EP1562827B1 - Device for packaging products under controlled atmosphere in film-sealed packages - Google Patents

Abstract

The invention concerns a filling and sealing device comprising a top part (3) in the shape of a bell and a bottom part (2) forming a dish, receiving a container (4) to be sealed by a film (11) in the chamber (25) defined by the two parts (2 and 3). The top part (3) comprises in one wall (8), on the sealing film feeding side (11), inserting and filling means (17A, 20) emerging inside the chamber (25) between the film (11) and the lower edge of the wall (8) for introducing products into the chamber (25) and filling the container (4) held therein, and above said means (17A, 20) a slot (13) for allowing through the film with sealing and locking means (14) with controlled actuation. Means (27, 28) for unwinding the film for example in the form of a push-rod are provided to introduce into the chamber (26) an extra length of sealing film (11). The invention is applicable in particular to packaging of food products under controlled or modified atmosphere, in trays or jars.

Description

The present invention relates to a filling and sealing device for a packaging machine under controlled atmosphere of products, more particularly solid food products, rigid or in pieces in containers such as trays, pots and similar packaging, sealed by a movie.

The packaging of food and other products in such sealed packages is carried out on so-called "Trays" or "Thermoformers-Trays" machines depending on whether the containers to be sealed are made beforehand on another machine, or by thermoforming for example a film of thermoplastic material on the same machine as the lidding machine. It is often necessary, especially when packaging food products, pharmaceuticals or other perishable or problematic products, for better preservation, protection and / or hygiene, to carry out sealing under vacuum or controlled atmosphere. , which implies an extraction of the air and / or an injection (or reinjection) of gas.

A known and commonly used solution is to perform the extraction of air and / or gas injection through holes made on the sides of the thermoforming film along the drive chains. This solution makes it possible to establish in the packages a well controlled atmosphere, but leads to a significant loss of thermoforming film, the latter must be much greater than the width of the containers to be sealed, but does not allow to fill products with trays in the sealing station.

Other solutions proposed up to now for this purpose (see for example US-A-4 162 599. US-A-4,624,099, US-A-5,271,207, WO 96/09210) are complicated and expensive and do not give full satisfaction. In particular, they do not allow not to achieve at sealing station a satisfactory or reliable sealing of the enclosure created around the container to be sealed, in particular at the air extraction system and / or sweep gas injection between the film of lidding and the container to seal and especially do not allow the filling of trays directly in the sealing station.

In order to overcome the drawbacks relating to faulty sealing at the sealing station, the document WO 99/17990 proposes a sealing device for a packaging machine in sealed containers, a device which, while being of particularly simple and reliable structure, , ensures a perfect seal of the enclosure in which the sealing of the lid on the container takes place, thus allowing the creation, in the sealed container, of a better controlled atmosphere than hitherto and also allowing the introduction of fluid products (for example liquid, pasty or powdered) in the receptacle inside the welding or sealing station, before complete sealing of the receptacle. This lidding device, intended for a machine for packaging products in a controlled atmosphere in containers such as trays, pots and similar containers lidded by a film, comprises an upper part forming a bell provided with a welding head, and a lower part forming tank. The lower part receives at least one container to be sealed and cooperates with the upper part so as to define, around the container to be sealed, an enclosure in which continuous lidding film previously supplied to the container is welded to the container by the head welding of the upper part. The upper part comprises, in a side wall, on the supply side of the lidding film, a passage slot for the lidding film, shut-off means and actuation-controlled locking means for closing said slot and locking the film with respect to the upper part, means for introducing and / or extracting fluid (gas, air), and possibly filling means comprising nozzles or orifices for introducing fluid products (liquid, semi-fluid); liquids, pasty or powder) opening inside the enclosure between said slot and the lower edge of said wall.

It is not intended, according to WO 99/17990, to fill the containers with non-fluid products at the sealing station.

The present invention relates to a device for packaging products in a controlled atmosphere, more particularly for filling the containers, inside the sealing station, with products even of non-fluid consistency (rigid, solid, in pieces, etc.) these products may preferably be previously placed in a modified or controlled atmosphere.

More particularly, the invention aims at a device for filling and sealing such packaging containers, having all the advantages and characteristics of the device according to WO 99/17990, thus complementary to this device, but more efficient and having a structure better adapted to an industrial process of packaging and having especially the advantage of allowing the containers to be filled directly inside the sealing station, thanks to the possibility of introduction into the chamber surrounding the container to be filled and to seal, of all types of products, of any kind, shape, appearance and consistency but more particularly of rigid products, solid or in pieces, if necessary previously put under modified or controlled atmosphere, these products may be in particular food products, such as as loins of pigs, poultry, fish such as processed or whole salmon, pâtés, vegetables, etc ...

The device according to the invention for filling and sealing packaging for a packaging machine under controlled atmosphere of products in containers such as trays, pots and similar packaging to be sealed by a film, comprises a fixed upper part forming a bell provided with a vertically movable welding head, and a vertically movable lower part forming a tank, the lower part receiving at least one container to be sealed and cooperating with the upper part so as to define, around the container to be sealed, an enclosure in which continuous sealing film previously passed through an opening in the chamber above the container disposed inside the enclosure is welded to the container by the welding head of the upper part. The device also comprises means for closing off said feed opening and blocking the lidding film in this opening and means for establishing a controlled atmosphere inside the enclosure. The device further comprises means for introduction and filling opening inside the enclosure below said sealing film for the introduction into said enclosure of the products to be packaged and for filling the container contained in said enclosure with these products, before sealing the lidding film on the container. The device further comprises lidding film scrolling means for feeding and accumulating an excess length of lidding film in the chamber, this excess length being available to allow the welding head to be lowered onto the container. to seal without tearing the lidding film.

Indeed, because of the presence of the introduction and filling means between the opening of the lidding film and the container to be sealed, this opening which can preferably be formed in the form of a slit must be provided to the way of a window in the upper part, at a distance above the container even greater than the product to be packaged is large, so that in the absence of scrolling means, the length of film that would be brought into the enclosure by the only traction exerted by the tray previously sealed, during the advancement of the latter out of the enclosure, would be insufficient to prevent tearing of the film during the descent of the welding head on the tray next.

The advantages of the device comprising these introduction and filling means completed by the film scrolling means are numerous, since this device allows, thanks to the possibility of introducing all products into containers directly into the sealing station, to improve and ensure the protection and to considerably increase the shelf life of foodstuffs and hygiene, since these products can now, for some, from the production room, to be sent, conveyed or directed directly into the sealing station of a packaging machine, or by means of dosing equipment, thereby eliminating all sources of contamination, intermediate, external and environmental, to avoid, for some fragile products such as yogurts or certain meat products, meat, fish, processed vegetables or not, etc., clean rooms, laminar flow etc ...

• les figures 1 et 2 sont des coupes schématiques d'un dispositif d'operculage selon le document WO 99/17990 ;
• les figures 3 et 4 sont des coupes schématiques de deux modes de réalisation d'un dispositif conforme à la présente invention, comportant, en plus des moyens déjà illustrés sur les figures 1 et 2, des moyens de remplissage du récipient avec des produits par exemple rigides, directement dans l'enceinte entourant le récipient au poste d'operculage ;
• les figures 5 à 10 illustrent plusieurs modes de réalisation des moyens permettant le défilement d'une longueur excédentaire de film d'operculage dans l'enceinte d'un dispositif selon la figure 3.

Referring to the accompanying diagrammatic drawings, an illustrative and non-limiting embodiment of a filling and sealing device according to the invention will be described in more detail below; on the drawings:

• Figures 1 and 2 are schematic sections of a sealing device according to WO 99/17990;
• FIGS. 3 and 4 are diagrammatic sections of two embodiments of a device according to the present invention, comprising, in addition to the means already illustrated in FIGS. 1 and 2, means for filling the container with products, for example rigid, directly in the enclosure surrounding the container at the sealing station;
• FIGS. 5 to 10 illustrate several embodiments of the means allowing the running of an excess length of lidding film in the enclosure of a device according to FIG. 3.

According to FIGS. 1 and 2, the sealing device (1) of a machine for packaging products, in particular food products, in thermoformed trays intended to be capped with a film (11), this device forming part of a thermoformeuse-traerculeuse, comprises a lower portion (2) shaped bowl, intended to receive a tray (4) and lined with a seal (18) on its upper edge, and d 'a part fixed upper (3) bell-shaped, comprising a frame (8) integral with a support plate and surrounding a welding head (9) movable for welding the film (11) on the rim of the tray (4) .

The frame (8) of the upper part (3) of the welding device is traversed at its wall located on the supply side of the lidding film (11) by a slot (13) in which the film passes (11). ). At the slot (13) there is associated a shut-off and locking means (14) with controlled actuation, constituted for example by an inflatable rubber hose, mounted in a hole (16) opening into the slot (13) so that the hose (14, when inflated, blocks the lidding film (11) in the slot (13) and closes the latter in a completely sealed manner.

The frame (8) further comprises, in the same wall, between the slot (13) and the lower edge of this wall, one or more orifices or nozzles (17, for example gas extraction or injection, opening inside the enclosure (25) delimited between the two parts (1) and (2) or the frame (8).

The filling and sealing device as illustrated by FIGS. 3 and 4, which incorporates all the characteristics of the device according to FIGS. 1 and 2, furthermore comprises orifices or nozzles (17) which by their size (section) reduced can only be used for the extraction and / or injection of gas and / or the introduction of more or less fluid products, at least one orifice or nozzle (17A) of larger size (section) designed to allow the passage of all products and especially more consistent products, solid, rigid or pieces.

These orifices (17A) larger, which may have sections and various shapes depending on the products that must be introduced through them in the tray (4) enclosed in the enclosure (25) and can be made of all kinds of various materials, such as, among others, aluminum, stainless steel, plastic etc., depending on the applications and the products to be packaged, can be advantageously completed, to allow the best routing and respect of the products to the sealing station (in the enclosure 25), by means of manual introduction and filling or preferably automated sas type, for introducing the products (26) in the enclosure (25) and deposit them in the tray (4) without altering the controlled atmosphere prevailing in the enclosure (25). These introduction and filling means may in particular comprise mobile transfer means (20), such as carriages in the form of shuttles, mounted for example pivotally, pivotally or not, and mobile way in-and- is in axial translation, under the action of jacks or similar motor means, in guides (23) for example tubular, which can be provided with openings (24) for loading the products in the shuttles (20) since the outside of the packaging machine. It should be noted that according to Figures 3 and 4, the guides (23) for the shuttles (20) may comprise in one or more places means (22) of modified or controlled atmosphere, independent and / or individual and / or centralized, and the shuttles (20) in which the products (26) are advantageously supported by means such that grids may comprise seals (21) ensuring a perfect seal shuttles in the guides, which allows to introduce the products (26) under a perfectly controlled atmosphere, through the orifices or nozzles (17A), in the enclosure (25) and in the trays (4), without disturbing the controlled atmosphere already created in the enclosure and therefore in the trays through orifices or nozzles (17) for fluids.

In the embodiment according to FIG. 3, an orifice (17A) formed in the frame (8) is recognized on the same side as the film passing slot (13) (11), at a distance above the lower edge. the frame, therefore between said lower edge and the slot (13) for passage of the film (11), and more precisely between said lower edge and the orifice or nozzle (17) for fluid.

In the embodiment according to Figure 4, the orifice (17A) for the introduction of the product to be packaged in the tray (4) is instead constituted by a notch which is formed in the lower edge of the frame (8). This orifice (17A) therefore comes to be located, when the sealing device (1) is closed around a tray (4), by the rise of the lower part (2) movable vertically against the fixed upper part (3), directly on the connecting portion between two trays ( 4) successive.

It is clear that in the embodiments illustrated in FIGS. 3 and 4, the filling and lidding device (1) as a whole and more specifically the frame (8) of the upper part (2) is clearly higher. that in the case of the embodiment according to Figures 1 and 2, due to the presence of the orifice (17A) below the slot (13) for passage of the film (11), this slot (13) being thus also located much higher, especially with respect to the tray (4) to be sealed with the film (11). Therefore, the film (11) which remains always attached to the last tray (4) previously capped and which is normally brought into the enclosure (25) under the effect of the only traction exerted by this tray, during the advancement one step of the latter out of the enclosure, as is usual, would follow in the enclosure (25) a more or less oblique trajectory according to the height of the outlet of the slot (13) relative to the upper edge of the tray (4). The descent of the welding head (9) on the tray (4), after blocking of the film (11) in the slot (13) by means (14), would thus cause tearing of the sealing film (11).

To prevent such a tearing of the film (11), the filling and sealing device (1) further comprises means for the inward movement of the enclosure (25) through the slot (13) and the accumulating an excess length of film (11, this excess film length being restored during the descent of the welding head (9) on the tray (4) or similar container.

This scrolling of an excess length of film can, in the context of the invention, be carried out in various ways, for example by mechanical means, electrical, pneumatic, motorized, by pressure, suction, air blowing, etc.

A possibility that is not represented thus consists in controlling the advancement system of the carrier that is scrolling step by step the trays (4) on the packaging machine and thus through the sealing device, so that the progress is made with steps longer than the length of the trays, each step of advancement followed by a recoil stroke corresponding to a fraction of the advancement step. Since the lidding film remains in a manner known per se connected to the pre-capped tray and is thus pulled by this tray into the enclosure (25) still open, the length of film (11) pulled at each step of advancement in the enclosure (25) through the slot (13) is greater than the length necessary to cover the tray in the plane of the upper opening of the latter, the excess film length being, after closing the slot and therefore blocking of the film on the side supplied by the means (14), restored by the back stroke of the previously sealed tray.

According to Figures 5 and 6, the welding head (9) comprises, on the side of the slot (13), a push rod (27) horizontal mounted by springs (28) on the head (9). To bring an excess length of film (11) in the enclosure (25), after advancement of a new tray (4) in the enclosure, but before blocking the film (11) in the slot (13) by the means of closing and blocking (14), the welding head (9) is lowered with the pusher (27) from the upper position according to FIG. 5 to the lower position on the tray (4), according to FIG. then the film (11) in the slot (13) and the head is raised (9) by simultaneously sucking the film (11) upwards, to allow the filling of the tray using the means (17A, 20) sketched only, located below the slot (13).

According to FIG. 7, the upper part (3) of the lidding device (1) comprises a system (29) of positive or controlled advancement acting on the film (11) at the slot (13), for example in downstream of the closing and blocking means (14). It may be in particular a stepper motor or encoder system for bringing into the enclosure (25) a perfectly defined excess length of film (11) before blocking the latter in the slot (13) by means (14).

According to Figure 8, the frame (8) of the upper part (3) of the filling and sealing device (1) has below the filling orifice (17A), at its lowest point, in the vicinity above its lower edge, on the same side as the slot (13), a network of suction openings (30) which, after advancing out of the enclosure (25) of the tray (4), previously sealed, to exert a pull down on the film (11) contained in the enclosure (25) but not yet locked in the slot (13) by the means (14), to thereby bring an excess film length in the enclosure.

According to FIGS. 9 and 10, a horizontal roller (31) is disposed between the welding head (9) and the wall of the frame (8) through which the slot (13) passes, this roller being able to either be mounted on the head of welding (9) and be movable with the latter, like the pusher of Figures 5 and 6, be independent of the welding head (9) and then be controlled separately from the head, for example by one or cylinders mounted (s) ) on the upper part (3), of which only the vertical axis 32 is sketched in the figures.

FIGS. 9 and 10 also show the positive advancement system (29) already described with reference to FIG. 7, which is used here in combination with the tensioning roller (31).

Similarly, it is possible to combine on a filling and sealing device (1) at least two of the various scrolling systems as described and illustrated to bring an excess length of sealing film (11) in the enclosure (25), in order to allow sealing of the trays without risk of tearing the film due to the introduction of the latter by a slot (13) raised relative to the tray (4) due to the presence of the orifice filler (17A) located below the slot (13).

Claims (15)

1. Device for filling and covering packages with a lid for a machine for packaging in a controlled atmosphere products in vessels such as punnets, pots and similar packages to be sealed with a film, comprising a fixed lid-forming upper part (3), provided with a vertically mobile welding head (9), and a vertically mobile tank-forming lower part (2), the lower part receiving at least one vessel (4) to be sealed and cooperating with the upper part so as to define, around the vessel to be sealed, an enclosure (25) in which continuous sealing film (11) previously led through an opening (13) provided in the enclosure (25) above the vessel disposed inside the enclosure, is welded to the vessel by the welding head of the upper part, means being provided to block said opening and immobilize the sealing film, and to obtain a controlled atmosphere inside the enclosure, characterized in that it also comprises introduction and filling means (17A, 20, 23) opening into the interior of the enclosure (25) below said sealing film (11) to introduce into said enclosure (25) products (26) to be packaged and to fill the vessel (4) contained in said enclosure, before the sealing film (11) is welded onto the vessel (4), and sealing film dereeling means for leading in and accumulating an excess length of sealing film inside the enclosure and recovering the excess length when the welding head is lowered onto the vessel to be sealed.
2. Device according to Claim 1, characterized in that the opening for leading the sealing film into the enclosure is a slot (13) provided in the manner of a window in the upper part (3) at a distance above the lower edge of the latter.
3. Device according to Claim 2, characterized in that it comprises controlled actuation blocking and immobilizing means (14) for blocking said slot and immobilizing the film relative to the upper part.
4. Device according to any one of Claims 1 to 3, characterized in that it comprises fluid introduction and/or extraction means (17) opening into the enclosure between the sealing film lead-in opening (13) and the introduction and filling means (17A, 20, 23).
5. Device according to any one of Claims 1 to 4, characterized in that said introduction and filling means (17A, 20, 23) comprise airlock type transfer means (20), enabling products to be introduced into said enclosure without disturbing the atmosphere in the latter.
6. Device according to Claim 5, characterized in that said transfer means comprise at least one shuttle (20) that moves in a sealed manner in a guide (23).
7. Device according to Claim 6, characterized in that said shuttle (20) tilts and swivels.
8. Device according to Claim 6 or 7, characterized in that said guide (23) comprises at least one opening (24) for loading the product (26) into said shuttle (20).
9. Device according to any one of Claims 6 to 8, characterized in that said guide (23) comprises modified or controlled atmosphere application means (22), independent and/or individual and/or centralized, disposed in one or more positions.
10. Device according to any one of the preceding claims, characterized in that the film dereeling means comprise a step-mode conveyor for the vessels, controlled so that the feed is performed with length steps greater than the length of the vessels, each feed step being followed by a retraction length corresponding to a fraction of the feed step.
11. Device according to any one of Claims 1 to 9, characterized in that the film dereeling means comprise an actuator (27) or a roll (31) which is disposed between the welding head (9) and the wall (8) of the upper part (3), on the film lead-in side, and which moves vertically.
12. Device according to Claim 11, characterized in that the actuator or roll is mounted on the welding head (9).
13. Device according to Claim 11, characterized in that the actuator or roll moves vertically under the action of an operating means such as a thruster.
14. Device according to any one of the preceding claims, characterized in that the film dereeling means comprise a positive feed system (29) acting on the film at the film lead-in opening (13) to lead in a perfectly defined excess length of film into the enclosure.
15. Device according to any one of the preceding claims, characterized in that the film dereeling means comprise an array of suction orifices (30) located on the upper part (3) of the device, on the same side as the film lead-in opening (13), below the introduction and filling means (17A, 20, 23).

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