METHOD FOR MAKING A PACKAGE FOR GROUPS OF PRODUCTS AND MACHINE IMPLEMENTING THE METHOD

Description

Technical field

[0001] This invention relates to a method for making a package for groups of products for sanitary use and relative machine implementing the method, in particular, but without restricting the scope of the invention, rolls of "tissue" products such as, for example, rolls of paper for sanitary and/or household use or unwoven products such as nappies.

Background art

[0002] More specifically, this description focusses attention on bagging machines which are, usually, used for wrapping a certain number of groups of products already packed using plastic film, but without limiting the range of protection in question, since the groups of products can also be a plurality or batches of loose products.

[0003] These groups of products are grouped together in accordance with formats of pre-defined batches and then fed, in succession, in a tubular wrapping of film.

[0004] These bagging machines, which define, usually, an end station of machines for making the above-mentioned groups of products, bag the groups of products in tubular wrappers defined automatically by the bagging machine on the products to be wrapped.

[0005] Such machines are known from the patent documents US 4 679 379, US 2015/329230 and US 2008/209866.

[0006] In practice, the machine forms the wrapper from a flat strip of film of wrapping material (fed from a reel located below a plane of movement of the groups of products) and which, by means of special folding elements (called folding ties), is progressively folded back on itself in such a way as to generate a tubular shape, supported from the inside of the wrapper being formed by suitable supporting elements or walls (so as to define a "tunnel" with a quadrangular cross section), and having longitudinal flaps positioned next to and superposed on each other along the upper surface of the tunnel.

[0007] There are, moreover, the first sealing elements located at the front of the wrapper and the folding elements, oriented transversely to the tubular shape, which then allow the wrapper to be sealed, transversally, in such a way as to form, in sequence, a closed front end and rear end.

[0008] Lastly, second sealing elements, oriented longitudinally to the wrapper and facing the above-mentioned longitudinal flaps, close the tubular wrapper longitudinally in such a way as to completely close the wrapping. Basically, the process for forming the wrapping on the groups of products comprises the following steps:

• forming the wrapping with the film around the above-mentioned folding elements and the supporting elements or walls;
• first head sealing of the wrapping film;
• inserting into the channel formed by the four walls of the folders a predetermined number of groups of products, until making contact with the closed front end of the wrapper;
• further feeding of the groups of products beyond the above-mentioned transversal sealing elements, with simultaneous feeding of the film from the reel thanks to the pushing of the products, and relative forming of the wrapping, as the front closed end feeds along the machine with the products introduced;
• at the same time as forming the wrapping, longitudinal sealing of the above-mentioned superposed flaps of film occurs using the above-mentioned second sealing elements;
• further activation of the first transversal sealing elements designed to close the wrapper behind the products already bagged;
• separating cut of the bag thus obtained from the rest of the film, using cutting elements, thus starting a new and subsequent cycle for bagging the groups of products.

[0009] However, this machine and the relative method have several drawbacks. A first drawback is due to the fact that the structure of the frame defining the channel for the groups of products determines a separation between wrapping film (wound around the frame) and the products and, consequently, the package is often obtained with slack or "loose" side walls with reduced rigidity of the pack and greater difficulty in the subsequent storage.

[0010] Another drawback is due to the fact that actual feeding of the film is accomplished through the pushing of the group of products on the sealing head and, consequently, to prevent breakage of the bottom/top of the bag it is necessary to reduce the machine cycle time to guarantee a perfect sealing of the flaps which form the bottom/top.

[0011] In addition, there is the fact that the market to which this machine is directed requires the further specifications that the machine structured as described above cannot meet.

[0012] One of these relates to the possibility of modifying, that is to say, reducing, the overall size of the group of products.

[0013] The other need is given by the reduced flexibility of the machine due to the difficult and laborious modification of the size of the tunnel during format changeover which, often, requires the complete change of the supporting walls and, in some cases, even of the folders or ties.

Disclosure of the invention

[0014] The aim of this invention is to provide a method and a machine for making a package for groups of products for sanitary use which overcomes the above-mentioned disadvantages of the prior art.

[0015] More specifically, the aim of this invention is to provide a method and a machine for making a package of groups of products for sanitary use which are able to modify, during the wrapping cycle step, the overall size, by reducing, the group of products.

[0016] A further aim of this invention is to provide a method and a machine for making a package for groups of products for sanitary use with high operational flexibility without modifying the basic structure of the machine. These aims are fully achieved by the method and by the machine for making a package for groups of products for sanitary use according to the invention, as characterised in the appended claims.

Brief description of drawings

[0017] Further features of the invention will become more apparent from the following detailed description of a preferred, non-limiting embodiment of it, illustrated by way of example in the accompanying drawings, in which:

• Figure 1 illustrates schematic perspective top view of a machine for making a package of groups of products for sanitary use, according to this invention, and implementing the method for forming the package of groups of products;
• Figure 2 illustrates a rear view, with some parts cut away, of the machine of Figure 1;
• Figure 3 illustrates a perspective view, with some parts cut away, of the load-bearing frame of the machine of the previous drawings;
• Figure 4 illustrates a rear view of a diagram of the main parts of the machine of the previous drawings;
• Figure 5 illustrates a rear view of the machine of the previous drawings showing the anti-bending contrast elements.

Detailed description of preferred embodiments of the invention

[0018] With reference to the accompanying drawings, and in particular Figure 1, the method and the machine according to the invention are used for making a package for groups of products for sanitary use, such as, but without restricting the scope of the invention, rolls of "tissue" products such as, for example, rolls of paper for sanitary and/or household use or unwoven products such as nappies.

[0019] More specifically, the machine according to the invention (and the relative method) is a bagging machine which is used for wrapping a certain number of groups of products already packaged using plastic film or for bagging of groups of products formed by batches of loose products.

[0020] The method for making a package 1 of groups 2 of products for sanitary use comprises at least the following steps:

• a forming of a length of tubular film by means of continuous film 3 around a frame 4 comprising elements 5 for folding the film 3 and a plurality of walls 6, 7 forming a tubular channel 8 for the passage of the groups 2 of products; the tubular channel 8 has a width L and a height H;
• a first join, wherein head flaps of the film 3 are joined to form a head end, using first transversal joining elements 9 positioned close to the front end of the frame 4 relative to a feed direction A of the groups 2 of products;
• inserting in the tubular channel 8, in the feed direction A and using a pushing unit 10, a predefined number of groups 2 of products, advancing until close to the closed head end of the film 3 to form a first portion of the package 1;
• further feeding of the groups 2 of products beyond the first joining elements 9, with simultaneous feeding of the film 3 and relative forming of a further portion of the package 1 beyond the frame 4;
• a second join, wherein the longitudinal superposed flaps of the film 3 are joined by second longitudinal joining elements 11, simultaneously with the further feeding step;
• a third join, wherein the tail flaps of the film 3 are joined, using the first transversal joining elements 9, in order to close the package 1 at the rear of the groups 2 of products bagged.

[0021] As illustrated (see Figures 2 to 5) at least between the step of introducing the groups 2 of products in the tubular channel 8 and the step of further feeding the groups 2 of products beyond the first transversal joining elements 9 there is a step of modifying (temporary) the size of the tubular channel 8 using a movement device 12 for moving the frame 4 in such a way as to reduce the cross section of the tubular channel 8 and obtain a reduction in the overall size of the groups 2 of products by flattening them. In other words, the groups 2 of products inserted in the tubular channel 8 undergo a flattening which is able (at least temporarily) to reduce their size (preferably, as described below, in terms of width).

[0022] This allows, together with an adaptation of the film 3 (as described in more detail below), the final package 1 to be made which is extremely compact and stable, also with a saving in the quantity of film used.

[0023] Preferably, the step of modifying the size of the tubular channel 8 is given by the reduction in the width L of the channel 8.

[0024] Preferably, the step of modifying the size of the tubular channel 8 is given by the reduction in the width L of the channel 8 and occurs with the groups 2 of products completely housed in the tubular channel 8 and feeding along the tubular channel 8.

[0025] In short, the step of reducing the width L of the channel 8 may be of the dynamic type (movement of side walls 7 of the channel 8 simultaneously with the sliding movement of the groups 2 of products): thanks to these type of steps, the machine cycle times remain substantially unaltered. Alternatively, the step of modifying the size of the tubular channel 8 is again given by the reduction in the width L and occurs with the groups 2 of products completely housed in the tubular channel 8 and stationary inside the tubular channel 8, whilst the side walls 7 move.

[0026] In this case, the step of reducing the width L of the channel 8 may be of the static type (movement of the walls 6 of the channel 8 with groups 2 of products provisionally stationary): this type of choice might be useful if it is necessary to wait a few seconds to allow a correct adhesion in the joining of the tail flaps of the package previously obtained.

[0027] Preferably, the step of modifying the width of the tubular channel 8 occurs by a movement step, which is translational and towards each other, of at least two side walls 7 of the frame 4 forming the tubular channel 8.

[0028] In light of this, the step of modifying the width L of the tubular channel 8 also occurs by a movement step (which is translational and towards each other) of the folding elements 5 in such a way as to adapt also the extension of the film 3 around the frame 4 to the different perimeter dimension reached by the tubular channel 8.

[0029] It should be noted that, after the third step of joining the tail flaps of the film 3 there is a step of restoring the previous size (width L) of the tubular channel 8.

[0030] In this way, the next cycle starts again with the dimensions of the tubular channel 8 decided on the size of the groups 2 of products decided originally.

[0031] This invention, as mentioned, also provides a machine, labelled 100 in its entirety, for making a package 1 of groups 2 of products for sanitary use. The machine 100 comprises a station 13 for feeding a continuous wrapping film 3 (for example a roll of film).

[0032] The machine 100 also comprises a frame 4 for forming a tubular length of the continuous film 3.

[0033] The frame 4 has folding elements 5 and a plurality of walls 6, 7 forming a tubular channel 8 for the passage of the groups 2 of products and on which the continuous film 3 is wound.

[0034] The tubular channel 8 has a width L and a height H.

[0035] The machine 100 also comprises a pushing unit 10 for moving a predetermined number of groups 2 of products inside the tubular channel 8 in a feed direction A.

[0036] Moreover, the machine 100 has first transversal joining elements 9 located downstream of the frame 4, relative to the feed direction A, and designed to join, respectively, the head flaps of the film 3, prior to the arrival of the groups 2 of products, and the tail flaps of the film 3 after the passage of the groups 2 of products wrapped in film 3 beyond the first transversal joining elements 9.

[0037] The machine 100 also comprises second longitudinal joining elements 11 located close to the frame 4 (above the latter), and designed to join two longitudinal superposed flaps of the film 1 at the formation of the package 1.

[0038] As illustrated, the machine 100 comprises at least two of the walls 6, 7 forming the channel 8 movable towards and away from each another by a movement device 12 connected to the frame 4, so as to allow the modification, at least temporarily, of the size of the tubular channel 8 in order to reduce the cross section of the tubular channel 8 during the passage of the groups 2 of products and to obtain a reduction in the overall size of the groups 2 of products by flattening them.

[0039] It should be noted that the tubular channel 8 may be formed by a set of separate walls (lower, upper and side) to form the channel 8, or by two individual C-shaped profiles facing each other (configuration not illustrated), or, also, by four corner segments which make up the bottom and top walls 6 and the side walls 7 (see Figures 4 and 5).

[0040] The folding elements 5 are formed by two pairs of flaps 5a and 5b positioned on both sides of the tubular channel 8 and by a pair of intersecting plates 5c positioned above the tubular channel 8 for guiding and retaining the superposed free flaps of the film 3 before they are joined with the second longitudinal joining elements 11.

[0041] It should be noted that the first transversal joining elements 9 comprise two sealing bars positioned beyond the outlet of the tubular channel 8 combined with a knife (not illustrated) for the separation of the completed package 1 from the subsequent package being formed.

[0042] The second longitudinal joining elements 11 comprise a sealing head configured to hot seal the superposed flaps of the film 3.

[0043] Preferably, the movement device 12 comprises at least a first shaft 14 with motor-driven screw and rotatably connected to a pair of vertical supporting arms 15 associated with the side walls 7 of the frame 4 (see Figures 2 to 5).

[0044] The first screw shaft 14 is configured for moving, in both directions, the pair of arms 15 so as to allow a movement towards and away from each other, thereby obtaining a variation, even temporary, of the width L of the tubular channel 8.

[0045] In light of this, the first screw shaft 14 has two threads in opposite directions, separate from each other to allow, during its rotation (in either direction), the movement towards or away from each other of the arms 15. Preferably, the device 12 comprises a second shaft 16 with a motor-driven screw positioned parallel to the first screw shaft 14 which is motor-driven and rotatably connected to vertical arms 17 supporting the folding elements 5.

[0046] In light of this, the second screw shaft 16 is configured for moving, in both directions, the vertical supporting arms 17 so as to allow a movement towards and away from each other, thereby obtaining a variation, even temporary, of the dimensions of the folding elements 5.

[0047] The modification of the folding elements 5 is correlated with the modification of the width L of the tubular channel 8 in such a way as to adapt the superposed flaps of the film 3 to the new size.

[0048] It should be noted that the first 14 and the second 16 screw shaft are connected to a single drive unit M (for example by means of transmission belts).

[0049] Alternatively, the two screw shafts 14 and 16 may be connected to independent drive units.

[0050] The machine 100 comprises the sensors 18 for detecting the compressive force connected at least to the first screw shaft 14 (but they might also be connected to the second screw shaft 16) and configured to send a corresponding signal relating to the compressive force value to a control unit 19 connected to the drive unit(s) M.

[0051] According to an embodiment (see Figure 4), but without limiting the scope of the invention, the detection sensors 18 may be of the load cell type interposed between the first arms 15 and the side walls 7 in such a way as to check the compressive force imparted by the first arms 15 on the side walls 7.

[0052] In light of this, the control unit 19 is programmed for turning ON or OFF the drive unit(s) M for moving the side walls 7 and the folding elements 5 by a stroke equivalent to a compression value between a minimum and a maximum stroke range, as a function of a plurality of parameters preset in the control unit 19 and the detection signal sent by the detection sensors 18.

[0053] In other words, the control unit 19 has memory banks in which are set the predetermined minimum and maximum compression values and calculated as a function, for example, a series of parameters, starting from the type of final format of the package to be obtained:

• type of product (roll or nappy, for example);
• package softness defined, for example, by the density of the product (roll or nappy, for example);
• configuration of the pack or bag to be formed (in the case of groups of packages side by side or groups of loose products).

[0054] Based on these parameters, therefore, there will be different thresholds (minimum and maximum stroke).

[0055] The activation of the motor(s) M determines the start of the compression stroke and, when the compression value recorded by the sensors 18 enters the desired threshold (ranging between the minimum and a maximum values), the unit 19 may already stop the motor(s) M. Obviously, the compression may be increased, upon the decision of the operator, but only until reaching the maximum set value.

[0056] The machine 100 also comprises dynamic contact elements 20 associated with the folding elements 5 and positioned outside and at a predetermined distance from the two side walls 7 of the frame 4 (see Figure 5).

[0057] In light of this, the dynamic contact elements 20 are configured to oppose, if necessary, a deformation, towards the outside, of the side walls 7 of the frame 4.

[0058] The dynamic contact elements 20 have the capacity, once in contact with the corresponding side wall 7, to make a counter push on the wall itself, but at the same time to avoid any block on the feed movement of the wrapping film 3.

[0059] As illustrated in Figure 5, these contact elements 20 may consist of rollers which can turn idly and are connected (by means of supporting shafts) to the folding elements 5.

[0060] The rollers 20 are arranged a few millimetres away from the corresponding side wall 7 and they adapt to the movement of the side walls 7 thanks to the translation of the folding elements 5.

[0061] If there is a bending of the side walls 7 due to their compression, the rollers 20 are designed to oppose this movement towards the outside, maintaining the parallelism of the walls 7 and their position in compression. Moreover, since the rollers 20 can rotate freely, they do not oppose the feed movement of the film 3 during the step of packaging the groups 2 of products.

[0062] As an alternative to the rollers 20 there may be motor-driven belts (not illustrated) looped on pairs of pulleys and again supported by the folding elements 5.

[0063] Also in this case, if a branch of the belt is resting on the walls, it allows the film 3 to feed along the side walls 7 during the step of packaging groups 1 of products.

[0064] Thanks to this packaging method and the respective packaging machine the preset aims are achieved.

[0065] Thanks to the "on time" controlled compression system, the groups of products are reduced in size in terms of width in a short time and without excessively altering the machine structure.

[0066] Together with the compression there is, simultaneously, an adaptation of the extension of film so as to make the final package extremely compact and stable, also with a saving in the quantity of film used.

Claims

1. A method for making a package (1) of groups (2) of products for sanitary use, the method comprising at least the following steps:

- forming a length of tubular film by means of continuous film (3) around a frame (4) comprising elements (5) for folding the film (3) and a plurality of walls (6, 7) forming a tubular channel (8) for the passage of the groups (2) of products; the tubular channel (8) having at least a width (L) and a height (H);

- a first join, wherein head flaps of the film (3) are joined to form a head end, using first transversal joining elements (9) positioned close to the front end of the frame (4) relative to a feed direction (A) of the groups (2) of products;

- inserting in the tubular channel (8), in the feed direction (A) and using a pushing unit (10), a predefined number of groups (2) of products, advancing until close to the closed head end of the film (3) to form a first portion of the package (1);

- further feeding of the groups (2) of products beyond the first joining elements (9), with simultaneous feeding of the film (3) and relative forming of a further portion of the package (1) beyond the frame (4);

- a second join, wherein the longitudinal superposed flaps of the film (3) are joined by second longitudinal joining elements (11), simultaneously with the further feeding step;

- a third join, wherein the tail flaps of the film (3) are joined, using the first transversal joining elements (9), in order to close the package (1) at the rear of the groups (2) of products bagged;
characterised in that it comprises, at least between the step of introducing the groups (2) of products in the tubular channel (8) and the step of further feeding the groups (2) of products beyond the first transversal joining elements (9), a step of modifying the size of the tubular channel (8) using a movement device (12) for moving the frame (4) in such a way as to reduce a cross section of the tubular channel (8) and obtain a reduction in the overall size of the groups (2) of products by flattening them.

2. The method according to claim 1, wherein the step of modifying the size of the tubular channel (8) is given by the reduction in the width (L) of the channel (8) and occurs with the groups (2) of products completely housed in the tubular channel (8) and feeding along the tubular channel (8).

3. The method according to claim 1, wherein the step of modifying the size of the tubular channel (8) is given by the reduction in the width (L) of the channel (8) and occurs with the groups (2) of products completely housed in the tubular channel (8) and stationary inside the tubular channel (8).

4. The method according to any one of the preceding claims, wherein the step of modifying the size of the tubular channel (8) occurs by a movement step, which is translational and towards each other, of at least two side walls (7) of the frame (4) forming the tubular channel (8).

5. The method according to any one of claims 1 to 3, wherein the step of modifying the size of the tubular channel (8) occurs by a movement step, which is translational and towards each other, of at least two side walls (7) of the frame (4) forming the tubular channel (8) and of the folding elements (5) in such a way as to adapt also the extension of the film (3) around the frame (4) to the different perimeter dimension reached by the tubular channel (8).

6. The method according to any one of the preceding claims, wherein after the third step of joining the tail flaps of the film (3) there is a step of restoring the previous size of the tubular channel (8).

7. A machine for making a package (1) of groups (2) of products for sanitary use, comprising at least:

- a station (13) for feeding a continuous wrapping film (3);

- a frame (4) for forming a tubular length of the film (3); the frame (4) having folding elements (5) and a plurality of walls (6, 7) forming a tubular channel (8) for the passage of the groups (2) of products and on which the continuous film (3) is wound; the tubular channel (8) having at least a width (L) and a height (H);

- a pushing unit (10) for moving a predetermined number of groups (2) of products inside the tubular channel (8) in a feed direction (A);

- first transversal joining elements (9) located downstream of the frame (4), relative to the feed direction (A), and designed to join, respectively, the head flaps of the film (3), prior to the arrival of the groups (2) of products, and the tail flaps of the film (3) after the passage of the groups (2) of products wrapped in film (3) beyond the first transversal joining elements (9);

- second longitudinal joining elements (11) located close to the frame (4), and designed to join two longitudinal superposed flaps of the film (3) at the formation of the package (1),

- at least two of the walls (6, 7) forming the channel (8) movable towards and away from each another by a movement device (12) connected to the frame (4) so as to allow the modification, at least temporarily, of the size of the tubular channel (8) during the passage of the groups (2) of products and to obtain a reduction in the overall size of the groups (2) of products by flattening them;

characterised in that it comprises:

- dynamic contact elements (20) associated with the folding elements (5) and positioned outside and at a predetermined distance from the two walls (7) of the frame (4) movable towards and away from each another; the dynamic contact elements (20) being configured to oppose, if necessary, a deformation, towards the outside, of the two walls (7) of the frame (4) so as to allow the parallelism between the two walls (7) and the feeding of the wrapping film (3) to be maintained.

8. The machine according to claim 7, wherein the movement device (12) comprises at least a first screw shaft (14) with motor-driven and rotatably connected to a pair of vertical supporting arms (15) associated with the side walls (7) of the frame (4); the first screw shaft (14) being configured for moving, in both directions, the pair of arms (15) so as to allow a movement towards and away from each other, thereby obtaining a variation, even temporary, of the width (L) of the tubular channel (8).

9. The machine according to claim 8, wherein the movement device (12) comprises a second screw shaft (16) with a motor-driven positioned parallel to the first shaft (14) which is motor-driven and rotatably connected to vertical arms (17) supporting the folding elements (5); the second screw shaft (16) being configured for moving, in both directions, the vertical supporting arms (17) so as to allow a movement towards and away from each other, thereby obtaining a variation, even temporary, of the dimensions of the folding elements (5), correlated with the modification of the width (L) of the tubular channel (8), and in such a way as to adapt the superposed flaps of the film (3) to the new size.

10. The machine according to claim 8 or 9, wherein the first (14) and the second (16) screw shaft are connected to a single drive unit (M).

11. The machine according to any one of claims 8 to 10, comprising sensors (18) for detecting the compressive force connected at least to the first screw shaft (14) and configured for sending a corresponding signal relating to a compressive force value to a control unit (19) connected to the drive unit (M).

12. The machine according to claim 11, wherein the control unit (19) is programmed for turning ON or OFF the drive unit (M) for moving the side walls (7) and the folding elements (5) by a stroke equivalent to a compression value between a minimum and a maximum stroke range, as a function of a plurality of parameters preset in the control unit (19) and the detection signal sent by the detection sensors (18).

Ansprüche

1. Verfahren zur Herstellung einer Verpackung (1) von Gruppen (2) von Produkten für sanitäre Zwecke, wobei das Verfahren mindestens die folgenden Schritte umfasst:

- Bilden einer Länge einer rohrförmigen Folie mittels einer durchgehenden Folie (3) um einen Rahmen (4), umfassend Elemente (5) zum Falten der Folie (3) und eine Vielzahl an Wänden (6, 7), die einen rohrförmigen Kanal (8) für den Durchgang der Gruppen (2) von Produkten bilden; wobei der rohrförmige Kanal (8) mindestens eine Breite (L) und eine Höhe (H) aufweist;

- eine erste Zusammenfügung, wobei Kopfklappen der Folie (3) zusammengefügt werden, um ein Kopfende unter Verwendung erster Querzusammenfügungselemente (9) zu bilden, die nahe dem vorderen Ende des Rahmens (4) relativ zu einer Zuführrichtung (A) der Gruppen (2) von Produkten positioniert sind;

- Einführen einer vordefinierten Anzahl von Gruppen (2) von Produkten in den rohrförmigen Kanal (8) in der Zuführrichtung (A) und unter Verwendung einer Schiebeeinheit (10) und deren Vorschieben bis nahe dem geschlossenen Kopfende der Folie (3), um einen ersten Abschnitt der Verpackung (1) zu bilden;

- weiteres Zuführen der Gruppen (2) von Produkten über die ersten Zusammenfügungselemente (9) hinaus bei gleichzeitigem Zuführen der Folie (3) und relativer Bildung eines weiteren Abschnitts der Verpackung (1) über den Rahmen (4) hinaus;

- eine zweite Zusammenfügung, wobei die in Längsrichtung überlagerten Klappen der Folie (3) gleichzeitig mit dem weiteren Zuführungsschritt durch zweite Längszusammenfügungselemente (11) zusammengefügt werden;

- eine dritte Zusammenfügung, wobei die Endklappen der Folie (3) unter Verwendung der ersten Querzusammenfügungselemente (9) zusammengefügt werden, um die Verpackung (1) an der Rückseite der Gruppen (2) der eingepackten Produkte zu schließen;
dadurch gekennzeichnet, dass es zumindest zwischen dem Schritt zum Einführen der Gruppen (2) von Produkten in den rohrförmigen Kanal (8) und dem Schritt zum weiteren Zuführen der Gruppen (2) von Produkten über die ersten Querzusammenfügungselemente (9) hinaus einen Schritt zum Modifizieren der Größe des rohrförmigen Kanals (8) unter Verwendung einer Bewegungsvorrichtung (12) zum Bewegen des Rahmens (4) umfasst, so dass ein Querschnitt des rohrförmigen Kanals (8) reduziert wird und eine Reduzierung der Gesamtgröße der Gruppen (2) von Produkten durch Abflachen erhalten wird.

2. Verfahren nach Anspruch 1, wobei der Schritt zum Modifizieren der Größe des rohrförmigen Kanals (8) durch die Reduzierung der Breite (L) des Kanals (8) gegeben ist und bei den Gruppen (2) von Produkten stattfindet, die im rohrförmigen Kanal (8) vollständig untergebracht sind und entlang des rohrförmigen Kanals (8) zugeführt werden.

3. Verfahren nach Anspruch 1, wobei der Schritt zum Modifizieren der Größe des rohrförmigen Kanals (8) durch die Reduzierung der Breite (L) des Kanals (8) gegeben ist und bei den Gruppen (2) von Produkten stattfindet, die im rohrförmigen Kanal (8) vollständig untergebracht und stationär im rohrförmigen Kanal (8) sind.

4. Verfahren nach einem der vorhergehenden Ansprüche, wobei der Schritt zum Modifizieren der Größe des rohrförmigen Kanals (8) durch einen Bewegungsschritt, der translatorisch und aufeinander hinführend ist, von mindestens zwei Seitenwänden (7) des Rahmens (4), der den rohrförmigen Kanal (8) bildet, stattfindet.

5. Verfahren nach einem der Ansprüche 1 bis 3, wobei der Schritt zum Modifizieren der Größe des rohrförmigen Kanals (8) durch einen Bewegungsschritt, der translatorisch und aufeinander hinführend ist, von mindestens zwei Seitenwänden (7) des Rahmens (4), der den rohrförmigen Kanal (8) bildet, und der Faltelemente (5) stattfindet, so dass auch die Ausdehnung der Folie (3) um den Rahmen (4) an die unterschiedliche Umfangsabmessung, die durch den rohrförmigen Kanal (8) erreicht wird, angepasst wird.

6. Verfahren nach einem der vorhergehenden Ansprüche, wobei nach dem dritten Schritt zum Zusammenfügen der Endklappen der Folie (3) ein Schritt zum Wiederherstellen der vorherigen Größe des rohrförmigen Kanals (8) stattfindet.

7. Maschine zur Herstellung einer Verpackung (1) von Gruppen (2) von Produkten für sanitäre Zwecke, umfassend mindestens:

- eine Station (13) zum Zuführen einer durchgehenden Umhüllungsfolie (3);

- einen Rahmen (4) zum Bilden einer rohrförmigen Länge der Folie (3); wobei der Rahmen (4) Faltelemente (5) und eine Vielzahl an Wänden (6, 7) aufweist, die einen rohrförmigen Kanal (8) für den Durchgang der Gruppen (2) von Produkten bilden und auf denen die durchgehende Folie (3) umhüllt wird; wobei der rohrförmige Kanal (8) mindestens eine Breite (L) und eine Höhe (H) aufweist;

- eine Schiebeeinheit (10) zum Bewegen einer vorbestimmten Anzahl von Gruppen (2) von Produkten innerhalb des rohrförmigen Kanals (8) in einer Zuführrichtung (A);

- erste Querzusammenfügungselemente (9), die sich stromabwärts des Rahmens (4) relativ zur Zuführrichtung (A) befinden und so ausgelegt sind, dass sie die Kopfklappen der Folie (3) vor dem Eintreffen der Gruppen (2) von Produkten zusammenfügen und die Endklappen der Folie (3) nach dem Durchgang der Gruppen (2) von in Folie (3) umhüllten Produkten über die ersten Querzusammenfügungselemente (9) hinaus zusammenfügen;

- zweite Längszusammenfügungselemente (11), die sich nahe dem Rahmen (4) befinden und so ausgelegt sind, dass sie bei der Bildung der Verpackung (1) zwei in Längsrichtung überlagerten Klappen der Folie (3) zusammenfügen;

- mindestens zwei der Wände (6, 7), die den Kanal (8) bilden, durch eine mit dem Rahmen (4) verbundene Bewegungsvorrichtung (12) aufeinander zu und voneinander weg bewegbar sind, um die Modifikation, zumindest vorübergehend, der Größe des rohrförmigen Kanals (8) während des Durchgangs der Gruppen (2) von Produkten zu ermöglichen und um eine Reduzierung der Gesamtgröße der der Gruppen (2) von Produkten durch Abflachen zu erreichen;

dadurch gekennzeichnet, dass es umfasst:

- dynamische Kontaktelemente (20), die mit den Faltelementen (5) assoziiert sind und außen und in einem vorbestimmten Abstand von den zwei Wänden (7) des Rahmens (4) positioniert sind, die aufeinander zu und voneinander weg bewegbar sind; wobei die dynamischen Kontaktelemente (20) so konfiguriert sind, dass sie erforderlichenfalls einer Verformung der beiden Wände (7) des Rahmens (4) nach außen entgegenwirken, um zu ermöglichen, dass die Parallelität zwischen den beiden Wänden (7) und die Zuführung der Umhüllungsfolie (3) beibehalten wird.

8. Maschine nach Anspruch 7, wobei die Bewegungsvorrichtung (12) mindestens eine erste Schneckenwelle (14) umfasst, motorgetrieben und drehbar mit einem Paar vertikaler Stützarme (15) verbunden, die mit den Seitenwänden (7) des Rahmens (4) assoziiert sind; wobei die erste Schneckenwelle (14) konfiguriert ist, um das Paar von Armen (15) in beide Richtungen zu bewegen, um eine Bewegung aufeinander zu und voneinander weg zu ermöglichen, wodurch eine, sogar vorübergehende, Variation der Breite (L) des rohrförmigen Kanals (8) erhalten wird.

9. Maschine nach Anspruch 8, wobei die Bewegungsvorrichtung (12) eine zweite Schneckenwelle (16) mit einem Motorantrieb umfasst, der parallel zur ersten Welle (14) positioniert ist, die motorgetrieben ist und drehbar mit vertikalen Armen (17) verbunden ist, die die Faltelemente (5) abstützen; wobei die zweite Schneckenwelle (16) so konfiguriert ist, dass sie die vertikalen Stützarme (17) in beide Richtungen bewegt, um eine Bewegung aufeinander zu und voneinander weg zu ermöglichen, wodurch eine, sogar vorübergehende, Variation der Abmessungen der Faltelemente (5) erhalten wird, die mit der Modifikation der Breite (L) des rohrförmigen Kanals (8) korreliert sind, und so dass die überlagerten Klappen der Folie (3) an die neue Größe angepasst werden.

10. Maschine nach Anspruch 8 oder 9, wobei die erste (14) und die zweite (16) Schneckenwelle mit einer einzelnen Antriebseinheit (M) verbunden sind.

11. Maschine nach einem der Ansprüche 8 bis 10, umfassend Sensoren (18) zum Erfassen der Druckkraft, die mindestens mit der ersten Schneckenwelle (14) verbunden ist und konfiguriert zum Senden eines entsprechenden Signals bezüglich eines Druckkraftwerts an eine Steuereinheit (19), die mit der Antriebseinheit (M) verbunden ist.

12. Maschine nach Anspruch 11, wobei die Steuereinheit (19) zum Ein- oder Ausschalten der Antriebseinheit (M) zum Bewegen der Seitenwände (7) und der Faltelemente (5) um einen Hub programmiert ist, der einem Kompressionswert zwischen einem minimalen und einem maximalen Hubbereich als eine Funktion einer Vielzahl an in der Steuereinheit (19) voreingestellten Parametern und dem von den Erfassungssensoren (18) gesendeten Erfassungssignal entspricht.

Revendications

1. Procédé de fabrication d'un emballage (1) de groupes (2) de produits à usage sanitaire, le procédé comprenant au moins les étapes suivantes :

- former une longueur de film tubulaire au moyen d'un film continu (3) autour d'un cadre (4) comprenant des éléments (5) servant à plier le film (3) et une pluralité de parois (6, 7) formant un canal tubulaire (8) pour le passage des groupes (2) de produits ; le canal tubulaire (8) ayant au moins une largeur (L) et une hauteur (H) ;

- une première jonction, dans laquelle les rabats de tête du film (3) sont joints pour former une extrémité de tête, en utilisant des premiers éléments de jonction (9) transversaux positionnés près de l'extrémité avant du cadre (4) par rapport à une direction d'alimentation (A) des groupes (2) de produits ;

- introduire dans le canal tubulaire (8), dans la direction d'alimentation (A) et à l'aide d'une unité de poussée (10), un nombre prédéfini de groupes (2) de produits, en avançant jusqu'à proximité de l'extrémité de tête fermée du film (3) pour former une première partie de l'emballage (1) ;

- continuer à alimenter les groupes (2) de produits au-delà des premiers éléments de jonction (9), avec l'alimentation simultanée du film (3) et la formation relative d'une partie supplémentaire de l'emballage (1) au-delà du cadre (4) ;

- une seconde jonction, dans laquelle les rabats longitudinaux superposés du film (3) sont joints par des seconds éléments de jonction longitudinaux (11), simultanément avec l'étape d'alimentation supplémentaire ;

- une troisième jonction, dans laquelle les rabats arrière du film (3) sont joints, en utilisant les premiers éléments de jonction transversaux (9), afin de fermer l'emballage (1) à l'arrière des groupes (2) de produits ensachés ;
caractérisé en ce qu'il comprend, au moins entre l'étape d'introduction des groupes (2) de produits dans le canal tubulaire (8) et l'étape d'alimentation supplémentaire des groupes (2) de produits au-delà des premiers éléments de jonction transversaux (9), une étape consistant à modifier la taille du canal tubulaire (8) en utilisant un dispositif de déplacement (12) servant à déplacer le cadre (4) de manière à réduire une section transversale du canal tubulaire (8) et à obtenir une réduction de la taille globale des groupes (2) de produits en les aplatissant.

2. Procédé selon la revendication 1, dans lequel l'étape consistant à modifier la taille du canal tubulaire (8) est donnée par la réduction de la largeur (L) du canal (8) et se produit avec les groupes (2) de produits complètement logés dans le canal tubulaire (8) et avançant le long du canal tubulaire (8).

3. Procédé selon la revendication 1, dans lequel l'étape consistant à modifier la taille du canal tubulaire (8) est donnée par la réduction de la largeur (L) du canal (8) et se produit avec les groupes (2) de produits complètement logés dans le canal tubulaire (8) et stationnaires à l'intérieur du canal tubulaire (8).

4. Procédé selon l'une quelconque des revendications précédentes, dans lequel l'étape consistant à modifier la taille du canal tubulaire (8) se produit par une étape de déplacement, étant en translation et en approche réciproque, d'au moins deux parois latérales (7) du cadre (4) formant le canal tubulaire (8).

5. Procédé selon l'une quelconque des revendications 1 à 3, dans lequel l'étape consistant à modifier la taille du canal tubulaire (8) se produit par une étape de déplacement, étant en translation et en approche réciproque, d'au moins deux parois latérales (7) du cadre (4) formant le canal tubulaire (8) et des éléments de pliage (5) de manière à adapter également l'extension du film (3) autour du cadre (4) à la dimension de périmètre différente atteinte par le canal tubulaire (8).

6. Procédé selon l'une quelconque des revendications précédentes, dans lequel, après la troisième étape de jonction des rabats arrière du film (3), il est prévu une étape de rétablissement de la dimension précédente du canal tubulaire (8).

7. Machine de fabrication d'un emballage (1) de groupes (2) de produits à usage sanitaire, comprenant au moins :

- un poste (13) d'alimentation d'un film d'emballage continu (3) ;

- un cadre (4) servant à former une longueur tubulaire du film (3) ; le cadre (4) comportant des éléments de pliage (5) et une pluralité de parois (6, 7) formant un canal tubulaire (8) pour le passage des groupes (2) de produits et sur lequel le film continu (3) est enroulé ; le canal tubulaire (8) ayant au moins une largeur (L) et une hauteur (H) ;

- une unité de poussée (10) servant à déplacer un nombre prédéterminé de groupes (2) de produits à l'intérieur du canal tubulaire (8) dans une direction d'alimentation (A) ;

- des premiers éléments de jonction transversaux (9) situés en aval du cadre (4), par rapport à la direction d'alimentation (A), et destinés à joindre, respectivement, les rabats de tête du film (3), avant l'arrivée des groupes (2) de produits, et les rabats arrière du film (3) après le passage des groupes (2) de produits enveloppés dans le film (3) au-delà des premiers éléments de jonction transversaux (9) ;

- des seconds éléments de jonction longitudinaux (11) situés à proximité du cadre (4), et destinés à relier deux rabats longitudinaux superposés du film (3) lors de la formation de l'emballage (1),

- au moins deux des parois (6, 7) formant le canal (8) pouvant être rapprochées et éloignées l'une de l'autre par un dispositif de déplacement (12) relié au cadre (4) de manière à permettre la modification, au moins temporairement, de la taille du canal tubulaire (8) pendant le passage des groupes (2) de produits et à obtenir une réduction de la taille globale des groupes (2) de produits en les aplatissant ;

caractérisée en ce qu'elle comprend :

- des éléments de contact dynamiques (20) associés aux éléments de pliage (5) et positionnés à l'extérieur et à une distance prédéterminée des deux parois (7) du cadre (4) pouvant se rapprocher et s'éloigner l'une de l'autre ; les éléments de contact dynamiques (20) étant configurés pour s'opposer, si nécessaire, à une déformation, vers l'extérieur, des deux parois (7) du cadre (4) de manière à permettre le maintien du parallélisme entre les deux parois (7) et l'alimentation du film d'emballage (3).

8. Machine selon la revendication 7, dans laquelle le dispositif de déplacement (12) comprend au moins un premier arbre à vis (14) motorisé et relié en rotation à une paire de bras de support verticaux (15) associés aux parois latérales (7) du cadre (4) ; le premier arbre à vis (14) étant configuré pour déplacer, dans les deux directions, la paire de bras (15) de manière à permettre un mouvement de rapprochement et d'éloignement réciproque, obtenant ainsi une variation, même temporaire, de la largeur (L) du canal tubulaire (8).

9. Machine selon la revendication 8, dans laquelle le dispositif de déplacement (12) comprend un deuxième arbre à vis (16) motorisé positionné parallèlement au premier arbre (14) étant motorisé et relié en rotation à des bras verticaux (17) supportant les éléments de pliage (5) ; le deuxième arbre à vis (16) étant configuré pour déplacer, dans les deux directions, les bras de support verticaux (17) de manière à permettre un mouvement de rapprochement et d'éloignement réciproque, obtenant ainsi une variation, même temporaire, des dimensions des éléments de pliage (5), corrélée à la modification de la largeur (L) du canal tubulaire (8), et de manière à adapter les rabats superposés du film (3) à la nouvelle dimension.

10. Machine selon la revendication 8 ou 9, dans laquelle le premier (14) et le second (16) arbre à vis sont reliés à une seule unité d'entraînement (M).

11. Machine selon l'une quelconque des revendications 8 à 10, comprenant des capteurs (18), servant à détecter la force de compression, reliés au moins au premier arbre de vis (14) et configurés pour envoyer un signal correspondant relatif à une valeur de force de compression à une unité de commande (19) reliée à l'unité d'entraînement (M).

12. Machine selon la revendication 11, dans laquelle l'unité de commande (19) est programmée pour mettre en marche ou arrêter l'unité d'entraînement (M) pour déplacer les parois latérales (7) et les éléments de pliage (5) par une course équivalente à une valeur de compression comprise entre une plage de course minimale et une plage de course maximale, en fonction d'une pluralité de paramètres préréglés dans l'unité de commande (19) et du signal de détection envoyé par les capteurs de détection (18).

Drawing