PLASTIC CAP FOR A CONTAINER Field of the Invention The present. invention relates to a plastic cap for a container, which has an opening portion with an opening formed therein, which cap, for sealing the opening of the container, has a first bendable cap part, which comprises an oxygen-tight liner to be joined to a circular opening end surface around the opening and, for defined mounting on the container, has a circumferential flange, which is arranged to surround the opening portion of the container in a substantially tight-fitting manner, the liner having a first side which is permanently joined to the first cap part and a second side which is arranged to be tempora- rily hermetically sealed to said opening end surface, the flange having a first lifting means, which is arranged to facilitate removal of the cap, and the liner and the first cap part being joined to each other in such a man- ner that the liner accompanies the first cap part when, for removal from the container by said first lifting means, said first cap part is bent away from said opening end surface.

Background Art A plastic cap of the type stated by way of introduc- tion is known from WO 03/068625. This document discloses a very simple and user-friendly snap cap which comprises an oxygen-tight liner of, for instance, aluminium. The liner is permanently joined to the cap and temporarily joined to the associated container preferably by induc- tion welding. The cap is removed from the container by being bent, gripped by the thumb. The opening movement is facilitated by the bending of the cap making the tem- porary joint between the container and the cap be broken gradually. The opened container can then be resealed by snap engagement between the container and the cap, where-

by a smooth opening end surface, provided by the above- mentioned opening movement, of the opened container and a corresponding smooth opposite surface of the liner ensure good tightness.

Object of the Invention It is obvious that sometimes caps are preferred which instead are opened by a turning movement. The prior-art cap is not suited for such a turning movement since its liner at least initially is joined to the con- tainer and thus opposes any turning. If, nevertheless, the cap in such a position should be violently forced to make a turning movement, the liner would be torn and leave an uneven opening end surface on the opened con- tainer.. In resealing, tightness would thus not be obtain- ed, and moreover the uneven opening end surface would be perceived by a user as very annoying, for instance when the container is used as a drinking container to be moved to the user's lips. In view hereof, the object of the invention is to provide a plastic cap according to the preamble, which allows oxygen-tight sealing, opening by a simple turning movement, tight resealing and provision of a smooth opening end surface on the opened container.

Summary of the Invention According to the invention, this object is achieved by an annular second cap part being adapted to surround the opening portion of a container, which second cap part has a second lifting means which is arranged to cooperate with said first lifting means on the flange in such a manner that, when the second cap part is turned for open- ing of the container, the first cap part is bent away from said opening end surface, where during turning the temporary, hermetic seal between the liner and the open- ing end surface of the container is gradually broken.

The solution according to the invention allows oxygen-tight sealing of a container according to the

same principles as the prior-art snap cap according to WO 03/068625. It also allows opening by a simple turning movement, which besides requires a minimum of efforts since the cap during turning is"peeled off"gradually.

In addition, a smooth opening end surface is always pro- vided on the open container, which enables tight reseal- ing and provides good user-friendliness for, for example, a drinking container.

Preferably, the circumferential flange of the first cap part has an inner annular bead to be connected by snap action to a corresponding outer annular notch or bead at the opening portion of a container. This solution implies basically that the first cap part will have an appearance that reminds somewhat of the snap cap accord- ing to WO 03/068625 and also means that the first cap part, if after initial opening of the container it is separated from the associated second cap part, can serve as a traditional snap cap.

According to a first embodiment, the second cap part has an. underside which is adapted to rest on a shoulder on the opening portion of a container. Such an embodiment is usable especially when a container of the type shown in WO 03/068625 is to be provided with an unscrewable cap, but of course does not necessarily require the underside of the cap part and the shoulder of the con- tainer to be positioned in a plane parallel to the radial plane of the turning movement.

In one variant of the first embodiment, the first lifting means comprises at least one ramp surface, directed towards the second cap part, on the flange, and said second lifting means comprises at least one corre- sponding ramp surface directed towards the flange. This variant is extremely simple and is based on the know- ledge that to provide a ramp surface it is sufficient to arrange the plane of the ramp surface in a plane inclined to the radial plane of the turning movement.

In one cap in the first variant, said at least one ramp surface of the first lifting means can be positioned in a recess in the flange, and said at least one ramp surface of the second lifting means is formed on a ridge of the second cap part. In another cap in this first variant, said at least one ramp surface of the first lifting means can be formed on a ridge of the flange and said at least one ramp surface of the second lifting means can be positioned in a recess in the second cap part. These two caps-are advantageous since they are extremely easy to manufacture and distinctly indicate to a user that the opening in progress is successful.

Preferably, the first lifting means of the above- mentioned caps with ramp surfaces comprises exactly two diametrically opposed ramp surfaces and, correspondingly, the second lifting means comprises exactly two dia- metrically opposed ramp surfaces. The advantage of this is that opening of the container can thus be performed by turning the second cap part half a turn only, and that the force required for opening will be moderate since the first cap part during opening only needs to be bent along mutually parallel bending lines which thus do not coun- teract each other.

Preferably, the first and the second cap part are formed integrally with each other and connected to each other by means of a breakable tamper-resistant strand.

In this way a clear indication of an unbroken and broken container, respectively, is allowed, and moreover the handling of the caps is facilitated both in manufacture and in mounting thereof on containers.

In a second embodiment, the first lifting means comprises at least one outwardly directed wing and the second lifting means comprises at least one inner thread, with which said at least one wing is threadingly engaged.

An advantage of this embodiment is that a thus designed cap has a second cap part, which in its mounted state

completely surrounds the outside of the first cap part and, consequently, can be easier for a user to grip.

In a third embodiment, the first lifting. means com- prises at least one outwardly directed wing and the second lifting means comprises an inner annular shoulder, with which said at least one wing is slidingly engaged and which is arranged to be raised in relation to the container by means of an inner thread formed inside the second cap part and engaging an outer thread formed on the container. An advantage of this embodiment is that a thus designed cap has a second cap part, which in its mounted state completely surrounds the outside of the first cap part and, thus, can be easier for a user to grip. Another advantage of this embodiment is that the threaded engagement of the second cap part with the con- tainer enables more reliable resealing.

In the second as well as in the third embodiment, the second cap part suitably has an upper part in the form of an inwardly directed annular flange, in which there is at least one recess for said at least one wing, the first and the second cap part initially being inte- grally formed with said at least one wing positioned in the associated recess, and a connection, which is positioned between the first and the second cap part, being adapted to be broken in connection with mounting of the cap on a container. This solution considerably facilitates the handling of the caps both in manufacture and in mounting thereof on containers.

Preferably, the first lifting means according to the second and the third embodiment comprises exactly two diametrically opposed wings. The advantage of this is, in the same way as mentioned. above, that opening of the con- tainer can thus be performed by turning the second cap part half a turn only and the effort required for opening will be small since the first cap part during opening only needs to be bent about mutually parallel bending lines.

The plastic cap according to the third embodiment has in its variant with an inwardly directed annular flange preferably teeth on the annular flange, which teeth are arranged to be directed towards a container, and on the wings opposite teeth for engaging these teeth, so that the first cap part, on turning the second cap part for resealing of the container, is driven in the turning movement. This is advantageous since it will be considerably easier to place the first cap part on the container for resealing.

Brief Description of the Drawings Preferred embodiments of the plastic cap according to the invention will be described in more detail in the following with reference to the accompanying drawings, in which Fig. 1 is a side view of a first embodiment of a plastic cap in a sealing position on a container; Fig. 2 is a side view of the plastic cap in Fig. 1 in an opening position ; Fig. 3 is a perspective view of a second embodiment of a plastic cap in a position for manufacture or deli- very ; Fig. 4 is a perspective view of merely the first cap part of the plastic cap in Fig. 3; Fig. 5 is a perspective view of merely the second plastic cap part of the plastic cap in Fig. 3; Fig. 6 is a sectional view of the plastic cap in Fig. 3 in a position for manufacture or delivery; Fig. 7 is a sectional view of the plastic cap in Fig. 3 mounted on a container; Fig. 8 is a part-sectional view of a third embodi- ment of a plastic cap in a position for manufacture or delivery; Fig. 9 is a part-sectional view of the plastic cap in Fig. 8 in a sealing position;

Fig. 10 is a bottom view of the plastic cap in Fig. 8; Fig. 11 is a top view of the plastic cap in Fig. 8; and Fig. 12 is a part-sectional view of the plastic cap in Fig. 9 mounted on a container.

Description of Preferred Embodiments A common feature of the plastic caps 1 illustrat- ed in the drawings, for which like reference numerals are used throughout the text to designate equivalent components, is that they are intended for containers 2 which have an opening portion 3 with an opening 4 formed therein (see especially Figs 7 and 12).

To seal the opening 4, the caps 1 have a first bendable cap part 5, which comprises an oxygen-tight liner 6. This is the same type as the one stated in WO 03/068625 and has been integrated in said first cap part 5 in the injection-moulding of the caps 1. The liner 6 has a first side 7 which is permanently joined to the first cap part 5, and a second side 8 which is arranged to be temporarily hermetically sealed to an opening end surface 9 around the opening 4 of the container 2 (see once more Figs 7 and 12).

For defined mounting on the container 2, the plastic caps 1 have a circumferential flange 10, which is arrang- ed to surround the opening portion 3 of the container 2 in a substantially tight-fitting manner. The flange 10 has a first lifting means 11, which depending on the embodiment is of different kinds and which is arranged to facilitate removal of the cap 1 in a manner that will be described in more detail below.

According to the invention, the liner 6 and the first cap part 5 are in the manner known from WO 03/068625 joined to each other so that the liner 6 accompanies the first cap part 5 when this, for removal

from the container 2, is bent away from said opening end surface 9 by said first lifting means 11.

A common feature of all three embodiments described is that this bending away from the opening end surface 9 of the container 2 is performed by means of an annular second cap part 12 which is arranged around the opening portion 3 of the container 2. The second cap part 12 has a second lifting means 13 whose appearance differs depending on the embodiment but which is arranged to cooperate with said first lifting means 11 of the flange 10 so that, when the second cap part 12 is turned to open the container 2, the first cap part 5 is bent away from said opening end surface 9. The fact that the temporary, hermetic seal between the liner 6 and the opening end surface 9 is gradually broken while the second cap part 12 is turned, ensures that the force required for the turning movement will be very limited and that a smooth opening end surface 9 is obtained without any rests being torn off from the liner 6.

In the plastic cap 1 according to the first embodi- ment in Figs 1 and 2, the circumferential flange 10 of the first cap part 5 has, for resealing, an inner annular bead which is concealed in Figs 1 and 2, but is to be compared to the annular beads of the plastic cap disclos- ed in WO 03/068625 and of the plastic cap described below in connection with the second embodiment, and which is arranged to cooperate by snap engagement with a corre- sponding annular notch or (as shown) bead 14 on the con- tainer 2. In addition, the first cap part 5 has a first lifting means 11 in the form of two diametrically opposed ramp-like recesses 15 in the underside of the flange 10 facing the container 2.

In the plastic cap 1 shown in Figs 1 and 2, the annular second cap part 12 has an underside facing the container 2 and adapted to rest on a shoulder 6 on the opening portion 3 of the container 2. The second cap part has a second lifting means 13 which corresponds to the

first lifting means 11 and is in the form of two diame- trically opposed ramp-like ridges 17.

Finally it can be mentioned that the. plastic cap 1 in Figs 1 and 2 is made in one piece and that in the transition between the first and the second cap part 5,12 it has a tamper-resistant strand 18 which can be divided into a plurality of segments and which is broken in connection with initial turning of the second cap part 12 in relation to the first cap part 5 and, after that, thus clearly indicates outwards that a container 2 is broken.

The plastic cap 1 according to the second embodiment as shown in Figs 3-7 is to be found both in a position for manufacture or delivery and in a mounting position.

In the former position, its appearance is the one illu- strated in Figs 3 and 6, in which its first and second cap part 5 and 12, which are made in one piece, are still joined to each other by means of a number of joining strings 19. In the latter position, the joining strings 19 have been broken and the first cap part 5 is pressed down into the second cap part 12 so as to provide the appearance according to Fig. 7.

In the cap 1 in Figs 3-7, the first cap part 5 has, as is to be clearly seen in Figs 6 and 7, an integrated liner 6. This suitably comprises an aluminium foil and is consequently oxygen-tight and can be welded by induction- welding in the same way as preferably the liner according to WO 03/068625 and, for that matter, the liners in the other embodiments described herein. The cap 1 in Figs 3-7 also has two diametrically arranged, projecting wings 20 which form the first lifting means 11 of the first cap part 5. In the position for manufacture or delivery, the wings 20 form a part of an inwardly directed annular flange 21 of the second cap part 12, in which annular flange 21 in the mounting position there are recesses 22 corresponding to the previous position of the wings 20.

Moreover the first cap part 5 also has an inner annular

bead 23 which in engagement with a corresponding notch or (as shown) bead 14 in the container 2 allows resealing thereof by snap engagement.

In the cap in Figs 3-7, the second cap part 12 also has an underside which faces the container 2 and which in the same way as in the first embodiment above is adapted to rest on a shoulder 16 on the opening portion 3 of the container 2 (see Fig. 7). The second cap part 12 has, in addition, threads 24 which are positioned under said inwardly directed annular flange 21 and which, diame- trically opposite each other, in the form of left-hand threads preferably climb half a turn up the inner wall of the second cap part 12. With these threads 24, which in this embodiment constitute the second lifting means 13 of the second cap part 12, the first lifting means 11, thus the two wings 20, of the first cap part 5 is threadingly engaged, and thus is raised in relation to the container 2 when the second cap part 12 is turned counterclockwise to open the container 2.

According to the third, and currently preferred, embodiment of the invention, the plastic cap 1 according to Figs 8-12 has a first cap part 5 with a first lifting means 11 in the form of two diametrically opposed, out- wardly directed wings 20 and a second cap part 12 with a second lifting means 13 in the form of an inner annular shoulder 25, with which the two wings 20 are slidingly engaged. The annular shoulder 25 and, thus, the two wings 20 are raised in relation to the container 2 by means of an inner thread 26 inside the second cap part 12 and an outer thread 27 around the opening portion 3 of the con- tainer 2.

Also the plastic cap 1 illustrated in Figs 8-12 is to be found in a position for manufacture or delivery 'and in a mounting position. In the former position, its appearance is the one illustrated in Fig. 8, in which its first and second cap part 5 and 12, which are formed integrally with each other, are still joined to each

other by means of a number of joining. strings (not shown). In the latter position shown in Fig. 9, the join- ing strings have been broken and the first cap part 5 is pressed down into the second cap part 12.

In view of that stated above, it will be appreciat- ed that the embodiment shown in Figs 8-12 also has an inwardly directed annular flange 21 with recesses 22 for the two wings 20. This annular flange 21 has, however, in the third embodiment an extra function in connection with resealing of an opened container 2. This function is to put the first cap part 5 in a turning movement in connec- tion with such resealing. The reason for this is that the knowledge that a turning movement significantly facili- tates the placing of the first cap part 5 on the opening portion 3 of the container 2. The function is achieved by means of teeth 28 directed towards the container 2 and positioned on the inwardly directed annular flange 21 (see especially Fig. 10), which teeth 28, when screwing the second cap part 12 down on the container 2, engage opposite teeth 29 on the two wings 20 of the first cap part 5 (see especially Fig. 11).

It will be appreciated that the plastic cap describ- ed above may be varied in many ways within the scope of the claims. However, it is above all important to note that the liner 6 of the first cap part 5 must always ini- tially be non-rotatably connected to the opening end sur- face 9 of the container 2 and that the first cap part 5 itself must be bendable to achieve the desired"peeling- off effect".