It is well known to the experts of the branch and the operators of the bottling industry that in the filling plants for liquid foodstuffs like wine, mineral water, etc. the individual glass containers, such as bottles, jars etc. must be conveyed to the filling unit in a suitable hygienic and sterile condition, free of any internal foreign matter.

It is equally known that the glass containers are, after leaving the oven and subjecting to the necessary controls, positioned on pallets or flatbeds for their packing in multi-layered groups. The containers have an open mouth before packing and/or wrapping in plastic or simply covering with a resting surface for other containers to piled up upon them, and may thus be receptive to any kind of impurity.

Precisely because of this need, it has been attempted to close the mouth of each bottle or container with a cap or similar, to be later thermally welded or shrunk in place.

Such an operation on each bottle carries a certain cost, both for the emplacement and the difficult removal

before the subsequent bottling phase, in addition to the costs of producing the individual cap or cover.

Attempts have also been reported to close the mouth by a section of plastic film, for instance made of polyethylene, polypropylene or the like, so as to impede the access of any contaminating matter to the inside of the container, thus preserving its sterility and cleanliness.

The potential emplacement of a section of plastic film, which is at any rate feasible only when the glass container is hot, would allow a sealed closing of the container, but not offer a high degree of stability. The plastic material exhibits an undoubted compliance and may happen to be removed, albeit accidentally, thus failing to ensure the containers'cleanliness and sterility.

It can also be assumed that the thinness of said film could favor an interference or friction between the various glass containers, to the point of causing them to rupture or to dent part of the same.

The purpose of this invention is to create a tight seal capable of being firmly maintained at the mouth of the glass container or bottle, immediately after being produced in the glassworks, or shortly after their exiting the tunnel.

Another purpose is to create a seal capable of resolving the cleanliness problems mentioned above,

while also allowing the glass containers to be piled up without any drawbacks.

These purposes according to this invention are achieved by producing a tight sealing device at the mouth of a container to be filled with liquid foodstuffs, as outlined in claim 1.

Additional features are outlined in further claims.

The characteristics and advantages of a device according to this invention will become more clearly evident from the following description, offered for exemplifying and non-limiting purposes, with reference to the simplified attached drawings, in which: Figure 1 is an upper plan view of a device according to the invention, capable of being emplaced at the mouth of a glass container, Figure 2 shows an enlarged cross-section of the device of Figure 1.

Figure 3 shows an upper portion of a glass bottle fitted with the device according to this invention.

The figures referred to show a tight sealing device for the mouth of a glass container for liquid foodstuffs, produced according to this invention and placed on the mouth 10 of a container 11, in the form of a glass bottle in the example shown.

In particular, the device of this invention is placed on the mouth and inserted with a minimum forcing action, in a step practically following that of the

glass container's annealing phase, directly at the glassworks. In this phase the interior of the container 11 is in fact still clean (almost sterile) and perfectly hygienic, so as to be suitable for receiving a liquid foodstuff such as wine, mineral water, etc.

As shown in a brief example in Figure 3, it is necessary to provide a manipulator (12), such as a suction cup, capable of picking up an operculum 13 from a storage space (not shown) and placing it on the mouth 10 to form a stable seal of its interior.

This can be done by a simple mechanical operation, if effected immediately after the annealing phase favored by the hot glass, which even creates a depression inside the container. If the glass were to be cold, it would be seen that the operculum 13 snaps in by a slight pressure.

The Figures 1 and 2 show how to produce this operculum (13), which provides the tight seal at the mouth of a container for liquid foodstuffs.

The operculum 13 is produced by molding it from a virgin, non-recycled food-grade polyethylene material in a first-time use.

It can be seen that the same operculum 13 provides for a peripheral portion 14 with a cuff 15 covering the upper external area of the mouth 10.

A hollow central portion is then extended from this peripheral portion (14), which sags toward the interior and can be inserted in the mouth 10 of the container 11.

This hollow portion comprises a central wall 16 connected to the peripheral portion (14) by a tubular section 17. An annular profile (18) is defined in the annular connecting area between the central wall 16 and the tubular portion 17, having a V-shaped section projecting toward the outside of the central wall 16, opposite to the hollow portion.

This annular profile 18 with a V-shaped section is inserted in the mouth 10 of the container 11 and allows, thanks to its partial pliability, a stable positioning of the operculum 13 on the bottle 11.

The peripheral portion 14 provides one or more projections 19 in its interior, on the surface likely to come in contact with the mouth 10. These projections (19) are also designed to improve the stable positioning of the operculum 13 and to enhance the tight sealing toward the outside.

Such an arrangement can ensure a perfectly tight seal of the inside of the container or bottle 11, so as to preserve it in a hygienic and clean condition during the transition between the production of the container and its filling with liquid.

It can also advantageously be noted that thanks to the material constituting said operculum 13, the same

also has a certain consistency that keeps it in position within the mouth 10 of the container or bottle 11.

This maintains a clean"vacuum"suitable for foodstuffs inside the bottle or container (11).

The peripheral portion 14 fitted with a cuff 15 to cover the upper external area of the mouth 10 also serves to protect the mouth of the container itself, which could suffer a partial or total breakage.

This may happen particularly in the containers' piling-up phase, when the same are packed in the glassworks before forwarding them to the companies filling them with liquid foodstuffs.

The presence of this operculum 13, while protecting against breakages, also allows avoiding the formation of grooves, because it prevents the containers from sliding over each other during the piling-up process.

Despite its stable emplacement on the mouth of the container, an operculum or tight sealing device for the mouth of a container to be filled with liquid foodstuffs according to the invention will also be easily removable.

The stability of the operculum allows using attaching or withdrawing elements capable of exerting a certain force on the operculum itself.

This eliminates all the drawbacks present in the previously mentioned known art.

The prime purpose is as mentioned to safeguard the inside of the container and the safety of the user, above all when the glass container is unpacked and may, albeit accidentally, receive any object or other foreign element.

The operculum 13 is very thin and elastic and may weigh about half a gram for a diameter of 30 mm. It therefore adapts very well to the internal surfaces and the"flush to the mouth"area of the individual glass containers to which it is applied before filling.

This operculum can, if individually profiled, be adopted from a diameter of 8 mm to 35 mm and adapts both to the upper surface of the mouth and to an area of short depth in its interior.

Thanks to its elasticity coupled with a certain stability, the operculum 13 is also capable of compensating the less then perfectly cylindrical roundness of the inside of the container's mouth, thus adapting to the same.

It is therefore clear that the device of this invention is thus capable of resolving the problem of a correct positioning with a tight sterile seal on the mouth of the containers to be conveyed toward the filling heads of liquid foodstuffs.

This product made of virgin polyethylene also safeguards the environment while observing the existing regulations, as it can be fully recycled.

It is important not to confuse this operculum, which produces a temporary closure of the container, with an ordinary cap underside for screw caps, snap-off caps etc., which have different structural characteristics and purposes closely related and dedicated to the final closing of the container.