Liquid containers, and more particularly drink containers, are used on a large scale. <BR> <BR> <P>Drink containers of the type also designated as"drinks can", "can package"or"tin"are applied in particular for packaging and consumption of (optionally carbonated) drinks.

Soft drinks and beer are for instance packaged in large quantities in such substantially cylindrical drink containers, which are particularly known in the standard sizes of 330 ml and 500 ml. The drinks cans are however also applied in other standardized dimensions (there are for instance cans with a volume, among others, of 200 ml, 225 ml, 250 ml, 300 ml, 330 ml, 350 ml, 500 ml, "slim cans", "tall cans"and so on). The existing drink containers (at least the cylinder casing-shaped part including an integrally formed base) are generally manufactured using a stamp, whereafter a separate metal top part is then attached thereto by means of a folded seam connection. In the top part there is usually placed a tab which is surrounded by weakened portions and which can be torn loose using a ring fixed to the tab. For these cans use is made of aluminium or sheet steel as starting material, to which a coating can be applied as desired. The existing drink containers have the significant drawback that they are difficult to open and are not reclosable. There are also objections to the use of such drink containers since they are not very environmentally-friendly.

The present invention has for its object to provide an improved closure for a liquid container, an improved liquid container and a method for opening such a liquid container whereby an improved functionality can be provided with less of an environmental impact compared to the prior art liquid containers.

The invention provides for this purpose a closing device for a liquid container, more particularly a drink container, comprising: a wall part provided with a recess and a

shield member which is slidable between a first, closed position sealing the recess in the wall part and a second, opened position leaving the recess at least partly open, wherein the shield member is provided with a locking member securing the shield member in the first, closed position, and which locking member can be operated by displacing the shield member in a direction which encloses an angle with the wall part. The advantage of such a closing device is that the operations of unlocking and opening a (drinking) opening are separated such that both operations can be optimized independently of each other. It hereby becomes possible to leave clear an opening with lesser forces than according to the prior art and with simplified movements. In a preferred variant the passage opening for liquid can also be reclosed by sliding back the shield member, wherein it is also possible for the locking member to secure the shield member once again in the closed position. These are examples of the possible optimization of the separate functions of locking and closing.

The shield member preferably engages on the recess in the wall part. A separate provision on or in the wall part hereby becomes unnecessary ; use is made in simple manner of a provision which is in any case already present.

It is possible to envisage diverse variants in respect of the embodiment of the locking member. A simple variant relates to a pin pivotally connected to the shield member.

Such a pivotable pin can optionally be fully integrated with the shield member. Another option is to provide the shield member on one side of the wall part with a control element which is situated at least substantially on the side of the wall part remote from the shield member. The control element and the shield member can be mutually connected by means of a single or multiple connection which protrudes through the opening. In the case a control element is present which is separated from the shield member, it is logical to integrate the locking, or at least the control thereof, with the control element. It is also possible to integrate the guiding of the shield member relative to the wall part with the control element.

In yet another preferred variant, the closing device is provided with a gas passage which is closed in the first, closed position of the shield member and which is opened after displacing the shield member respectively the control member from the first, closed position relative to the wall part in a direction which encloses an angle with the wall part. A separately controllable gas passage has the advantage that, prior to displacement

of the shield member, a reduction in the pressure difference can first be realized between the internal and external pressure of a (drinks) container. After reduction in the pressure difference the shield member can be displaced with relatively little resistance.

Such a closing device is particularly useful for instance for sealing a carbonated drink container.

In yet another preferred embodiment, the shield member and/or the control element engage on the wall part via biasing means. The biasing means can herein exert a force directed toward the wall part on the shield member. The advantage hereof is that this can provide an improved sealing. Another measure for realizing an improved sealing is to place a seal between the shield member and the wall part. Such a seal can consist of a gasket of a flexible material. An example of such a material is EVOH. The possibly present separate gas passage can likewise be provided with a seal (valve) of the same material, and can herein be formed integrally with the gasket of the shield member.

If, in addition to being displaceable parallel to the wall part, the shield member is also displaceable to a limited extent in a direction perpendicular to the wall part, the frictional resistance between the wall part and the shield member (plus seals which may be present therebetween) can thus be decreased.

For a controlled displacement of the shield member relative to the wall part, it is desirable that the shield member connects to the wall part via a guide running at least substantially parallel to the wall part.

It is particularly advantageous to manufacture the wall part at least partly from plastic.

This is also the case for the shield member and an optionally present control element; these can also be advantageously manufactured from plastic. The more complex forms required for advantageous embodiment variants (such as for instance guide elements, fittings for seals, separate gas passage facilities and so on) can be manufactured easily and inexpensively from plastic, certainly in the case of production of components in larger volumes. Plastic is here also understood to mean a plastic-substitute material, such as for instance a modified cellulose. Another way of characterizing this material is as a"non-metal" ; the material from which the drink containers of the"drinks can"type have heretofore been manufactured for many years. It is already clear from the term

"drinks can"that the prior art teaching consists of manufacturing such a drink container from metal (tin). Specific examples of plastics to be applied are: PET, PE, PEN, PPE and HDPE. It is desirable here that the plastic-containing material is substantially form- retaining, i. e. the plastic material can fulfill a supporting function.

The invention also provides a cover of a liquid container provided with a closing device as described above, which is preferably manufactured from plastic. The invention moreover provides a liquid container provided with such a cover, wherein the cylinder casing-shaped part of the liquid container is manufactured from a plastic-containing material. It is possible here for the dimensions of the liquid container to fall within the standardized dimensions for drinks cans. Some important advantages of the application of plastic in the drink container according to the invention are that plastic can be relatively inexpensive, plastic (in particular when it is form-retaining) can be readily reused without having to be recycled immediately, it can be recycled in simple manner and that, depending on the application of the drink container, there are options in respect of the plastic which can best be applied for this specific application.

Furthermore, a plastic drink container can have a relatively low weight, a plastic drink container is not susceptible to oxidation and the plastic can function as a (thermal and electrical) insulator. It is also easier to inspect the contents of plastic drink containers by means of for instance X-radiation or other radiation. All these advantages can be realized in combination with retaining (practically) the entire infrastructure appropriate for prior art drinks cans, such as for instance filling lines, packing equipment, transport means, supply containers, cooling means, vending machines and so on.

Plastic also makes it possible however to manufacture a liquid container with a form which differs from the standard dimensions for drinks cans. The cover usually connects onto a cylinder casing with integrally formed base part. In respect of the shape of the liquid container it is possible, partly owing to the application of plastic as the basic material, to give drink containers in particular all kinds of differing forms.

In another advantageous embodiment variant, the top part is formed such that a protruding edge (which is usually circular) arranged around the drinking opening is now provided with a portion that protrudes less than the other part of the edge. This lowered portion of the edge makes it simpler to pour or drink from a drink container; the raised

edge can be interrupted locally so as not to result in an obstruction (or in less of one).

When plastic is applied as construction material, the cover and the cylinder casing- shaped part can be provided with form-fittingly co-acting contact sides (examples are a "snap closure", a screw top and a bayonet fitting). Such a closure can then replace the folded seam usual in metal. For a good sealing the cover can connect to the cylinder casing-shaped part via a seal. It is also advantageous to manufacture the cover from a material similar to the material from which the cylinder casing and a base part are manufactured. A single material (mono-material) for all components makes a product easier and cheaper to recycle.

Alternatively, the liquid container can also be manufactured from a plastic-containing material of laminar construction which is provided with one or more material layers consisting of a material other than plastic. Such a material layer other than plastic can be applied in particular as an extra barrier layer to prevent for instance oxygen exchange, odour exchange between the contents of the drink container and the environment and/or the plastic. Examples of such a layer co-acting with the plastic are metal coatings, and more particularly for instance a chrome coating, EVA (ethylene vinyl acetate) and EVOH (ethylene vinyl alcohol). Such a layer can also be applied between for instance two PET layers. When two PET layers are separated by a barrier layer, the demands which can be made of the plastic situated on the outside of the drink container can differ from those made of the plastic which is situated on the inside and which comes into contact with the contents of the drink container; RPET (recycled PET) can for instance be used as plastic on the outside.

The invention further also provides a method for opening a liquid container as described above, with the successive process steps of A) displacing the shield member in a first direction of movement, which first direction of movement encloses an angle with the wall part, thereby releasing a locking against mutual displacement of the shield member and the liquid container in a second direction of movement, which second direction of movement is substantially parallel to the wall part, and B) mutually displacing the shield member and the wall part in the second direction of movement. When the shield member is displaced in the second direction of movement, the distance between the wall part and the shield member can also increase. During process step A) a passage can simultaneously also be created between the interior of the liquid container and the

environment. For the advantages of these methods reference is made to the advantages of the closing device and the drink container according to the present invention already described above.

The invention will be further elucidated on the basis of the non-limitative exemplary embodiments shown in the following figures. Herein: figure 1 shows a perspective schematic view of a closing device according to the present invention, figure 2A shows a schematic cross-section through the closing device of figure 1 in a closed, locked position, figure 2B shows a schematic cross-section through the closing device of figure 2A in a closed, unlocked position, figure 2C shows a schematic cross-section through the closing device of figures 2A and 2B in an opened position, figure 3 shows a schematic cross-section through an alternative embodiment variant of the closing device according to the present invention in a closed, locked position, figure 4A shows a schematic cross-section through a second alternative embodiment variant of the closing device according to the present invention in a closed, locked position, figure 4B shows a schematic cross-section through the closing device of figure 4A in a closed, unlocked position, figure 5A shows a schematic cross-section through a third alternative embodiment variant of the closing device according to the present invention in a closed, locked position, figure 5B shows a schematic cross-section through the closing device of figure 5A in an opened position, figure 6 shows a schematic cross-section through a third alternative embodiment variant of the closing device according to the present invention provided with a control element, figure 7A is a perspective view of a drink container according to the invention, figure 7B is a perspective view of the drink container shown in figure 7A in exploded state, figure 8A is a perspective view of a cut-away part of the drink container of figures 7A and 7B in a closed position,

figure 8B is a perspective view of the cut-away part of the drink container shown in figure 8A in an opened position, figure 9 is a perspective view of a detailed view of a cross-section through the drink container shown in figures 7A-8B, figure 10 is a perspective detail view of a folded-open operating member as this forms part of the drink container shown in figures 7A-9, and figure 11 is a perspective view of the drink container shown in figures 7A-10 in a situation exploded into two parts.

Figure 1 shows a closing device 1 with a wall part 2 in which is located a recess 3.

Recess 3 is closable by a shield member 4 which is slidable relative to wall part 2 and which is provided for this purpose with opposite guides 5 which engage on edge parts of recess 3. In the shown position shield member 4 leaves a part of recess 3 clear such that for instance drink (not shown) can flow through recess 3. in order to secure shield member 4 in a position sealing the recess 3, shield member 4 is provided with a lock 6, the operation of which will be further described with reference to figures 2A-2C.

Figure 2A shows closing device 1 in a closed position. Shield member 4 here completely covers the opening 3 in wall part 2. Because a pin 7, situated on the side directed toward wall part 2 and forming part of lock 6, engages on an edge of opening 3 formed by wall part 2, the shield member cannot be freely displaced relative to wall part 2 (pin 7 locks against sliding of the shield member in one direction). By now exerting a pressure on lock 6 in direction Pi as shown in figure 2B, pin 7 can be lifted such that it no longer engages on the edge of opening 3 formed by wall part 2. This has the result that, as shown in figure 2C, shield member 4 can be displaced as according to arrow P2 such that shield member 4 leaves the opening 3 partly clear.

Figure 3 shows an alternative embodiment of a closing device 10, with a shield member 11 which engages on an edge 14 of a recess 15 in wall part 12 by means of a pin 13 arranged on the side directed toward a wall part 12. By exerting a tensile force as according to arrow P3 on a grip 16 forming part of shield member 11, the engagement of pin 13 on edge 14 can be released, for instance through deformation of shield member 11 as a result of the tensile force exerted. Shield member 11 can then be displaced relative to wall part 12.

Figure 4A shows yet another closing device 20 with a shield element 21 of which a locking pin 22 forms part. Pin 22 engages on an edge 23 of a recess 24 in a wall part 25.

As shown in figure 4B, locking pin 22 can be displaced such that it no longer engages on edge 23; the locking is hereby released and shield element 21 can slide relative to wall part 25. Recess 24 can hereby be left partially clear.

Figure 5A shows a closing device 30 with a shield member 31, a locking pin 32 of which protrudes such that this locking pal 32 engages on an edge 33 of an opening 34 in a wall 35 of for instance a drink container (not shown). Through deformation of shield member 31, see figure 5B, locking pin 32 can be bent away from edge 33 such that shield member 31 can now slide over a limited distance relative to wall 35.

Closing device 40 shown in figure 6 is provided with a shield member 41 and a control element 42 connected to shield member 41. Shield member 41 and control element 42 are situated on opposite sides of a wall part 43, in which a recess 44 is left clear.

Between shield member 41 and wall part 43 is placed a gasket 45 for preventing leakage in the closed position of closing device 40.

Figure 7A shows a drink container 50 with a cylindrical lower part 51 which is manufactured from plastic and to which connects a plastic cover 52. Placed in cover 52 is a closing device 53 slidable relative to a cover surface 52. The cover is provided with a protruding edge 54 with a locally lowered portion 55. This lowered portion 55 of edge 54 makes it easier to pour liquid (drink) from the drink container, and more particularly makes it easier to drink from drink container 50.

In figure 7B drink container 50 is exploded into a number of components. Cover 52 is separated from a shield member 56 which, in the assembled state of drink container 50, lies against the underside of cover 52 via a seal 57 (gasket) manufactured from a flexible material. Also separated is a control element 58 which connects to shield member 56 in the assembled state. Shield member 56 and control element 58 are herein located on the opposite sides of a wall part 59 which forms part of cover 52. Arranged in wall part 59 is a first opening 60 for the passage of drink, as well as a second opening

61 for reduction in the pressure difference in drink container 50 before the first opening 60 is left clear.

Figure 8A shows a cross-section through the upper part of drink container 50. Shield member 56 is connected to control element 58 by means of a form-fitting coupling 62 such that wall part 59 is engaged on both sides. Control element 58 comprises a pivotable blocking member 63, the operation of which will be further elucidated in the following figure. Control element 58 is also provided with a protrusion 64, with which the second opening 61 can be left at least partially clear by pressing in control element 59. The clear second opening 61 provides for a reduction in the pressure difference between the inside of drink container 50 and the outside. Pressing in of control element 59 also results in the pivotable blocking member 63 being operated such that the way is cleared for sliding of the assembly of control element 58 and shield member 56. Sliding of the assembly is simplified by the reduction in the pressure difference. After sliding of the assembly the first opening 60 is left partially clear such that liquid can be removed from the drink container (see figure 8B). Figures 8A and 8B also show the form-fitting coupling 65 ("snap closure") between the plastic cover 52 and the cylindrical lower part 51 (this can however also have a form other than cylindrical).

Figure 9 shows an enlarged view of a part of control element 58 and shield member 56.

By displacing control element 58 downward the pivotable blocking member 63 is rotated such that it will become detached from a bearing 66 in wall part 59. During the downward displacement of control element 58 the protrusion 64 will also press a plug 67 out of the second opening 61 in the wall part. It is noted that plug 67 can be manufactured as a single component with gasket 57.

Figure 10 shows control element 58 in a folded-open position. The pivotable blocking member 63 is clearly visible. Protrusion 64, which will protrude through an opening 68 arranged for the purpose, can also be seen. Finally, figure 11 shows drink container 50 in a situation where cover 52 is detached from drinks can 51. After filling of drinks can 51 with for instance drink, cover 52 can be snapped fixedly thereon.