ES2699448T3 - Procedure and apparatus for gas extraction in packaging - Google Patents

Abstract

A packaging method comprising: providing a semi-sealed package (23) containing a product (20) to be packaged, the semi-sealed package (23) being made from a film (21) and having a sealed first end and a second open end, providing a vacuum chamber (353) that includes a first member (351) and a second member (352) disposed opposite the first member (351), the first member (351) and the second member (351) being 352) relatively movable between a first configuration, in which the first and second members (351, 352) are separated from each other, and a second configuration in which the first and second members (351, 352) are in contact with each other along a perimeter thereof, except for at least one opening (354) that is formed between the first and second members (351, 352), adjust a spacing between the first and second members (351, 352) to carry the first and second members ( 351, 352) to the first configuration, thus opening the vacuum chamber (353), relatively positioning the semi-sealed package (23) and the vacuum chamber (353) such that a terminal part (236) of the second end is located within the vacuum chamber (353) and a non-terminal part (232) of the second end is located outside the vacuum chamber (353), an intermediate portion (234) of the second end passing through the opening ( 354), the intermediate portion (234) extending between the terminal and non-terminal portions (236, 232) of the second end, adjusting the spacing between the first and second members (351, 352) to carry the first and second members (351, 352) to the second configuration, in which second configuration the first and second members (351, 352) are, except for the opening (354), in substantially sealed contact with each other, and the intermediate portion (234) of the second end is received in the opening (354), with the members first and (351, 352), in the second configuration creating, within the vacuum chamber (353), an internal vacuum pressure that is lower than an ambient pressure present in the ambient atmosphere outside the chamber (353) of vacuum, the internal vacuum pressure being selected such that: - a gas flow is determined through the opening (354) which causes the opposite layers of the film (21) at the second end to maintain a substantially separate configuration, and - both the gas inside the semi-sealed package (23) and the gas in the ambient atmosphere are sucked through the opening (354), and a second seal is created in the semi-sealed package (23) in the second end, thus forming a sealed package (24) containing the product (20) and having sealed the first and second ends.

Description

DESCRIPTION

Procedure and apparatus for gas extraction in packaging

Technical field

The present invention relates to a packaging process using a gas extraction station and a packaging apparatus comprising a gas extraction station. The packaging method includes extracting gas from a semi-sealed package or packaging into a gas extraction station having a single vacuum chamber.

Background technique

A packaging apparatus for packaging a food product can be used. The product can be a bare product or a pre-loaded product in a tray. A plastic wrapping tube can be fed continuously through a form apparatus, filling and sealing bags or packages. The film and the product are joined, for example, the product is deposited on the film or the film is wrapped around the product. In some examples, the bare product is fed through a feeding belt. A tube is created around the product by sealing the opposite longitudinal edges of the film. Alternatively, the product is placed in the tube and a leading edge of the package is sealed. Then, the tube is sealed by the trailing edge (at the upstream end) of the package and is cut from the packing tube which is continuously moved.

In some embodiments, the tube can be provided as a tube, or formed from two films or bands longitudinally sealed by two longitudinal edges, or from a single film that folds and seals along its longitudinal edges. In other embodiments, the products are loaded into preformed bags which are then supplied to a gas extraction station and to a sealing station. In addition, some embodiments may facilitate the extraction of gas from two or more packages at the same time in the same process step. The latter can be carried out, for example, by processing two or more bags in the same gas extraction station or by introducing, in parallel, two or more film tubes in a packaging apparatus, in which the tubes are processed in parallel.

Sealing bars can be used to seal the package, of which a lower bar and an upper bar move mutually to contact each other, squeezing the packing material therebetween and providing one or more seals. The sealing rods normally also form an adjacent seal, which comprises the opposite end of the following package, thereby providing a semi-sealed package (eg, with an open end) and a sealed package during a single stage of the packaging process.

Seals are typically regions of packaging material that extend transversely and that have been processed to provide a seal between the interior of the package and the environment. In the context of the present document, whenever reference is made to gas extraction, it is understood that the term "gas" may comprise a particular individual gas or a mixture of gases and, for example, may consist of air (i.e. consist of a mixture of gases corresponding to ambient air). In some embodiments, the packages may be sprayed with a protective gas (sometimes also known as "inert" gas). It is noted that any gas or mixture of known protective gases, for example, CO ^{2 can be used} .

Gas can be injected into the packaging in the space between the product and the film in a loading station with or without a first seal that closes the package by the first end thereof (ie, by a trailing edge). Any remaining gas inside the packaging after gas or air has been removed from it and after the packaging has been sealed ensures a very low residual level of O ² inside the packaging (eg a residual O ^{2 level} of 1). % or lower). This is particularly beneficial with respect to the protection of perishable products (for example, cheese with low level of gasification during ripening).

A packaging device is normally used for many different products in terms of the type of product, size, weight, composition, etc. There is a range of machines with vacuum chamber for an application called "soft vacuum", in which a product (for example, tender or semi-cured cheese with holes) is vacuum-loaded in machines based on a double chamber apparatus. The two chambers are provided with different air pressures and are separated by a dividing wall having a seal. The first chamber is a vacuum chamber, equipped with a vacuum pressure. The second chamber is a chamber placed under vacuum, provided with a vacuum pressure higher than the vacuum pressure provided in the first chamber and contains the product placed in a bag. Generally, such a configuration may involve several limitations. For example, the complexity and cost of the equipment leave room for improvement due to the many components required. In addition, the size of the products that can be processed depends on the size of the second chamber that contains the product during packaging. In some applications, it is difficult to provide cameras of sufficient size due to the structural limitation of some components (for example, the actuators). In addition, maintaining the reliability of the process and the durability of the components can be difficult when the size of the components increases (eg the chambers, the actuators, the seals) since the size usually affects the wear and tear properties. tear In addition, processing times may increase due to the emptying of larger cameras than they take a comparatively longer time.

US 2012/0174531 discloses a packaging machine and a method for forming a vacuum package. A first evacuable chamber is used to house a product housing section of a package therein, while a second evacuable chamber is used to house an opening section of the package therein. Pressure gauges measure the pressure in both chambers, and an air supply valve serves to supply air to the first chamber. The disclosure is characterized in that the air supply valve is a control valve and is adapted to be controlled as a function of the difference between the pressures prevailing in the first and second chambers and which are measured by means of the two pressure gauges. The disclosure also relates to the fact that space is provided in the division between the two chambers and an adjuster is provided to vary and adjust the cross-sectional area of said space.

EP 1564147 describes an apparatus and method for vacuum packing a product in a bag. The apparatus comprises a cover hinged to a base member, the cover and base member being provided with upper and lower partition walls cooperatively defining a first vacuum chamber, a second vacuum chamber adjacent to the first chamber, and a opening that connects the first and second chambers to pass through the neck of the bag. The apparatus further comprises means for evacuating the first and second chambers independently from each other and means for closing the receptacle. The apparatus further comprises means for admitting air into the first vacuum chamber, and the opening is provided with means for reducing the passage of air from one chamber to the other.

An object of the present invention is to provide a packaging method that facilitates the efficient packing of larger products regardless of the size of a vacuum or processing chamber. A further object of the present invention is to provide a packaging method that facilitates the extraction of gas and / or air from a package, similar to the vacuum setting achieved by the known apparatuses and methods, using only one chamber. US4601159 discloses a packaging apparatus having an upper sealing jaw and a lower sealing jaw acting on a tubular film to form a seal in an upstream part of the tubular film and a vacuum plus a seal in a running part down the same tubular film. The documents EP 0836996A1 and US4640081 show the respective packaging procedures with a vacuum station enclosing the packaging to be vacuum-packed.

Summary of the invention

According to the invention, a packaging method according to claim 1 is provided. According to the invention, in a second embodiment a packaging method according to claim 2 is provided.

In a third embodiment, the method further comprises providing a second vacuum chamber and, optionally, operating the second vacuum chamber substantially in parallel with the vacuum chamber.

The advantages of the packaging method and of the packaging apparatus include that the packaging process can be carried out using a single vacuum chamber. This can also lead to a decrease in processing times and / or processing costs.

The advantages of the packaging method and of the packaging apparatus include that the evacuation station allows scaling the evacuation procedure to optimize the duration of the evacuation with respect to the operation and / or production rate of the remaining stations or operating stages included. in the packaging apparatus or procedure.

The advantages of the packaging method and the packaging apparatus also include that larger products can be packaged efficiently, regardless of the size of the vacuum chamber.

The advantages of the packaging method and of the packaging apparatus further include that the risk of deterioration of the products (eg, mold caused by residual oxygen) can be reduced by providing the packing with a shielding gas before gas extraction. or air.

The packaging procedure can also facilitate the integration and complete automation with a horizontal filling and sealing device (HFFs).

Brief description of the drawings.

FIGS. 1 and 2 represent a first embodiment of a packaging apparatus for implementing a method according to the present invention;

FIG. 3 shows a cross-sectional view of a part of a gas extraction station for implementing a method according to the present invention;

FIG. 4 shows a cross-sectional view of a part of a gas extraction station, for implementing a method according to the present invention, which illustrates a particular profile of the parts terminals of first and second members of the vacuum chamber, as well as a schematic drawing of the gas flow;

FIG. 5 shows an isometric view of a part of a gas extraction station for implementing a method according to the present invention;

FIGS. 6 and 7 represent a second embodiment of a packaging apparatus for implementing an additional method according to the present invention;

FIG. 8 shows a cross-sectional view of a part of a gas extraction station for implementing a method according to the present invention;

FIGS. 9 and 10 show a cross-sectional view of a gas extraction station for implementing a method according to the present invention;

FIGS. 11A to 11I show a cross-sectional view of a gas extraction station, and the corresponding displacement means, for implementing a method according to the present invention, representing different stages of the gas extraction process;

FIG. 12 shows an isometric view of a third embodiment of a packaging apparatus, according to the present invention, employing a gas extraction station having two vacuum chambers arranged in parallel; Y

FIGS. 12A and 12B show detailed views of the gas extraction station of FIG. 12

Detailed description

FIGS. 1 and 2 represent a first embodiment of a packaging apparatus for a method according to the present invention. The packaging apparatus 1 comprises a sealing station 3, a gas extraction station 35 and a displacement means 30. The packaging apparatus 1 further comprises a charging station (not shown). The displacement means 30 is configured to move a product 20, placed inside a film 21, from the loading station to and through the sealing station 3 and to and through the gas extraction station 35.

Normally, the products 20 are loaded onto a continuously supplied film, for example, from a roll of film (not shown), the film being subsequently sealed longitudinally in order to create a sequence of products 20 placed on the tubular film 21. Optionally, a discharge device 34 can be provided to discharge a gas or a mixture of protective gases into the interior of the tubular film 21. The gas or gases may comprise or consist substantially of CO ² .

The products to be packaged adopt different packing states (eg, 20a, 20b, 20c, 20d). The states 20a, 20b, 20c and 20d indicate that a product 20 is in different packaging stages. For example, the state 20a means that the product 20 is placed inside the tubular film 21, the state 20b means that the product 20 is contained in a semi-sealed package (i.e., a package having a sealed end and an end). open), and states 20c and 20d mean that the product 20 is contained in a sealed package (ie, a package having two sealed ends, in which the gas has or has not been removed from the package).

In state 20a, the film 21 is placed around the product 20 or the product 20 is placed in a tubular film 21. Alternatively, in the state 20a the product 20 is placed in the film 21, which is subsequently folded and sealed by its longitudinal edges to form a tubular film 21. This step can be carried out at the loading station and / or at a longitudinal (separate) sealing station.

The sealing station 3 comprises a sealing and cutting upper member 31 and a lower sealing and cutting member 32 configured to seal and cut the film 21. The sealing and cutting members 31 and 32 are configured to create a first seal on the seal. film 21, thereby creating a semi-sealed package 23 containing the product 20 in the state 20b and separating the semi-sealed package 23 from the continuously supplied film 21 which is sealed at the downstream end of the film. The product 20 in the state 20b is located within the film 21 and the semi-sealed package 23 comprises a sealed end and an open opposite end.

The gas extraction station 35 is configured to create in the film 21 a second seal at the second open end of the semi-sealed package, thereby creating a sealed package 24. In the state 20d, the product 20 is located inside the film 21 and the sealed package 24 comprises a sealed first end and a sealed sealed second end. The sealed first and second ends may also be located not directly opposite each other, for example, in cases where one of the seals has been created at an angle with respect to the longitudinal extent of the package and / or the lateral extension of the other seal. . In another embodiment, the gas extraction station 35 assumes the function of the sealing station 3, since while the gas is withdrawn from a semi-sealed package, the gas extraction station 35 performs the sealing and cutting as shown in FIG. described above with respect to sealing station 3. The concept can be visualized based on the embodiment shown in FIG. 2. Instead of operating only at one end of the packages 24 in the 20d state (see the left side of the gas extraction station 35), it can be imagined that the package 23 immediately to the right of the extraction station 35 of gas (see the packaging / product directly below the arrow 30a) is sealed by the downstream end of the package at the same time that the members 351 and 352 are in contact with each other to extract the gas from the preceding package and seal the package afterwards. of extraction. The sealing by both ends, upstream and downstream, of the gas extraction station 35 could be effected substantially at the same time.

The gas extraction station 35 comprises a first member 351 (or upper) and a second member 352 (or lower), which can be carried from a first configuration, in which the members 351 and 352 are separated from each other (see FIG. 1), to a second configuration in which the members 351 and 352 are substantially in contact with each other (see FIG 2). In some embodiments, the members 351 and 352 are, in the second configuration, in contact with each other along the perimeter of the members 351 and 352, except for at least one opening that is formed between the members 351 and 352. cross section taken along a horizontal plane (i.e., a plane parallel to a horizontal work surface of the packaging apparatus 1, eg, the upper surface of the conveyor belt 30), the members 351 and 352 may have a substantially rectangular shape. Members 351 and 352 are configured to define, in the second configuration, a vacuum chamber 353. FIGS. 1 and 2 show the members 351 and 352, as well as the vacuum chamber 353, in vertical cross section (see above with respect to the horizontal cross section). Therefore, the front and rear side walls (i.e., the walls parallel to the view plane) are not shown in order to visualize the interior of the vacuum chamber 353.

With respect to FIGS. 1 and 2, the packaging apparatus 1 further comprises a control unit 50. The control unit is connected (the individual connections for clarity are not shown) to one or more components of the packaging apparatus 1, including the charging station, the sealing station 3, the sealing and cutting members 31 and 32, travel means 30, members 351 and 352, and discharge device 34. The discharge device 34 can be provided to discharge a gas or a mixture of protective gases into the packaging film 21. The control unit 50 is further connected to the gas extraction station 35, in which the gas is extracted from the semi-packaged products in the state 20b and in which they are sealed (and, therefore, are brought to the 20d state).

The control unit 50 can also be connected to additional components, such as a hot air or retraction tunnel 33, in which the film material surrounding the products 20 packed in the state 20d can be further retracted after being sealed. It is noted that the gas extraction station 35 may comprise any means for gas extraction known in the art. FIGS. 1 and 2 do not show, for greater clarity, the individual connection lines between the control unit 50 and other components. It is understood that the packaging apparatus 1 may comprise common connection means for connecting the control unit 50 to other components, for example, electrical, optical or other connections and / or conductors.

The control unit 50 can be configured to control the transport of the products 20 along a predefined path, for example, by controlling a motor, comprised in the displacement means 30, according to a step-by-step movement or according to a continuous movement. The control unit may also control the actuators of different components as described below, for example, to create transverse seals in the tubular film or to activate members 31, 32, 351 and / or 352.

The control unit 50 may comprise a digital processor (CPU) with memory (or memories), an analog type circuit or a combination of one or more digital processing units with one or more analog processing circuits. In the present description and in the claims it is indicated that the control unit is "configured" or "programmed" to execute certain stages. This can be achieved in practice by any means that allows to configure or program the control unit. For example, in the case of a control unit comprising one or more CPUs, one or more programs are stored in an appropriate memory. The program or programs contain instructions that, when executed by the control unit, cause the control unit to execute the steps described and / or claimed in relation to the control unit. Alternatively, if the control unit is of the analog type, then the circuitry of the control unit is designed to include circuitry configured so that, in use, it processes electrical signals to execute the stages of the control unit disclosed in this document. .

The control unit 50 is connected to evacuation means (not shown) and is configured to send and / or receive control signals to / from the evacuation means. The control unit 50 can be further configured to control the evacuation means in order to provide an internal vacuum pressure to the vacuum chamber 353. For this purpose, the control unit 50 can be configured to control a vacuum pump connected to the vacuum chamber 353.

The control unit 50 can be configured to control the movement means 30. For example, the control unit 50 can be configured to increase or decrease the operation speed of the movement means 30. The control unit 50 can be configured to control the speed of operation of the displacement means 30 depending on the position of the products 20 with respect to different components of the packaging apparatus 1 (for example, with respect to the sealing station 3). or the gas extraction station 35).

The control unit 50 may be additionally or alternatively configured to control the sealing and cutting members 31 and 32. The control unit 50 can also be configured to control the sealing members 31 and 32 and cutting depending on the position of the products 20 with respect to the evacuation means and / or the sealing and cutting members 31 and 32. For example, the control unit 50 can be configured to activate the sealing and cutting members 31 and 32 depending on the position of the products 20 and / or the tubular film 21 with respect to the outlet and / or the members 31 and 32 of sealing and cutting.

In particular, the control unit 50 can be configured to control one or more components depending on the signals sent to other components and / or received from them. For example, the control unit 50 can be configured to control the activation of one or more components depending on the position of the products 20 and / or the tubular film 21 with respect to other components of the packaging apparatus 1. In this way, the control unit 50 can activate, for example, the sealing and cutting members 31 and 32 when two subsequent products 20 are in the state 20a, whereby the first seal between the two is created in the film 21. 20 products and the film is cut accordingly.

After the creation of the first seal and the cutting of the film 21 the semi-sealed packages 23 are moved, along the direction of travel 30a through the packaging machine, to the gas extraction station 35 and through Of the same. In FIG. 1, the members 351 and 352 are in their first configuration, in which a semi-sealed package 23 can be moved through the open vacuum chamber 353. Before the semi-sealed package 23 leaves the gas extraction station 35, the semi-sealed package 23 is positioned in such a way that the second open end thereof is, at least partially, inside the vacuum chamber 353 open In detail, it is ensured that the respective product 20 contained in the semi-sealed package 23, as well as a non-terminal part of the film 21 at the second open end of the semi-sealed package 23 is outside the open vacuum chamber 353, while a terminal part of the film 21 at the second open end is still inside the open vacuum chamber 353. Accordingly, an intermediate part of the film 21 at the second open end of the semi-sealed package, and extending between the non-terminal and terminal parts, is located between at least a section of the members 351 and 352.

The members 351 and 352 are now brought into their second configuration, in which the members 351 and 352 are substantially in sealed contact with each other, thus defining the closed vacuum chamber 353. The contact between the members 351 and 352 is substantially sealed (eg, air tight), except for an elongated opening in which the members 351 and 352 are coupled to the intermediate part of the second open end of the semi-sealed package 23. without creating a watertight seal along the opening.

This configuration facilitates at least the following effects on the extraction of gas from the vacuum chamber 353. On the one hand, a gas flow is created through the opening into the interior of the vacuum chamber 353, between the opposing surfaces of the members 351 and 352 and the corresponding surfaces of the intermediate part of the second open end, interposed between the members 351 and 352. This gas flow causes the adjacent layers of film at the second end of the semi-sealed package 23 to adopt and / or maintain a substantially separate configuration (i.e., the opposite layers of film are separated from each other). the other). On the other hand, the gas is not only sucked from the outside of the vacuum chamber 353 and the semi-sealed package 23, but also from the inside of the semi-sealed package 23, thus extracting the air from the semi-sealed package 23. Normally, the gas sucked from the outside is air and the gas sucked from the inside of the semi-sealed packaging is a gas or a mixture of protective gases, such as CO ² . This procedure is described in more detail below.

When the gas has been removed from the semi-sealed package 23, a sealing assembly, normally integrated in the gas extraction station 35, creates a second seal at the second open end, thus sealing the package and transforming the semi-package. sealed 23 in a sealed package 24, which contains the product 20 in the state 20d (see left of FIG 2), and from which substantially all of the inner gas has been extracted. Optionally, a surplus outer part of the film material of the second end (which is now sealed) is cut from the sealed package 24.

With respect to FIGS. 1 and 2, the displacement means 30 may comprise one or more conveyor belts 30. The one or more conveyor belts are configured to transport the products 20 in the states 20a, 20b and 20d, for example as packagings 22, 23 and 24, along a predefined path through the packaging apparatus 1. For example, the packaging apparatus may comprise several conveyor belts 30 (e.g., three, as shown in FIGS 1 and 2). A first conveyor belt 30 is configured to transport the products 20 and / or the film 21 upstream of the sealing and cutting members 31 and 32. A second conveyor belt 30 is configured to transport the products 20 and / or the packagings 22 and 23 downstream of the sealing and cutting members 31 and 32. And a third conveyor belt is configured to transport the packages 24 downstream of the gas extraction station 35.

FIG. 3 shows a cross-sectional view of a part of the gas extraction station 35 for implementing a method according to the present invention. In general, the interior of the vacuum chamber 353 and the ambient atmosphere (eg, around the chamber and / or the semi-sealed package 23) are connected through one or more channels extending along or near of opening 354 and through it. In this case, the different parts of the second open end of the semi-sealed package 23 appear as terminal part 236, intermediate part 234 and non-terminal part 232. It is noted that "terminal" refers to the outermost part of the film 21 in the second open end of the semi-sealed package 23, which has been cut from the continuous film 21 and that has not been sealed (see the previous description of FIGS 1 and 2). FIGS. 3, 4 and 5 are not to scale for reasons of clarity. In general, the height of the opening 354 is typically from 0.3 mm to 1 mm or approximately 8 to 20 times the thickness of a single layer of film 21. In some embodiments, the height of the opening 354 is 0.8 mm , 0.5 mm or 0.4 mm. The film 21 typically has a thickness between 30 pm and 60 pm, preferably between 40 pm and 55 pm, more preferably between 45 pm and 52 pm.

As shown in FIG. 3, the members 351 and 352 make contact with the intermediate part 234 of the second open end without creating a hermetic seal between the interior of the vacuum chamber 353 and the ambient atmosphere. The channels between the two volumes (i.e., the volume within the vacuum chamber 353 and the volume outside it) can be created mechanically between the members 351 and 352 and the non-terminal part 232, the intermediate part 234 and / or the terminal part 236 to guarantee a possible air flow due to the pressure differential created by means of gas extraction from the vacuum chamber 353. In other words, the gas or air from the outside of the semi-sealed package can pass between the members 351 and 352 and the terminal part 232 (channels C1), between the members 351 and 352 and the intermediate part 234 (channels C2), and / or between the members 351 and 352 and the terminal part 236 (channels C3). It is noted that the individual separation of the channels does not have to be identical on both sides (eg, upper and lower) of the film material of the second open end. For example, the size (e.g., height) of a C2 channel between member 351 and intermediate portion 234 (ie, channel C2 on the upper side of intermediate part 234) need not be identical to the size of a channel C2 between member 352 and intermediate part 234 (i.e., channel C2 on the underside of intermediate part 234). Due to various effects (eg, gravity, turbulence, pressure and / or non-identical pressure variations) acting on the flexible film material, the dimensions of the channels can vary before, during and after the extraction of gas. The same applies to channels C1 and C3. Additionally, the separation between the film material may vary along the opening 354, for example, due to a corrugated shape of the film material at the second open end of the semi-sealed package.

The width of the opening 354 may vary according to the application and, preferably, is designed to coincide with the size of the product with respect to the width of the product or a multiple thereof, in addition to a certain margin. This means that the vacuum chamber 353 can be sized to meet the width of the product in the sense that the opening 354 largely corresponds to the width of the film 21 at the second open end (when it has been brought to a flattened configuration, as shown in FIGS 3 and 4), while the width of the opening must be slightly larger than the film to take into account the tolerances of position or manufacture during packaging. In addition, large portions of the opening 354 unoccupied by the film material should be avoided due to the resulting loss of resistance to gas flow in the areas adjacent to the film material and the subsequent loss of gas flow through the film. opening in the areas occupied by the film material. That said, it is possible to extract gas from two or more semi-sealed packages 23, located side by side, providing a vacuum chamber 353 (and, therefore, an opening 354) having a width that is multiple of the width of the package , or larger, (for example, up to 33% wider, in some embodiments, 25% wider). In some examples, the gas can be extracted from three or more semi-sealed packages 23, in parallel, in a gas extraction station having an operating width of up to 1000 mm (i.e. having an opening of 1000 mm. width). In some embodiments, the gas extraction station has an operating width (ie, the opening has a width) of 900 mm. In other embodiments it has a width of 450 mm. In reference to a part of the opening occupied by the material of the film, the second ends of several semi-sealed packages may occupy 70-90% of the opening, preferably 75-80% of the opening.

The different effects that facilitate the gas extraction of the packages are explained in more detail with respect to FIGS. 4 and 5. FIG. 4 shows a cross-sectional view of a part of the gas extraction station 35, for implementing a method according to the present invention, which illustrates a particular profile of the terminal parts of the members 351 and 352, as well as a drawing schematic of the gas flow. A key problem in extracting gas from semi-sealed packages is to ensure that the open end of the package is sufficiently open to facilitate aspiration of gas from the interior of the package. In some cases, the film material tends to adhere to the adjacent film material, thereby substantially and temporarily closing the open end of the semi-sealed package and preventing gas removal from the package. In other cases, the film material partially adheres to the adjacent film material,

One way to separate opposing film layers or to prevent the opposing layers from adhering to each other is to create a transition from a relatively high pressure area and low speed (shown as HP / LV in the upper left part of FIG. to a relatively low pressure and high velocity area (shown as LP / HV) or vice versa and, optionally, back to back (shown as HP / LV to the right). In this case, the transition from high to low pressure (or vice versa), as well as the transition from low speed to high speed (or vice versa) in combination with the excitation of the material of the film (for example, due to turbulence and / or the gas flow) can cause the layers of the contact film material to stop adhering and to separate from each other by the gas flow pressure differential, the speed differential and / or the friction effects. Furthermore, the position of the film layers in the opening can influence the properties of the gas flow in a self-regulating manner. For example, if a channel between a film layer and one of the members 351 and 352 becomes smaller (or larger), the pressure and velocity of the gas flowing through the channel varies accordingly and, therefore, can in turn influence the position of the film, thus changing the size of the channel.

The gradient of the pressure / velocity changes in the transition between the HP / LV and LP / HV areas can be modified by providing D, F, D 'and / or F' edges with corresponding profiles. The modification of the shape of the edges D, D ', F and F' affects the gas flow in the associated areas and can, for example, facilitate or prevent the delamination of the gas flow or facilitate or prevent turbulence. The individual effect may be the result of the effects of the corresponding shape on the gas flow (eg pressure, velocity, direction, etc.). The edges D and D 'indicate in the figures entry edges, while the edges F and F' indicate exit edges, with reference to the gas flow when extracting the gas from the vacuum chamber 353. As shown in FIG. 4, the edges D, F, D 'and F' may have a substantially rounded shape, for example, defined by a radius of between 1 and 5 mm, in some embodiments, preferably 2 mm or 2.5 mm. It is noted that the edges D, F, D 'and F' may have the same or different shapes, in particular, the entrance edges D and D 'may have a different shape to the exit edges F and F', but also that edges D or F of member 351 may have a different shape to edges D 'or F' of member 352.

FIG. 5 shows an isometric view of a part of a gas extraction station 35 for implementing a method according to the present invention. In this case, a particular profile of the members 351 and 352 is illustrated. The parameters characterizing the members 351 and 352, as well as the opening 354, include: depth C, height B, width A, angle G and radii D , E and F. The opening 354 has a height B of 1 mm or less, preferably between 0.4 and 0.8 mm (eg, 0.4 mm, 0.5 mm or 0.8 mm). The opening 354 further has a width of 1000 mm or less (eg, 900 mm), preferably 500 mm or less (eg, 450 mm). The opening 354 further has a depth of 50 mm or less (eg, 45 mm), preferably 20 mm or less (eg, 20 mm), and most preferably 12 mm or less (eg, 12 mm). The shape of the entrance edge D is based on a curvature defined by a radius of 5 mm or less, preferably 2.5 mm or less (for example, 2.5 mm or 2 mm). The shape of the inclination edge E is based on a curvature defined by a radius of 50 mm or less (e.g., 50 mm), preferably 30 mm or less (e.g., 30 mm). The inclination edge E may be present (ie, the corresponding radius is greater than 0) or not present (ie, the corresponding radius is equal to 0). The shape of the trailing edge F is based on a curvature defined by a radius of 10 mm or less (for example, 9 mm), preferably 5 mm or less (for example, 2 mm). Corresponding edges D ', E' and / or F '(not shown) associated with member 352 may have the same properties as those described above with respect to edges D, E and F, although individual values do not have to be identical (for example, edge D is based on a radius of 2.5 mm and edge D 'is based on a different radius). The thickness H refers to the thickness of the film material, while H denotes the thickness of two layers of film material, since an open end of a semi-sealed package, as described, comprises at least two layers of material of movie. The width of the second open end of the semi-sealed package 23 or of the package 24 can be defined by a percentage of A with reference to the width A of the opening 354. The second end of the package 23/24 can have a width of, for example , 70-90% of A, preferably 75-80% of A.

Another effect that occurs, predominantly with members 351 and 352 having profiles such as described above and with reference to FIG. 5, refers to the characteristics of the gas flow through the opening and along the profiles of the members 351 and 352. It is noted that the cross section of the opening is not constant along the depth C of the opening (see "C" in FIG.5) and, in particular, increases from the inclining edges E and E 'towards the exit edges F and F'. The gas flow along the surfaces of the members 351 and 352 tends to follow the shape of the surfaces due to the viscosity effects between the gas flow and the adjacent surfaces, as well as the Coanda effect. The same effects occur between the gas flow and the surfaces of the film material of the packaging 23. Since the gas flow between the film material and, for example, the member 351 tends to follow the surface (i.e. shape of the surface) of both the film material and the member 351, the gas flow must expand and slow down, thereby exerting a force on both surfaces directed toward the gas flow. In other words, the gas flow will push both the film and the respective member towards each other. As the members 351 and 352 remain fixed in their respective positions, essentially they are the layers of film material, in the intermediate and terminal parts of the second end, which are separated from each other. This separation action creates and / or maintains a channel extending from the inside of the package towards the second end, through which the gas can be evacuated from the inside of the package.

The individual parameters to achieve the above effects vary according to the individual application. For example, a thicker film material may require a different pressure differential gradient than the thinner film material. In addition, the values of the different pressures and gas flow rates are also decisive factors. The following table 1 of examples illustrates different combinations of parameters that have proven to be effective with respect to the first embodiment described above. In these examples, an opening of the semi-sealed processed packagings was ensured and an efficient extraction of the gas from the packagings was achieved.

Table 1

In general, the described method and apparatus can be used in combination with a large number of known film materials. In some examples, the film materials used have the properties listed in the following table 2 (LD denotes longitudinal direction, TD denotes transverse direction). It is noted that these films are merely examples that show the applicability of the described method and apparatus.

Table 2

FIGS. 6 to 8 represent a second embodiment of a packaging apparatus for implementing an additional method according to the present invention. In general, the components work in the same manner as described above with respect to the first embodiment and as shown in FIGS. 1 and 2, unless specifically described otherwise below. The same reference numbers in FIGS. 6 and 7 denote components corresponding to those of FIGS. 1 and 2. Unless otherwise indicated, said components have a function and properties equal to those described above.

The sealing and cutting members 31 and 32 are, in the second embodiment, configured to create not only a first seal in the tubular film 21 but also a second seal. In this way, the products 20 placed inside the tubular film 21 leave the sealing station 3 in the state 20c, namely in a sealed packaging 24 '(instead of the state 20b and in a semi-sealed package 23). A sealed packaging 24 'differs from a sealed packaging 24 in that the gas present in the packaging 24' has not yet been removed. As shown, the displacement means 30 move the packages 24 'to the gas extraction station 35 and through it. The gas extraction station 35 functions essentially the same as that described above, although it is adapted to handle sealed packages in the manner described below. After removing the gas from the packaging 24 ', thereby transforming the packaging 24' into the sealed packaging 24 (and with the extracted gas), the displacement means 30 move the packages 24 away from the gas extraction station 35.

As can be seen in FIG. 7, the sealed packages 24 are placed with respect to the vacuum chamber 353 so that, by bringing the members 351 and 352 to their second configuration, the second end (in this case sealed) of the package 24 'is hooked by the members 351 and 352 so that a non-terminal part of the second position is located outside the vacuum chamber 353, an intermediate part of the second end is engaged by the members 351 and 352, and a terminal part of the second end is located within the the vacuum chamber 353. The configuration is largely identical to that described above with respect to the first embodiment and the semi-sealed package, with the exception that the second embodiment is configured to process sealed packages. The details of the extraction process gas described in more detail with respect to FIGS 8-10 ^s.

FIG. 8 shows a cross-sectional view of a part of a gas extraction station for implementing a method according to the present invention. The members 351 and 352 come into contact with the sealed end of a sealed packaging 24 'in an intermediate part of the second end. It is noted that the non-terminal portion (232), intermediate portion (234) and terminal portion (236) of a second end of a sealed package correspond to what is shown with respect to a semi-sealed package 23 in FIG. 3. For clarity, these portions are not shown in FIG. 8. When the members 351 and 352 are brought to their second configuration, the terminal part of the second end, as well as the rest of the package 24 '(outside the vacuum chamber 353) expand slightly due to the gas present in the The middle part of the second end is pushed outward both in the direction of the terminal part and the non-terminal part of the second end. In addition to the components described above, the vacuum chamber 353 may further comprise the first fastening members 355 and second 356 that contact the outermost portion of the terminal portion of the second end. This can be done to keep the terminal part fixed at a particular position within the vacuum chamber 353.

A puncture means 359 serves to provide an opening 241 to the end portion, thereby providing a possible passage of gas from inside the package 24 'to the vacuum chamber 353. In general, in this case any suitable puncture means may be employed to puncture the end portion of the second end, for example, a punch (e.g., creating a substantially round hole by punching or stamping) or a hot wire suitably (for example). example, a hot wire in the shape of a horseshoe that creates a corresponding hole, substantially round, when thermally cutting the film). The lancing means is preferably configured to provide the end portion of the second end with a hole that prevents (additionally) the breakage of the film material, which may occur, for example, by creating a simple (linear) cut or an opening that have sharp corners. After extraction of the gas from the vacuum chamber 353, the terminal part expands (see the double arrow pointing outwards in FIG 8) due to the differential pressure between the interior of the package 24 'and the interior of the chamber 353 of emptiness. The expansion of the terminal part causes the film material of the second end to maintain a separate configuration, thus ensuring that the gas inside the package 24 'can flow towards the non-terminal part, the intermediate part and the terminal part of the second end, and through them, before passing through the opening 241 and entering the vacuum chamber 353 as indicated by the dashed arrows. In this way the gas is removed from the packaging 24 'which is subsequently sealed with the corresponding sealing means (not shown in FIG. 8). The sealing means may comprise sealing rods as is known in the art (for example, similar to sealing and cutting members 31 and 32) and may, for example, be integrated into members 351 and 352 or provided as separate units. , outside the vacuum chamber 353, and configured to seal the package 24 'and cut an outer portion of the second end of the package 24', thus providing a sealed package 24 from which the gas has been extracted (see FIG. . It is noted that the puncture of the terminal part can be effected, alternatively, once gas extraction has begun and while it is in progress. In this case, the expansion of the terminal part, caused by the pressure differential and regardless of whether the opening 241 is present or not, can serve to counteract the action of a punch or other puncture means, thus facilitating accurate positioning and reliable puncture means and creation of the opening 241.

FIGS. 9 and 10 show a cross-sectional view of a third embodiment of a gas extraction station for implementing a method according to the present invention. FIGS. 9 and 10 illustrate one of the advantages of the present invention, as well as the additional components associated with the vacuum chamber 353. The product 20, as shown in FIGS. 9 and 10, is illustrated as a much larger object than in the remaining figures. It is noted that the size of the vacuum chamber and, therefore, of the opening 354, simply limits a dimension of the potential size of the products to be processed, i.e., the width of the package. As shown in FIGS. 9 and 10, the size (for example, the length) of a product 20 does not affect the gas extraction process because only a part of the sealed (or unsealed) end of the package must fit into the vacuum chamber 353, instead of the entire product. In addition, the height of the product 20 only has a negligible impact on the gas extraction process, in the sense that the operative height of the members 351 and 352, as well as the clearance between the two members 351 and 352, when found in the first configuration, can be adjusted accordingly.

FIG. 9 shows the members 351 and 352 in their first configuration, allowing to place a package 24 'in such a way that the non-terminal, intermediate and terminal parts of the sealed end of the package 24' can be positioned as described above. In addition, the members 351 and 352 are respectively associated with the cutting means 357 and 357 ', as well as with the sealing means 358 and 358'. Adjacent the cutting means 357 and 357 ', the members 351 and 352 have a curved shape for contacting the intermediate part of the second end of the package 24'. The sealing means 358 and 358 'are disposed adjacent to those.

FIGS. 11A to 11I show a cross-sectional view of the third embodiment of a gas extraction station and of the corresponding displacement means for implementing a method according to the present invention, representing the different stages of the gas extraction process in accordance with the third embodiment. The direction of movement of the packages through the packaging apparatus is from right to left, corresponding to FIGS. 1, 2, 6 and 7. In Fig. 11A, the members 351 and 352 are in the first configuration, so that a sealed package 24 'can be moved along the members 351 and 352 to a position in which a terminal part of the packaging 24 'is located between the members 351 and 352 but in which the product is located outside the area affected by members 351 and 352. In FIG. 11B an optional step for adjusting the displacement means 30 is illustrated. In some embodiments, the displacement means 30 are adjustable in order to facilitate efficient movement of the packages through the packaging apparatus, while assisting the positioning of the packages with respect to the members 351 and 352. As illustrated , a section of the movement means can adopt a transport configuration in which the packages can be moved through the station 35 and a gas extraction configuration, in which a package is located with respect to the members 351 and 352 in order to facilitate the extraction of gas from the packaging. In FIG. 11C, the members 351 and 352 are brought to the second configuration and, as shown in FIG. 11D, the cutting means 357 is activated to cut off excess film material from the terminal part of the package, thereby opening the package again. Substantially at the same time as the package is opened (ie shortly before or after) the chamber 353 is evacuated, such that a pressure differential is created between the interior of the chamber 353 and the outside atmosphere. In FIG. 11E it can be seen that the excess film material has fallen into a receptacle (or has been otherwise eliminated) and that the gas is removed from the interior of the 24 'package (showing that the residual gas between the film and the film has been reduced). the product 20). Accordingly, the packaging film 24 'approaches the product 20 as the gas is extracted. FIG. 11F shows the final stages of gas extraction, in which the film is tightly attached to the product 20 and the gas has been substantially extracted from the packaging 24 '. The evacuation of the chamber 353 is then stopped and the package 24 'is resealed with the sealing means 358 and 358'. In FIG. 11G the sealing means 358 and 358 'are removed and in FIG. 11H members 351 and 352 adopt the first configuration (ie, camera 353 is open), thereby releasing packaging 24 '. Optionally, a section of the displacement means 30 is adjusted to move the package 24 'forward and / or to receive a subsequent package. FIG. 11I shows how the subsequent packing moves between the members 351 and 352 in their first configuration and, therefore, through the open chamber 353, to be positioned as described above. The procedure starts again with the subsequent packing 24 ', as described above.

FIG. 12 shows an isometric view of a third embodiment of a packaging apparatus for implementing another method, according to the present invention, which employs a gas extraction station 35 'having two vacuum chambers 353' arranged in parallel. The gas extraction station 35 'of the packaging apparatus 1' includes two vacuum chambers 353 'arranged on each side of a feed belt 30i. As shown in FIG. 12, the products 20 can enter the gas extraction station 35 'along the direction 30a of movement, by means of a feeding belt, for example in the form of pillow-like boxes (ie, packages 24', preferably washed with an inert gas and sealed at both ends, which have not yet been subjected to gas extraction, see also the above description of FIGS 6 and 7). The control unit 50 is configured to control a half transverse conveyor 30m to receive the packages 24 'through the feed belt 30i along the direction 30a of movement and to selectively move the packages 24' to the left as far as possible. along the path 30a-I or to the right along the path 30a-r, respectively, on additional transverse conveyors 301 or 30r. A respective vacuum chamber 353 'is located on each side of the average transverse conveyor 30m.

The vacuum chamber 353 'corresponds structurally and functionally to the vacuum chambers 353 described above. Therefore, vacuum chambers 353 'can include members 351' and 352 'and can be configured to open and close (not shown in FIG. 12 for clarity) as described in detail above. Additional components, for example, actuators configured to move members 351 'and / or 352', are not shown in FIG. 12 for clarity. The packages 24 'traveling along the paths 30a-I and 30a-r can be moved to laterally introduce the upstream end of the package into the open vacuum chambers 353'. The vacuum chambers can then be closed and the evacuation performed as described above. In this way, the two vacuum chambers can operate alternately (substantially parallel and / or independent of each other) and, during each cycle of operation of a respective vacuum chamber 353 '(eg, opening, insertion of the upstream end). of one or more packages, closure, evacuation, reopening), one or more packages 24 'can be evacuated using the respective vacuum chamber 353' (for example, left or right). It is understood that the vacuum chambers 353 'can be operated substantially independent of each other, for example in order to take into account different evacuation times, packages 24' of different sizes, etc.

Substantially upon introduction (eg, at the same time or shortly before or after) of the upstream end of the package 24 'into the opening (see state 20c in FIG. 12), the film material at the current end above it can be perforated or pinched to facilitate the subsequent gas extraction. The piercing can be performed using drill rolls 360 (see FIGS 12A and 12B). As the upstream ends of the packages are introduced into the vacuum chamber 353 ', the gas or air can be evacuated from the interior of the package by closing the vacuum chamber 353' as described above. When the gas extraction is complete, the sealing and cutting is performed as described above to free the vacuum chamber 353 'from the packages 24', now evacuated (see state 20d in FIG. 12).

FIGS. 12A and 12B show detailed views of the gas extraction station of FIG. 12. The control unit 50 is operatively connected to the middle transverse conveyor 30m, to the left transverse conveyor 301 and to the right transverse conveyor 30r. The average transverse conveyor is controlled to receive the packages and to move them laterally in any direction towards and on the respective transverse conveyor (for example, 301 or 30r). The lateral transverse conveyors are controlled to receive a corresponding package and to move its upstream end to and through the respective clamping station 360 and, further, to the respective open vacuum chamber 353 'as described above. The pinching station 360 pierces the respective package and the package is evacuated while the perforated upstream end of the package is placed inside the vacuum chamber 353 ', the film extends into the vacuum chamber 353 through the opening . After gas extraction, the respective vacuum chamber 353 'opens and the packages 24' move further along the paths 30a-l and 30a-r, respectively, and return to the average transverse conveyor 30m and the belt 30o output in order to be placed in an outlet part of the packaging apparatus 1 '.

The pinching station 360 may include pinching rollers with protrusions 360 ', on the peripheral surface of the roller, configured to, in combination with recesses 360 "present on an opposite surface, perforate a film 21 supplied to the station 360 of As shown, the pinching station 360 can be implemented as a set of opposing rollers carrying, for example, protuberances 360 'and recesses 360 "(alternatively also any combination of protuberances and / or recesses configured to create one or more openings, see also above). It is noted that other means can be used to perforate the film 21 (eg, hot wires as mentioned above or knife rolls configured to cut along an upstream edge of the package) provided that it is ensured that the The seal established by the film 21 at the front end of the package 24 'is capable of facilitating gas extraction as described above in detail.

In some embodiments, several subsequently processed packages are directed to the vacuum chambers 353 'in an alternative manner, so that each vacuum chamber 353' receives, for example, each second package of a series of packages (alternatively, any number of packages). 24 'subsequent packagings - for example, 3 - can be directed to one of the vacuum chambers 353' for evacuation). Each vacuum chamber 353 'can be sized and configured to be able to process several packages simultaneously, for example, between 2 and 5 packages, preferably at least 3 packages as shown in FIG. 12. The evacuation station of the packaging apparatus 1 'has a modular structure, which allows the simultaneous use of two or more vacuum chambers 353'. This modular design can prevent or alleviate a bottleneck situation, in which the packaging apparatus 1 'can operate only at the speed of the slowest station of the same.

The packaging apparatus 1 may comprise an HFFS machine. The HFFS machine may comprise a conveyor belt 30 for supporting and transporting the packages 22 in a horizontal direction. The product 20 can be arranged on a surface. The surface can extend substantially in the horizontal direction. The surface may comprise the upper surface of a conveyor belt 30. The conveyor belt 30 may be a continuous conveyor belt 30. For example, the conveyor belt 30 can be suspended between at least two rollers. The conveyor belt 30 can transport the product 20 in a horizontal direction.

The product 20 can be arranged in a tray. The tray supports the product 20. The tray may comprise walls that extend substantially vertically from the base of the tray to a height greater than the vertical dimension of the product 20. Alternatively, the height of the tray may be equal to or less than the height of the product 20. The packaging extends around the tray. The tray may comprise a material selected from a list consisting of polystyrene, aluminum or other thermoplastic material such as PET or cardboard. The tray can be rigid, solid or foamed, and have any color and shape.

The package may comprise a multilayer film 21. The film 21 may comprise a polyolefin. The film 21 can be a fully coextruded retractable film 21. The packaging provides a barrier for the gas to pass from the inside of the package to the outside of the package. Consequently, the environment inside the packaging is isolated from the environment outside the packaging. This helps to preserve food products 20 and avoid contamination. This can be advantageous with respect to food hygiene. The packaging can provide a barrier to odors or gases. This can be particularly useful when the product 20 is a food product. The packaging can be resistant to abuse.

The packaging can be transparent or translucent. This allows the customer to see the product 20 through the packaging. For example, the package may comprise a transparent film 21. The packaging film can have anti-fog properties. This ensures a high attractiveness for the consumer. The packaging film can be printable. This allows labels to be printed directly on the packaging.

The package can be formed from a roll of film 21. The tubular film 21 can be formed by forming a tube from the film roll 21. The packaging apparatus 1 can comprise a former configured to form the film roll 21 a tube mode. The former can form the tube by forming a longitudinal seal along the longitudinal edges of the film roll 21. The tube can be formed from two strips of film 21. In this case, the former forms two longitudinal seals as along the opposite edges of the two rolls of film 21.

The packaging apparatus 1 may comprise a discharge device 34. The discharge device 34 is configured to discharge gas through the film tube 21 that forms the package. The gas discharge prevents the tube from collapsing. The gas discharge helps to maintain a distance between a product 20 of a tray and the film 21. This helps to improve the hygienic appearance of the film 21 because the film 21 does not become stained with the product 20. The discharge device 34 expels gas longitudinally through the tube. The gas used for the discharge may comprise approximately 70% oxygen and approximately 30% carbon dioxide or another suitably modified atmosphere.

In addition, the discharged gas allows the product 20 to be packed in a modified atmosphere. The gas can help to preserve the product 20, prolonging its useful life. The desired amount of gas within each sealed package depends on the type of product 20 and the necessary shelf life.

The packaging apparatus 1 may comprise a retraction machine configured to retract the film 21. The retraction machine may be a retraction tunnel based on water or air, for example a tunnel 33 of hot air. The sealed package 24 is retracted in the retraction machine. The retraction procedure may involve heating the sealed package. The package 24 can be heated to a temperature between about 130 ° C and about 150 ° C.

Before the sealed package 24 is retracted, there may be an undesirable gas trapped in the sealed package together with the product 20. Furthermore, the sealed package 24 may comprise the undesirable "dog ears", with a dog ear being a part of the dog's ear. packaging protruding from the product 20 (for example, because the product 20 is not a regular rectangular prism). After the retraction procedure, the dog ears and the gas content are reduced. This gives the sealed package 24 a more aesthetic appearance. In the case of cheese, the cheese can consume any residual gas remaining in the sealed package 24 after the retraction step.

The product 20 can be a food product. For example, the product 20 may comprise meat, cheese, pizza, prepared dishes, chicken and fish. The product 20 may be substantially dry, as in the case of cheese. For some products, such as cheese, there is no need for a tray to support the cheese. Alternatively, the product 20 may be wet. In this case, it is particularly desirable to arrange the product 20 in a tray.

The packaging method of the invention can be used to pack food products 20 which should have a shelf life of between about six days and about 14 days, for example.

It is desirable that the packaging apparatus 1 comprises a horizontal form, fill and seal machine. However, the packaging apparatus 1 may comprise other types of forming, filling and sealing machines, such as a vertical forming, filling and sealing machine (VFFS). In a vertical form, fill and seal machine, the packages 22 are moved through the packaging apparatus 1 in a vertical direction during the packaging process.

In a VFFS machine, the package can be sealed once to form the lower end of a sealed package. Then the product 20 is introduced into the open package. The upper end of the package 22 is then sealed to form a sealed package 24 '.

Claims (11)

1. A packaging procedure comprising: providing a semi-sealed package (23) containing a product (20) to be packaged, the semi-sealed package (23) being made from a film (21) and having a first end sealed and a second end open, providing a vacuum chamber (353) including a first member (351) and a second member (352) disposed opposite the first member (351), the first member (351) and the second member (352) being relatively mobile between a first configuration, in which the first and second members (351, 352) are separated from each other, and a second configuration in which the first and second members (351, 352) are in contact with each other along a perimeter thereof, except for at least one opening (354) which is formed between the first and second members (351, 352), adjusting a spacing between the first and second members (351, 352) to bring the first and second members (351, 352) to the first configuration, thus opening the vacuum chamber (353), placing the semi-sealed package (23) and the vacuum chamber (353) relatively in such a manner that a terminal part (236) of the second end is located inside the vacuum chamber (353) and a non-terminal part (232) of the second end is located outside the vacuum chamber (353), an intermediate portion (234) of the second end passing through the opening (354), the intermediate portion (234) extending between the terminal and non-terminal portions (236). , 232) of the second end, adjusting the spacing between the first and second members (351, 352) to bring the first and second members (351, 352) to the second configuration, in which second configuration the first and second members (351, 352) are, except for the opening (354), in substantially sealed contact with each other, and the intermediate part (234) of the second end is received in the opening (354), with the first and second members (351, 352), in the second configuration creating, inside the vacuum chamber (353), an internal vacuum pressure that is lower than an ambient pressure present in the ambient atmosphere outside of the the vacuum chamber (353), selecting the internal vacuum pressure so that: - a gas flow through the opening (354) is determined which causes the opposite layers of the film (21) at the second end to maintain a substantially separate configuration, and - both the gas inside the semi-sealed package (23) and the gas in the ambient atmosphere are sucked through the opening (354), and creating a second seal in the semi-sealed package (23) at the second end, thereby forming a sealed package (24) containing the product (20) and having the first and second ends sealed. 2. A packaging procedure comprising: providing a sealed package (24 ') containing a product (20) to be packaged, the sealed package (24') being made from a film (21) and having a sealed first end and a sealed second end, providing a vacuum chamber (353) including a first member (351) and a second member (352) disposed opposite the first member (351), the first member (351) and the second member (352) being relatively mobile between a first configuration, in which the first and second members (351, 352) are separated from each other, and a second configuration, in which the first and second members (351, 352) are in contact with each other along a perimeter thereof, except for at least one opening (354) that is formed between the first and second members (351, 352), adjusting a spacing between the first and second members (351, 352) to bring the first and second members (351, 352) to the first configuration, thus opening the vacuum chamber (353), placing the sealed packaging (24 ') and the vacuum chamber (353) relatively in such a way that a terminal part (236) of the second end is located inside the vacuum chamber (353) and a non-terminal part (232) of the second end is located outside the vacuum chamber (353), an intermediate portion (234) of the second end passing through the opening (354), the intermediate portion (234) extending between the terminal and non-terminal portions (236, 232) of the second end, adjusting the spacing between the first and second members (351, 352) to bring the first and second members (351, 352) to the second configuration, in which second configuration the first and second members (351, 352) are, except for the opening (354), in substantially sealed contact with each other, and the intermediate part (234) of the second end is received in the opening (354), with the first and second members (351, 352) in the second configuration creating an opening in the film (21) in the terminal portion of the second end, and creating, inside the vacuum chamber (353), a pressure of internal vacuum that is lower than an environmental pressure present in the ambient atmosphere outside the vacuum chamber (353), selecting the internal vacuum pressure and the size of the opening so that: - an expansion of the terminal part is determined (236) which causes the opposite layers of the film (21) at the second end to maintain a substantially separate configuration, and - gas is sucked into the interior of the vacuum chamber (353) from the ambient atmosphere through the opening (354) of the interior of the package (24 ') through the opening (354) and through the opening. The method of claim 1, wherein the step of providing the semi-sealed package (23) comprises: placing a tubular film (21) around the product (20) to be packaged, and creating, in a sealing station (3), a first seal on the tubular film (21), thereby forming the semi-sealed package (23) containing the product (20) to be packaged and, optionally, creating a longitudinal seal throughout of a film (21) in order to obtain the tubular film. The method of claim 2, wherein the step of providing the sealed package (24 ') comprises: placing a tubular film (21) around the product (20) to be packaged creating, in a sealing station (3) , a first seal on the tubular film (21), thus forming a semi-sealed package (23) containing the product (20), and creating, in the sealing station (3), a second seal in the tubular film (21), thereby forming the sealed package (24 ') containing the product (20) and, optionally, creating a longitudinal seal along the a film (21) in order to obtain the tubular film. The method of one of the preceding claims, wherein relatively placing the package (23, 24 ') and the vacuum chamber (353) comprises: moving the first member (351) of the vacuum chamber (353) and / or moving the second member (352) of the vacuum chamber (353) one with respect to the other, and moving the package and / or moving the vacuum chamber (353) one with respect to the other. The method of one of the preceding claims, wherein adjusting the separation comprises: moving the first member (351) of the vacuum chamber (353) and / or moving the second member (352) of the chamber (353) of vacuum one with respect to the other. The method of one of the preceding claims, wherein adjusting the gap comprises: providing the opening (354) with a height of 8 to 20 times the thickness of the film (21), or providing the opening (354) with a height of 1.0 mm or less, preferably 0.8 mm or less, more preferably 0.5 mm or less, or providing the opening (354) with a height of between 0.3 mm and 1.0 mm, preferably between 0.3 mm and 0.8 mm, more preferably between 0.3 mm and 0.5 mm. The method of one of the preceding claims, wherein creating the internal vacuum pressure within the vacuum chamber (353) comprises creating an internal vacuum pressure of between 800 mbar and 500 mbar, preferably between 750 mbar and 525 mbar, more preferably between 700 mbar and 550 mbar. The method of one of the preceding claims, further comprising providing the interior of the film (21) and / or of the package (23, 24 ') with a protective gas, optionally the protective gas consisting substantially of CO ² . The method of one of the preceding claims, further comprising providing a second vacuum chamber and, optionally, operating the second vacuum chamber substantially in parallel with the vacuum chamber (353). The method of the preceding claim, wherein the steps of: - adjusting the spacing between the first and second members (351, 352) of the vacuum chamber (353) to bring the first and second members (351, 352) to the first configuration, thus opening the vacuum chamber (353), and - adjusting the spacing between the first and second members of the second vacuum chamber to bring the first and second members of the second vacuum chamber to a second configuration, wherein the first and second members of the second vacuum chamber are , except for an opening of the second vacuum chamber, substantially in sealed contact with each other, they are executed substantially at the same time.