WO2011104679A1

WO2011104679A1 - Sealing insert for use with metallic screw caps for containers

Info

Publication number: WO2011104679A1
Application number: PCT/IB2011/050769
Authority: WO
Inventors: Michele Cervellati; Antonino Pepe
Original assignee: Pelliconi and C SpA
Current assignee: Pelliconi and C SpA
Priority date: 2010-02-26
Filing date: 2011-02-24
Publication date: 2011-09-01
Anticipated expiration: 2012-08-26
Also published as: ES2404907T3; PT2454165E; EP2454165A1; IT1398242B1; EP2454165B1; ITBO20100116A1

Abstract

A sealing insert (1) for use with metallic screw closure caps (3) of bottles (4) comprises: an inner face (9) with a first surface (12) designed to sealingly abut a mouth (8) of a bottle (4) and a second surface (13), opposite the first surface (12), a portion (10) that is prominent relative to the first surface (12) of the inner face (9) and designed to undergo elastic deformation, the prominent portion (10) being located on the periphery (11) of the inner face (9); the prominent portion (10) comprising an inside surface (16) and an outside surface (17) which are substantially inclined outwardly relative to the first surface (12) of the inner face (9), and a convex surface (19) designed to connect the inside surface (16) and the outside surface (17).

Description

Sealing insert for use with metallic screw caps for containers

Technical Field

This invention relates to a sealing insert for use with caps for containers with threaded necks.

More specifically, the invention addresses a sealing insert for use with metallic and aluminium screw caps for glass bottles with threaded necks.

Caps of this kind comprise a housing into which a sealing insert is inserted.

Background Art

The sealing insert is designed to seal the mouth of the bottle when the cap is applied to the threaded neck of the bottle and must guarantee a sealed closure even when the bottle contains a liquid under pressure.

In that sense, the sealing insert constitutes a compliant interface between the mouth of the container and the closure cap and is able to adapt to the surface roughness of the bottle mouth.

Several different types of sealing insert for metallic bottle caps are known.

One disadvantage of prior art sealing inserts is that these sealing inserts are frequently damaged during the bottle capping process during which they are subjected to high mechanical stresses.

During capping, the metallic cap is forced on the threaded bottle neck and plastically deformed in such a way as to create a profile shaped to match that of the thread on the bottle neck; if the insert is not optimally shaped, a large number of closure caps, during the capping process, are damaged at the end of the fiat zone of the housing in the closure cap, where the cap is deformed by bending to create the starting end of a threaded cylindrical portion.

Further, the profiles of prior art sealing inserts are geometrically rather complex; therefore, these inserts are also rather difficult to manufacture and, as a result, a certain number of the inserts are defective or do not conform with production quality standards.

Patent document DE 196 14 019 in the name of Alcoa describes an insert applicable to a screw cap comprising a base and a portion that is prominent relative to the base. A disadvantage of this insert is that it does not guarantee a sealed closure under certain conditions the container is subjected to (high temperature / pressure).

Patent document DE 198 58 778 in the name of Alcoa describes an improvement to the insert described in patent document DE 196 14 019, comprising a base and a portion that is prominent relative to the base.

The prominent portion comprises enlargements at an end of it and/or one or more internal holes.

This insert also comprises recesses on the periphery of it, whose function is to allow air to be vented from the inside of the container if the pressure in the container is excessively high.

This insert, too, does not therefore allow an optimum seal under conditions of very high pressure inside the container; on the contrary, air is vented from the inside of the container when pressure in the container exceeds predetermined limits.

Disclosure of the Invention

The aim of this invention is therefore to overcome the above mentioned disadvantages by providing a sealing insert for use with metallic screw caps for containers with threaded necks, in particular for bottles, which is simple to manufacture and at once resistant to mechanical stresses and able to guarantee a sealed closure even under very difficult conditions.

According to the invention, this aim is achieved by a sealing insert comprising the technical characteristics described in one or more of the appended claims.

Brief Description of the Drawings

The technical characteristics of the invention, with reference to the above aims, are clearly described in the claims below and its advantages are more apparent from the detailed description which follows, with reference to the accompanying drawings which illustrate a preferred, non-limiting example embodiment of the invention and in which:

- Figure 1 is cross section of a sealing insert according to this invention applied to a closure cap which is not applied to a container;

- Figure 2 is cross section of the sealing insert and of the closure cap of Figure 1 screwed to the container;

- Figure 3 is an enlarged cross section of a detail H from Figure 1. Detailed Description of the Preferred Embodiments of the Invention

With reference to the accompanying drawings, the numeral 1 in Figure 1 denotes the sealing insert according to the invention, inserted in a cylindrical housing 2 of a respective screw closure cap 3 of a container 4.

The sealing insert 1 is symmetrical about an axis and, for simplicity, only the left half of it is illustrated in Figures 1 and 2.

The closure cap 3 comprises a metallic body 25, preferably of aluminium, which has the housing 2 made in it.

The cylindrical housing 2 of the closure cap 3 is delimited by a top inner surface 6 and a by a lateral surface 7.

The closure cap 3 will hereinafter be referred to as cap 3.

In Figures 1 and 2, only half of the cap 3, too, is shown, in a configuration where it is not applied to a bottle 4 and in a configuration where it is applied to the bottle, respectively.

The cap 3 is of the screw type and is therefore suitable for closing bottles 4 of the type with externally threaded neck.

The bottle 4, again only half of which - and limited to the part where the cap 3 is applied to it - is illustrated in Figures 1 and 2, comprises an externally threaded neck 5 and a mouth 8 designed to be sealingly closed by the cap 3.

According to the invention, the sealing insert 1 comprises an inner face 9 and a portion 10 which is prominent relative to the inner face 9 and which is located on the periphery 11 of the inner face 9.

The inner face 9 comprises a first surface 12, designed to abut the mouth 8 of the bottle 4 to sealingly close the bottle 4, and a second surface 13, opposite the first surface 12 and designed to abut the top inner surface 6 of the cylindrical housing 2 of the cap 3.

The prominent portion 10 protrudes from the first surface 12 of the inner face 9.

The inner face 9 comprises, preferably but not necessarily, a circular central portion 15 and an annular peripheral portion 14 substantially larger in thickness than the central portion 15. Preferably, the prominent portion 10 is located on the periphery of the peripheral portion 14 of the inner face 9.

The prominent portion 10 comprises an inside surface 16 and an outside surface 17 substantially inclined outwardly relative to the first surface 12 of the inner face 9.

The expression "inclined outwardly relative to the first surface 12 of the inner face 9" means that the tangents to the inside surface 16 and to the outside surface 17 make with the first surface 12 of the inner face 9 a substantially acute angle.

With reference to Figure 1, the inside surface 16 is proximal to the inner face 9, whilst the outside surface 17 is distal from the inner face 9.

The prominent portion 10 further comprises a convex surface 19 designed to connect the inside surface 16 and the outside surface 17.

Preferably, as illustrated in Figure 3, the convex surface 19 comprises arc portions.

The inside surface 16 and the outside surface 17 of the prominent portion 10 are inclined to the first surface 12 of the inner face 9 in such a way that at least a part 20 of the prominent portion 10 is tapered away from the inner face 9, that is to say, in a substantially inclined direction away from the inner face 9 outwardly and downwardly, with reference to Figure 3.

In other words, the inside surface 16 and the outside surface 17 are shaped in such a way that the entire prominent portion 10 is tapered away from the inner face 9; thereby advantageously guaranteeing an optimum seal on the neck of the bottle.

In light of this, it should be observed that the prominent portion 10, extending away from the inner face 9, does not have any enlarged or narrow portion (that is to say, its taper is such that its cross section decreases constantly with extension away from the inner face).

It should be noted that, surprisingly, the shape of the insert is especially suitable for allowing the cap to guarantee a sealed closure even when the pressure inside the container is very high.

The fact that the whole of the insert is tapered away from the inner face allows the insert to undergo deformation when it is pressed into place, thereby guaranteeing an optimum seal.

It should also be noted that the special shape of the prominent portion 10, with an inside surface 16, an outside surface 17 and a convex connecting surface 19, besides providing an extremely effective seal, makes the insert manufacturing process quick and easy (since the insert does require any undercut portions and/or post processing features such as holes).

Preferably, the inside surface 16 and the outside surface 17 make an acute angle a.

More preferably, the angle a is less than 40 sexagesimal degrees. Further, the inside surface 16 is preferably inclined relative to the first surface 12 of the inner face 9 at an angle β substantially less than 35 sexagesimal degrees.

The outside surface 17 comprises a stretch 24 which is substantially perpendicular to the first surface 12 of the inner face 9 for connection to the second surface 13 of the inner face 9.

The outside surface 17 and the inside surface 16 are substantially concave relative to a radial direction away from the inner face.

The sealing insert 1 is made preferably as a single part.

Preferably, the sealing insert 1 is made from a polymer, chosen from the group including PP (polypropylene), PE (polyethylene) and composites thereof, or from PVC (polyvinyl chloride).

The sealing insert 1 is made preferably with a punch die comprising a cavity which is shaped to match the insert.

Advantageously, the profile of the sealing insert 1 can be made very easily on an industrial scale since it has straight and arcuate portions and, in geometrical terms, is relatively simple to construct.

A comparison of Figure 1, where the cap 3 is not applied to the neck 5 of the bottle 4, with Figure 2, where the cap 3 is applied to the neck 5 of the bottle 4, clearly shows the deformation which the sealing insert 1 undergoes when the cap 3 is applied to the neck 5 of the bottle 4 to close the mouth 8 of the latter.

In effect, during the capping process, the cap 3 becomes deformed in such a way that the profile of the metallic body 25 becomes shaped to substantially match the shape of the threading on the neck 5 of the bottle 4 and the prominent portion 10 undergoes deformation as a result of the compressive action applied to it by the outside surface 21 of the neck 5 of the bottle 4 and by the lateral surface 7 of the cylindrical housing 2 of the cap 3.

Thus, as shown in Figure 2, when the cap 3 is applied to the neck 5 of the bottle 4, the outside surface 17 of the prominent portion 10 adheres to the lateral surface 7 of the cylindrical housing 2, while the inside surface of the prominent portion 0 adheres to the outside surface 21 of the neck 5 of the bottle 4.

The prominent portion 10 makes it possible to reduce mechanical deformations on the cap 3 and on the bottle 4 during the capping process; when the cap 3 is applied to the bottle, the prominent portion 10 is elastically deformed and thereby makes it possible to reduce the deformation of the cap 3 at the end zone of the flat surface of the top inner surface 6 of the inner face 9 of the cylindrical housing 2. The prominent portion 10, when the cap 3 is applied to the bottle 4, forms an enlarged end portion 22 which allows deformation of the cap 3 to be further reduced during the capping process.

The enlarged end portion 22 also acts as a damping element interposed between the cap 3 and the bottle 4.

Advantageously, the prominent portion 10 prevents damage to the sealing insert 1 at the flat end zone of the top inner surface 6 of the inner face of the cylindrical housing 2 of the cap 3 when the cap 3 is applied to the bottle 4.

Further, advantageously, a portion of the inside surface 16 of the prominent portion 10 adheres to the top surface 23 of the mouth 8 of the bottle 4; this guarantees a sealed closure of the mouth 8 of the bottle 4 even in the presence of liquid under pressure.

An advantage of this invention is that it makes available a sealing insert for use with metallic screw caps of containers, in particular bottles, which is simple to manufacture and at the same time resistant to mechanical stresses, especially those applied during the capping process.

Thanks to its special shape, the sealing insert guarantees a sealed bottle closure even in the presence of liquid under pressure (or even in the presence of mechanical stresses).

It should be noted that, preferably, the prominent portion of the insert does not have recesses, holes or enlarged portions; according to this aspect, the prominent portion is an unbroken portion of material, that is to say, one without cavities and/or holes in it.

This guarantees optimum deformation and allows the closure to remain effectively sealed even under very difficult conditions.

It should also be noted that the prominent portion 10 extends annularly around the inner face 9 uninterruptedly, that is to say, without any break in it (that is to say, the prominent portion 10 surrounds the entire peripheral edge of the inner face 9); that guarantees a perfectly sealed closure in any zone of the container.

In effect it should be noted that this solution guarantees sealed closure even under very difficult conditions all around the edge of the bottle neck (unlike some prior art solutions, such as, for example, the one described in DE 198 58 778, which contemplated air venting when the pressure inside the container exceeded certain limits).

The invention described above is susceptible of industrial application and may be modified and adapted in several ways without thereby departing from the scope of the inventive concept. Moreover, all the details of the invention may be substituted by technically equivalent elements.

Claims

1. A sealing insert (1) for use with metallic screw closure caps (3) of bottles (4) comprising

- an inner face (9) with a first surface (12) designed to sealingly abut a mouth (8) of a bottle (4) and a second surface (13), opposite the first surface (12),

- a portion (10) that is prominent relative to the first surface (12) of the inner face (9) and designed to undergo elastic deformation, the prominent portion (10) being located on the periphery (11) of the inner face (9), the insert being characterized in that the prominent portion (10) comprises an inside surface (16) and an outside surface (17) which are substantially inclined outwardly relative to the first surface (12) of the inner face (9), and a convex surface (19) designed to connect the inside surface (16) and the outside surface (17), the inside surface (16) and the outside surface (17) being shaped in such a way that the entire prominent portion (10) is tapered away from the inner face (9).

2. The sealing insert according to claim 1, characterized in that the inside surface (16) and the outside surface (17) make an acute angle (a).

3. The sealing insert according to claim 2, characterized in that the acute angle (a) is less than 40 sexagesimal degrees.

4. The sealing insert according to claim 2 or 3, characterized in that the inside surface (16) is inclined relative to the first surface (12) of the inner face (9) at an angle substantially less than 35 sexagesimal degrees.

5. The sealing insert according to any of the claims from 1 to 4, characterized in that the inside surface (16) and the outside surface (17) are substantially concave towards the outside.

6. The sealing insert according to any of the claims from 1 to 5, characterized in that the convex surface (19) comprises arc portions.

7. The sealing insert according to any of the claims from 1 to 6, characterized in that the outside surface (17) comprises a stretch (24) which is substantially peipendiciilar to the first surface (12) of the inner face (9) for connection to the second surface (13) of the inner face.

8. The sealing insert according to any of the claims from 1 to 7, characterized in that the inner face (9) comprises a circular central portion (15) and an annular peripheral portion (14) larger in thickness than the central portion (15); the prominent portion (10) being located on the periphery of the annular peripheral portion (14).

9. The sealing insert according to any of the claims from 1 to 8, characterized in that the inner face (9) and the prominent portion (10) are made from a polymer or PVC.

10. A closure cap (3) for bottles characterized in that it comprises a metallic body (25) provided with a cylindrical housing (2) and a sealing insert (1) according to any of the claims from 1 to 9 insertable in the cylindrical housing (2) of the metallic body (25).