembly having an oscillating motion in order to follow the movement of the wheel. In this case, the major problem is represented by the excessive stress to which the feed assembly is subjected. Also in this case, the excessive dynamic stresses on the feed assembly limit the maximum working speed of the machine.

The aforesaid reasons have up to now prevented the use of rotary packaging machines for packaging products of large dimensions. A further limit to the application of rotary packaging machines to the field of packaging of rolls of paper is represented by the fact that rotary machines of the known type do not generally allow operations of change of format to be carried out rapidly.

The purpose of the present invention is to provide a process for packaging products that is particularly suited to being implemented on a rotary machine, as well as an automatic packaging machine of a rotary type that enables the problems referred to above to be solved.

According to the present invention the above and other purposes are achieved by a packaging process and an automatic packaging machine having the characteristics that form the subject of the claims.

The present invention will now be described in detail with reference to the attached drawings, which are provided purely by way of non-limiting example, and in which: - Figures 1, 2 and 3 are schematic perspective views illustrating the main steps of the packaging process according to the present invention; - Figure 4 is a schematic perspective view illustrating the sequence of formation of a wrapper carried out in a rotary packaging system according to the invention; - Figure 5 is a schematic side view according to the arrow V of Figure 4 ; - Figure 6 is a schematic side view of a rotary packaging machine according to the present invention; - Figures 7 and 8 are schematic side views illustrating, at a larger scale, the parts indicated by the arrows VII and VIII in Figure 6 ; - Figures 9 and 10 are partially sectioned side views of a packaging module during two steps of the cycle of formation of a wrapper ; - Figure 11 is a side view of a packaging module during a further step of the cycle of formation of the wrapper; - Figure 12 is a partially sectioned perspective view of a packaging module of the machine of Figure 6; - Figure 13 is a schematic view according to the line XIII-XIII of Figure 12; - Figure 14 is a schematic view similar to that of Figure 12 illustrating the packaging module arranged for operating with products having different formats; and

- Figure 15 is a schematic sectional view according to the line XV-XV of Figure 12.

Figures 1, 2 and 3 are schematic illustrations of a process for wrapping a product P with a film F of packaging material, typically a film of polyethylenebased plastic material. In the example illustrated in the figures, the product P to be packaged consists of three rolls R of paper set parallel to one another. The process according to the present invention has been developed specifically for packaging of rolls of paper, but may be used also for packaging products of a different type. The process according to the invention is suitable for packaging packs made up of a variable number of rolls R and with rolls of variable shape and size. As is illustrated in Figure 1, a first step in the process of packaging the pack P envisages wrapping the film F partially around the rolls. Once partial wrapping is completed, the film F presents two plane faces 10 that extend on opposite sides of the pack P and are radiused together by an arched portion 12 which wraps an end roll R according to an arc of 1800. Each plane face 10 has two side edges 14 which project laterally beyond the pack P, and a front edge 16 that projects for a pre-set length beyond the corresponding front side of the pack P.

Again with reference to Figure 1, on the film F there are formed a first pair of lateral folds 18, which are obtained by squeezing the side edges of the film F located in the arched region 12 against the sides of the pack P, as indicated schematically by the arrows 20 in Figure 1.

In a step following the one represented in Figure 1, the front flaps 16 are folded in succession against the arched edge of the pack P. Following upon this folding operation, the two flaps 16 partially overlap one another and are sealed along a sealing line indicated by 22 in Figure 2. Figure 2 illustrates the pack being packaged in a position that is turned over through 1800 about a horizontal axis with respect to the configuration illustrated in Figure 1. After execution of the seal 22, a second pair of lateral folds 24 are made by folding the side edges of the film F located in the area corresponding to the arched part of the pack P against the sides of the pack P. Next, the top and bottom side flaps 14 are folded against the sides of the pack P, as illustrated in Figure 3 to form respectively, third and fourth lateral folds 26,28 (Figure 3). Following upon this latter folding operation, the folded side edges 26,28 partially overlap one another and are sealed to complete closing of the wrapper.

Figures 4 and 5 are schematic illustrations of the way in which the cycle of forming the wrapper described hitherto is implemented in a rotary machine. With reference to these figures, the packs P that are to be packaged are fed in succession in the direction indicated by the arrow A through a vertical plane in which a film F is withheld. For example, the film F may be withheld temporarily along its top and bottom edges in a vertical position and is released when a pack P passes through the plane of the film F. During passage of a pack P through the plane of the film, the film F sets itself around the pack, and, at the same time, the first pair of folds 18 is formed-in the way better described in what follows-owing to the fact that the packs P are made to advance by a pair of belts that grip them along their sides. Each pack P with the corresponding film is inserted into a packaging module that rotates about a horizontal axis in the direction indicated by the arrows B. In the positions indicated by 2 and 3, the folding of the'front edges 16 is performed in succession within the packaging module.

Next, in the position indicated by 4, sealing of the front edges 16 is carried out. Preferably, this sealing operation is performed in two successive steps indicated by 4'and 4"in Figure 5. The first step envisages the sealing operation along the portions of the sealing line that are free from retention means that withhold the edges 16 of the film F in position. After a preliminary tacking, the means that withhold the edges 16 can be brought into a non-operative position to leave the entire sealing line free. In this way, in the next position, indicated by 4"in Figure 5, a second sealing operation is performed, which completes the preliminary tacking seal.

Subsequently, in the position designated by 5, following upon a further rotation of the packaging module, the pack arrives at an unloading station in which it is ejected from the packaging module by means of a movement in the direction indicated by the arrow C in Figures 4 and 5. During the movement of ejection, the second pair of folds 24 is formed, and, in the position indicated by 6, the side folds 26 and 28 are made by causing the pack to advance between stationary folding surfaces according to methodologies that are in themselves known. The folds 26 and 28 are then sealed in a conventional way to complete formation of the pack.

Figure 6 is a schematic representation of an automatic packaging machine of the rotary type which enables the packaging process described above to be implemented. The packaging machine according to the present invention comprises an assembly 30 for feeding the products to be packaged, an assembly 32 for feeding the films of packaging material, a rotary unit 34 for forming the wrappers, and an output section 26 along which the side folds 26,28 are made and the side folds that complete closing of the packages are also made.

The feeding assembly 30 comprises a belt-conveyor device 38 designed to divide a continuous row of rolls into groups of products to be packaged set at equal distances apart, each group being made up of a pre-set number of rolls. The conveying device 38 has an end section 40 which is set facing the film-feeding assembly 32. The said assembly carries out cutting to measure of successive portions of a continuous ribbon of a packaging material and feeds in sequence the individual portions in a direction orthogonal to the plane of representation of Figure 6. The film-feeding assembly 32 withholds each film in a vertical plane in front of the output section 40 of the feed assembly 30.

Immediately downstream of the plane in which the films of packaging material are withheld, a conveyor 42 is set which is equipped with a pair of parallel belts 44 (only one of which may be seen in the representation of Figure 6), which are designed to grip the products with the corresponding film along the sides of the products and to cause the, products to advance in succession towards the rotating packaging unit 34.

The packaging unit 34 comprises a rotating structure 46 which, in operation, is driven in rotation at a constant speed about a horizontal axis orthogonal to the plane of representation of Figure 6. The rotating structure 46 comprises an annular guide 48 having the shape of a rail. A plurality of packaging modules 50 are mounted so that they can slide on the annular guide 48.

With reference to Figures 8 and 15, each packaging module 50 comprises a guiding and actuating section 52 which engages the guide 48. Figure 8 illustrates only the packaging module located at the product-insertion station. For the remaining modules, only the respective guiding and actuating sections 52 are illustrated. The guiding and actuating section 52 of each module 50 comprises a supporting plate 54 carrying two pairs of idle wheels 56 which engage, on opposite sides, the circular rail 48 of the rotating structure 46. The rotating structure 46 comprises a rack 58 having an annular shape, which is fixed in a position alongside the guide rail 48. The supporting plate 54 of each guiding and actuating section 52 carries an electric motor 60 which drives in rotation a gear wheel 62 that engages the annular rack 58. Each module 50, by means of the respective motor 60, can be moved independently of the other modules along the guide rail 48.

With reference to Figure 6, during operation the rotating structure 46 rotates at a constant speed. Each module, according to its position, may have, with respect to the rotating structure 46, a relative speed which is either positive or negative. In the case where a module 50 has a zero speed with respect to the rotating structure 46, it moves at the same angular speed as the rotating structure 46 in a stationary reference system. In the case where a module 50 has an angular speed equal and opposite to the angular speed of the rotating structure 46, it is stationary with respect to a stationary reference system. Finally, in the case where a module 50 has a speed concordant with the angular speed of the rotating structure 46, it moves, with respect to a stationary reference system, at a speed higher than that of the rotating structure 46. With reference to Figure 6, the operating cycle of each module 50 with respect to a stationary reference system envisages a stop at the product-loading station, an acceleration until the speed of the rotating structure 46 is reached, a possible movement at a constant speed equal to the speed of the rotating structure, a deceleration, and a second stop at the product-output station 36, a further acceleration until the speed of the rotating structure 46 is reached again, a further movement at a constant speed, followed by a second deceleration and a new stop at the loading station. Each of the modules 50 cyclically performs stops, accelerations, decelerations and successive stops, and the movements of all the modules 50 are controlled by a control unit that actuates the motors 60 of the individual modules 50 according to the positions of the latter. The positions of the modules 50 can be detected by means of sensors located in stationary positions, or else can be calculated according to the signals supplied by encoders associated to the motors 60 that actuate the modules 50. The duration of the time interval during which each module 50 is stationary in the product-input or product-output station is determined in such a way as to be roughly equal to the time necessary for inserting a product into the module and for unloading a partially completed wrapper from the module itself.

Figure 7 illustrates an operating position in which a module 50 is stationary in the station, designated by 63, for insertion of the products to be packaged, in a position where it is aligned to the conveying device 42 equipped with motor-driven belts 44 that act on the sides of the products to be inserted.

As illustrated in Figure 7, during the step of insertion of a product to be packaged into the module 50, the rotating structure 46 carries on moving at a constant speed in the direction indicated by the arrow B, whilst the module 50 that is to receive a product to be packaged moves with respect to the rotating structure 46 with an equal and opposite speed. In this way, in a stationary reference system, the module 50 remains stationary in a position where it is aligned to the insertion station 63. Each module 50 is equipped with a pair of parallel plates 64 set at a distance apart from one another that is equal to the height of the products and with a pair of motor-driven belts 66 (only one of which is shown in Figure 7) which grip the product on its sides to insert it into the module and, in the unloading step, to extract the product. The structure and operation of the belts 66 will be described in greater detail in what follows. Again with reference to Figure 7, the end part of the feed assembly 30 is provided with a top sliding surface 68 and a bottom belt conveyor 70 which causes a group of rolls R constituting the products to be packaged to advance in a direction orthogonal to a film F of packaging material which is withheld in a stationary position in front of the end part of the feed assembly 30. Set immediately downstream of the plane of the film F is the conveying device 42, which comprises a pair of horizontal guiding surfaces 72 and a pair of motordriven conveyor belts 44 that act on the sides of the rolls R. It will be appreciated that, during passage of the product P to be packaged through the plane of the film F, the film F wraps around the product, as illustrated in Figure 7. Given that the film F has a width greater than the width of the rolls R, the parts of the film F that project laterally beyond the rolls R and are set in a position corresponding to the motordriven belts 44 are folded against the corresponding sides of the first roll so as to form the first pair of folds, designated by 18 in Figure 1.

Figure 8 illustrates the step in which the product to be packaged with the corresponding film F has been inserted inside the packaging module 50. The side belts 66 of the packaging module 50 pick up the rolls at output from the conveyor 42 and feed them towards the inside of the module. The distance of advance of the product P inside the module depends upon the length of the product, which in turn depends upon the diameter of the rolls making up the product P. During insertion of the product inside the module 50, the motor-driven belts 66 of the module 50 withhold the rolls at the sides and maintain the first pair of folds 18. As may be seen in Figure 8, the front flaps 16 of the film F project beyond the product P outside the module 50.

With reference to Figures 9, 10 and 11, there follows a description of the operating sequences that enable folding of the front edges 16 of the film F to be obtained so that the said front edges overlap. With reference to Figure 9, each packaging module 50 comprises a folding device 74, in turn comprising a folding blade 76 carried by a lever 78 pivoted about a fixed shaft 80 carried by the supporting structure of the module 50. The lever 78 is mobile between an inoperative position, illustrated in Figure 9, and an operative position, illustrated in Figure 10. Movement of the lever 78 between the said positions is, for example, controlled by a hydraulic cylinder 82 connected to the lever 78 by means of a second lever 84. The folding device 74 is in the inoperative position illustrated in Figure 9 during the step of insertion of the product inside the module. Once insertion of the product and of the film of packaging material has been completed, the hydraulic actuator 82 is extended so as to bring the folding device 74 into the operating position. As may be seen from a comparison between Figure 9 and Figure 10, during movement from the inoperative position of Figure 9 to the operative position of Figure 10, the folding blade 76 brings the edge 16 of the film F into contact with the roll R. The first flap 16 of the film F is then folded and kept in contact with the roll R, whereas, as illustrated in Figure 10, the second flap 16 is still free. The operations illustrated in Figures 9 and 10 are carried out during a step in which the module 50 moves from the product-insertion station 64 in a direction concordant with the direction of rotation of the rotating structure 46. During this rotary movement, each module 50 encounters a stationary folding device 86 set in a position which is reached by the module 50 after folding of the first flap 16 has been completed. As may be seen in Figure 11, the stationary folding device 86 brings the second flap 16 into a position where it overlaps the folding blade 76 which withholds the previously folded flap. A sealing device 88 is set in a stationary position immediately downstream of the stationary folding device 86. After folding of the second flap 16 of the film F, the module 50 moves away from the stationary folding device 86 and moves into a position corresponding to the sealing device 88. The said sealing device is arranged for carrying out preliminary sealing or tacking of the two flaps 16 of the film F only along areas where the said flaps are in direct contact with one another, i. e. , where there is no interposition of the folding blade 76. After the said tacking operation has been performed, the blade 76 moves into the inoperative position, and a second sealing operation is performed by a second stationary sealing device (not illustrated), which completes sealing of the tacked areas to form a continuous sealing line 22, as illustrated in Figures 2 and 3.

According to another aspect of the present invention, each packaging module 50 is provided with adjustment means for adapting the dimensions of the module to those of the product to be packaged. The adjustment means of each module 50 are controlled in a centralized way by a main control unit of the system. The machine is able to adapt automatically to a new format without any need for manual intervention on the various modules. In what follows the structure of a packaging module and of the means that enable changeof-format adjustments to be carried out will be described in detail.

With reference to Figures 12 to 15, each packaging module 50 comprises a pair of lateral supporting walls 90, which are fixed, by means of a transverse element 92, to the plate 54 carrying the wheels 56 that engage the annular guide 48 of the rotating structure 46. Each module 50 comprises a pair of guide plates 64 that are parallel to one another and are set orthogonally to the side walls 90. The guide plates 64 define opposed containment surfaces which are set at a distance apart from each other that is equal to the height of the product to be packaged. In the case of a package of rolls consisting of a single layer of rolls, the distance between the plates 64 is roughly equal to the diameter of each roll of the package. The positions of the plates 64 with respect to one another can be adjusted in a direction orthogonal to the plane of the plates themselves to enable adaptation of the module 50 to products having different depths. A preferred embodiment of the adjustment mechanism is illustrated in Figures 12,13 and 14. With reference to the said figures, each plate 64 is connected to the supporting side walls 90 by means of an articulated-quadrilateral device comprising, for each side wall 90, a pair of arms 94, each of which has one end articulated to the plate 64 and the opposite end articulated to the respective supporting wall 90. Each arm 94 has a toothed portion 96 which meshes with a toothed portion 96 of a corresponding arm 94 connected to the plate 64 that is set opposite. The movement of adjustment is controlled by an electric motor 98 (Figures 13 and 14) articulated to a supporting side wall 90 and connected to a screw 100 which engages a threaded element articulated to one end of one of the arms 94. The articulated-quadrilateral structure of the adjustment mechanism guarantees that the two plates will always move parallel to one another during the movement of adjustment. In Figure 14, the solid line and the dashed line illustrate two different operating positions of the plates 64. It may be noted that the adjustment mechanism described moves the two plates 64 in a symmetrical way with respect to a middle plane.

As has already been described previously, each module 50 comprises a pair of conveyor belts 66 designed to grip a product to be packaged on its sides in order to move the product towards the inside of the module 50 during the insertion step and towards the outside of the module during the unloading step. Each conveyor belt 66 forms a continuous loop and cooperates with a return idler 104 and a motor-driven pulley 106. A controlling electric motor 108 is set coaxially to each pulley 106. The shafts for rotation of the return idler 104 and of pulley 106 are carried by a plate-shaped support 110. The said support moreover carries the motor 108 that drives the pulley 106. As may be seen in particular in Figure 15, the two belts 66 have respective rectilinear branches that are set parallel to and facing one another. The distance between said rectilinear branches of the belts 66 must be roughly equal to the width of the product to be packaged. To enable adaptation of the module 50 to products having different widths, the plate-shaped supports 110 carrying the belts 66 are mobile in a direction orthogonal to the rectilinear branches of the belts 66. As illustrated in Figure 15, the supporting side walls 90 of each module 50 carry a transverse guide 112, which is fixed with respect to the walls 90. The plate-shaped supports 110 engage in a sliding way the transverse guide 112. Movement of the plate-shaped supports 110 is controlled by a transverse screw 114 having two threaded portions 114a and 114b with opposite directions of winding of the thread. The two threaded portions 114a and 114b engage respective internal screws 116 carried by the plate-shaped supports 110. With reference to Figures 12 and 15, the screw 114 is carried, in such a way that it can freely turn about its own axis, by the supporting side walls 90 and is driven in rotation by an electric motor 118, for example by means of a toothed belt 120. It will be realized that rotation of the screw 114 in one direction or in the opposite direction brings about a movement of relative approach or recession between the plate-shaped supports 110, which enables the desired distance between the opposed branches of the belts 66 to be set.

A third adjustment is the one that enables the module 50 to adapt to products having different lengths. In the case of products consisting of a certain number of rolls there is a variation in the length of the product when the number of rolls varies or when the diameter of the rolls themselves varies. To adapt the module to a variation in the diameter of the product to be packaged, it is sufficient to vary the operating range of the belts 66. Given that the said range is controlled by the motors 108, a change in length of the products to be packaged simply requires a change in the number of revolutions that the motors 108 must perform during insertion of a product to be packaged into the module. The motors 108,118 and 98 that control the adjustment movements necessary for changing the format of the module are electronically controlled by a central control unit (not illustrated) which drives the motors of all the machine modules. The command signals can be sent to each module by means of wireless signal-transmission systems, for example via radio or infrared transmission systems. Electrical supply of the motors can, instead, be sent to the various modules via sliding contacts provided on the rotating structure 46.

Claims (14)

1. A process for automatic packaging of products (P), in particular for packaging products (P) consisting of one or more rolls (R) of paper, comprising the steps of: - setting a film (F) of packaging material in a plane ; - feeding a product (P) to be packaged through the plane of the film (F) ; - picking up the product (P) and the film (F) downstream of the aforesaid plane by means of a conveying device (44) which acts on opposed sides of the product (P) and forming a first pair of side folds (18) as a result of the gripping of the product (P) by said conveying device (44); - inserting the product to be packaged into a packaging module (50) which turns about an axis orthogonal to the direction of advance of the products ; - folding a first open flap (16) of the film (F) against the product ; - folding a second open flap (16) of the film (F) over the first open flap (16); - sealing said flaps (16) together ; - extracting, from the packaging module (50), the product (P) with the corresponding film (F) forming a partially closed wrapper, and forming a second pair of side folds as a result of the gripping of the partially packaged product by a conveying device (36) acting on opposed sides of the product; and - forming a third pair of side folds (26) and a fourth pair of side folds (28) to complete closing of the wrapper.

2. The process according to Claim 1, characterized in that the operation of folding a first open flap (16) of the film is performed by means of a folding device carried by the aforesaid packaging module.

3. The process according to Claim 2, characterized in that the aforesaid operation of folding the second open flap (16) of the film onto the first open flap (16) is performed as a result of the movement of the packaging module (50) with respect to a stationary folding device (86).

4. The process according to Claim 1, characterized in that it comprises carrying out a preliminary tacking together of the aforesaid open flaps, the said operation being performed while the first open flap (16) is kept pressed against the product by the aforesaid folding device (74) carried by the packaging module, and carrying out a second seal between the first flap and the second flap after the aforesaid folding device (74) carried by the packaging module (50) has been brought into an inoperative position.

5. An automatic packaging machine, in particular for the packaging of rolls of paper, comprising a rotating structure (46) carrying a plurality of packaging modules (50), each of which is designed to receive a product (P) to be packaged together with a film (F) of packaging material, characterized in that each of said packaging modules (50) is mobile with respect to the rotating structure (46) and is provided with its own actuating means (60,62) designed to control movement of the module (50) along the rotating structure (46).

6. The machine according to Claim 5, characterized in that, during operation, the individual modules (50) each have different speeds with respect to the rotating structure (46).

7. The machine according to Claim 5, characterized in that the aforesaid actuating means (60,62) of each packaging module (50) are able to move the respective module (50) with respect to the rotating structure (46) at a speed equal and opposite to the speed of rotation of the rotating structure (46), so that the module (50) is stationary in a stationary reference system for carrying out operations of loading and unloading of the products (P).

8. The machine according to Claim 5, characterized in that the aforesaid rotating structure (46) comprises an annular rail (48), and in that each module (50) comprises a guiding and actuating section (52) equipped with idler wheels (56) that engage on opposite sides the aforesaid annular rail (48).

9. The machine according to Claim 8, characterized in that the aforesaid annular structure (46) comprises an annular rack (58), and in that the aforesaid guiding and actuating section (52) of each module (50) carries a motor-driven gear wheel (62), which engages the aforesaid rack (58).

10. An automatic packaging machine comprising a rotating structure (46) carrying a plurality of packaging modules (50), each of which is designed to receive a product (P) to be packaged together with a film (F) of packaging material, characterized in that each packaging module (50) is provided with adjustment means for adapting the dimensions of the module (50) to the dimensions of the product (P) to be packaged along three mutually orthogonal directions.

11. The machine according to Claim 10, characterized in that each packaging module (50) comprises a pair of plates (64) that are parallel to one another, and an adjustment device (94) in the form of an articulated quadrilateral controlled by an electrical actuator (98) designed to adjust the distance between said plates (64).

12. The machine according to Claim 10, characterized in that each packaging module (40) comprises a pair of conveyor belts (66) equipped with respective rectilinear branches that are parallel to one another, and adjustment means (114,118) designed to adjust the distance between said parallel branches of the conveyor belts (66).

13. The machine according to Claim 12, characterized in that each of said conveyor belts (66) is driven by an electronically controlled electric motor designed to adjust the conveying range of the respective belt according to the length of the product to be packaged.

14. A machine substantially as described with reference to the accompanying drawings.