Technical Field The invention relates to a capsule for closing containers. In particular reference is made to a capsule of the type described in the accompanying first claim.

Background Art Publication EP 0 909 715 teaches a capsule of the above-mentioned type. The present invention proposes to improve the sealing characteristics of capsules of this type.

An advantage of the invention is that it guarantees hygiene during container use.

A further advantage of the invention is that it provides a capsule which can be provided with a security device against attempts at intrusion through the outlet mouth of the first cap.

A further advantage of the invention is that it provides a capsule for containers of dangerous liquid products which is provided with a security device preventing opening thereof by children.

A further advantage of the invention is that it provides an excellently-sealed capsule for closing containers of gassy liquids.

These aims and advantages and more besides are all attained by the present invention, as it is characterised in the appended claims.

Further characteristics and advantages of the present invention will better emerge from the detailed description that follows, of two preferred but not exclusive embodiments thereof, illustrated purely by way of non-limiting example in the accompanying figures, in which:

figure 1 is a section view of a first embodiment of the capsule of the invention ; figure 2 is a view from above of figure 1 ; figure 3 is the capsule of figure 1 in an open configuration; figure 4 shows a second embodiment of the invention; figure 5 is the capsule of figure 4 in an open configuration.

Disclosure of Invention With reference to the figures of the drawings from figure 1 to figure 3,1 denotes in its entirety a capsule for closing a container, in particular a container for gassy liquids.

The capsule 1 comprises a first cap 2 destined to be constrained, by a screw connection, to a mouth 3 of the container 1, while being able to make axial raising and lowering movements with respect to the container 1.

The first cap 2 exhibits a cylindrical first wall, coaxial and external in relation to the mouth 3 of the container 1. The first cap 2 internally bears means for screw- coupling to the container 1. The upper end of the first wall is joined to the periphery of a flat and horizontal second wall located above the upper end of the mouth 3 of the container 1. A tubular third wall starts from an internal edge of the second wall going downwards. The third wall is coaxial and located internally of the mouth 3 of the container 1. The third wall has a free lower end bearing an annular relief 4 which projects laterally externalwise. The third wall superiorly bears an annular seal 15 (in this case made in a single piece with the wall) which seal 15 projects laterally externalwise.

The first wall of the first cap 2 externally exhibits a lateral surface having a polygonal section. In the example the shape is a regular octagon, as can clearly be seen in figure 2. This shape improves the grip of the capsule by a machine which is equipped with a gripping tool of a corresponding shape. Further, thanks to this polygonal shape, a user can see immediately that the container is to be

opened and closed by unscrewing and re-screwing.

A fourth wall starts from the internal edge of the second wall and rises therefrom.

The fourth wall is tubular, coaxial to the container and located above the mouth thereof. The fourth wall has an upper end which bears an annular relief 5 projecting laterally outwards.

The first cap 2 comprises a tubular fifth wall 2a having a free lower end and an upper end which is connected via a horizontal tract of wall to the fourth wall. The fifth wall 2a internally describes a passage for the exit of the liquid from the container 1.

The capsule 1 comprises an annular element 6 housed within the first cap 2 and predisposed to couple with the mouth 3 of the container. At least a part of the annular element 6 is destined to separate from the first cap 2 on the first opening of the capsule 1 by effect of the rupture of the easy-break ribs 7 which, in the embodiment described, are predisposed on the annular element 6, which is thus divided into two parts: a lower part, destined to detach, and an upper part, which remains jointed in the first cap 2 even after the first opening of the capsule 1.

The capsule 1 further comprises an obturator 8 inserted into the container mouth.

Before assembling the capsule 1, the obturator 8 is coaxially connected to the annular element 6 by easy-break ribs, so that it is detachable therefrom when the obturator 8 is coupled with the rest of the capsule.

The obturator 8 is provided with a tubular first external wall, internal and coaxial to the mouth, having an upper end which externally bears an annular lateral projection, which is interpositioned between the first cap 2 and the upper end of the mouth 3. The first wall of the obturator 8 exhibits an external lateral surface which seals against the inside of the mouth 8, and an internal lateral surface which bears three annular reliefs projecting laterally towards the inside, arranged at three different distances one from another, the function of which will be better

clarified herein below.

The three reliefs 9 have progressively increasing internal diameters, starting from the upper relief going down to the lower relief. The upper relief 9 has an internal diameter which is smaller than the external diameter of the annular seal 15 of the first cap 2.

A peripheral part of a second wall is located at the lower end of the first wall of the obturator 8. This part of the second wall is flat and horizontal and in the shape of a circular crown, provided with at least one opening 10 for the exit of the liquid from the container. A third wall starts from the internal edge of the second wall; this third wall has a tubular shape and is closed at the top thereof.

The first cap 2 can selectively assume at least one lower position, a closed position (see figure 1) in which the central exit passage of the liquid is closed by the upper part of the third wall of the obturator 8, and at least an upper position, an open position (see figure 3), in which the exit passage is unobstructed. In the closed lower position, the internal surface of the fifth wall 2a of the first cap 2 seals against the external surface of the third wall of the obturator 8. Further, in the closed lower position the seal 15 closes and seals against the upper relief 9.

In the open upper position the lower part of the annular element 6 is detached.

The capsule 1 comprises a second cap 11, external of the first cap 2, which provides further protection. The second cap 11 is internally provided with a projection 12 coupled with the first cap 2.

In the embodiment of figure 1, the above-mentioned projection 12 of the second cap 11 is placed on an easy-break security ring, which is in fact the lower end of the second cap 11, destined to be broken by effect of a raising of the second cap 11 from the first cap 2.

The second cap 11 exhibits a first lateral wall, which is in effect a coaxial jacket to the first cap 2. The security ring is connected inferiorly to this first lateral wall.

At the top of the first lateral wall there is a second wall which is flat and horizontal and which covers the exit passage afforded by the first cap 2. An annular relief element 13 projects axially downwards from the inside of the second wall. The relief element 13 has a cylindrical internal annular surface, of a predetermined internal diameter, which works together with the annular relief 5 laterally projecting from the third wall of the first cap 2, and thus creates a seal which insulates the central zone of the capsule (where the exit passage of the first cap 2 is afforded) from the outside environment.

The annular reliefs 9 located on the first wall of the obturator 8 are predisposed to interact with the externally-projecting annular relief 4 of the third wall of the first cap 2. Each annular relief 9 of the obturator determines a resistance to raising of the first cap 2. The lower annular relief 9, having the largest diameter of all three, in particular serves to give a certain stability to the lower position of the first cap 2 after cap assembly and before application of the capsule on the container. The intermediate annular relief 9 serves in particular as a warning stop to the user, informing him or her that a first open position has been reached at which the capsule is effectively open and liquid can be obtained from inside the container. In this position the first cap 2 is still screwed onto the mouth 3.

By continuing to unscrew the first cap 2, with a small effort to cause the relief 4 to overcome the intermediate relief 9, the first cap 2 is brought into a second open position, defined by the upper third relief 9, in which it is completely unscrewed from the mouth 3. In this position, even though the screw-coupling is completely unscrewed, the first cap 2 is still coupled to the obturator 8. Complete freeing of the mouth 3 upper opening can be obtained by making a further axial raising movement of the first cap 2, which, thanks to the coupling between the relief 4 and the upper relief 9, draws the obturator 8 upwards with it.

In use, the user first removes the second cap 11 (which has served to guarantee

the security of the package and contents) and then, to reach the product inside, unscrews the first cap 2 up to the first open position. If the user continues to unscrew, the first cap 2 exits from the screw coupling, moving into the second open position, in which an unscrewing rotation does not lead to a raising of the first cap 2. In both open positions, the liquid product can be obtained without removing the first cap. The first cap can therefore subsequently be rescrewed, to close the container.

The closed capsule is guaranteed airtight by various seals: the fifth wall 2a of the first cap 2 coupled sealedly to the third wall of the obturator 8, the annular seal 15 of the first cap 2 which seals against the upper relief 9 of the obturator 8, the annular relief 13 of the second cap 11, coupled sealedly with the relief 5 of the obturator 8.

Looking now at the second embodiment of the capsule, illustrated in figures 4 and 5, the elements which are effectively the same as in figures from 1 to 3 are denoted using the same numbers. This capsule can be usefully applied on containers for dangerous liquids which must therefore be childproof.

The second cap 11 comprises a first external lateral wall, in the form of a jacket, joined to a flat second wall, at the centre of which an opening is afforded for exit of liquid from the container, which opening faces an outlet mouth afforded at the centre of the first cap 2.

The first wall of the second cap 11 laterally covers the entire first cap 2 and the part of the annular element 6 destined to stay constrained on the first cap 2 after the container is first opened.

The capsule is provided with a childproof security device 14, which is activated by effect of a pressure on the second cap 11, to make the first cap 2 and the second cap 11 reciprocally solid in unscrewing rotation. This device comprises two crowns exhibiting radial teeth, the teeth facing each other and being arranged

circumferentially on the two caps 2 and 11.

It can be seen that in the second embodiment, differently to the first, the first cap 2 does not exhibit a polygonal external surface which can aid the operator to understand that the capsule opening method is of the screw-type.

In use, to open the capsule the second cap 11 must be pressed downwards to activate the security device 14, and then, while maintaining the downwards pressure; then the two caps 2 and 11 are rotated together in the unscrewing direction of the first cap 2.