OA18840A - Resealable can lid. - Google Patents

Abstract

The invention relates to a can lid of a conventional design, in particular intended for beverage cans, whose special feature comprises the fact that a substantially ring-shaped molded plastic part is fastened to the lower side of the lid surface surrounding the opening region to form an opening that is sealingly reclosable, in that a plastic stopper part is fixedly connected to the lower side of the tongue tab that is upwardly pivotable during the opening procedure and sealingly engages into the molded part, and in that the peripheral contour of the tongue tab is preferably disposed in the region of the molded part at a predefinable spacing from the stopper part.

Description

CAN LID, RECLOSABLE

The invention relates to a can lid, in particular for beverage cans, having an opening région in the form of a tongue tab provided in the metallic lid material of a lid surface and in particular bounded by a material weakening, having a two-armed lever member that is intended for opening this opening région, that is in particular fixediy connected to the lid material in the opening région, in particular via a rivet connection or weld connection, and that serves for pivoting the tongue tab upwardly during the opening procedure.

Can lids of this kind are use to an extremely large degree ail over the world. They can be manufactured simply and inexpensively and allow a space-saving stacking of the cans as well as an opening of the cans by a simple upward pivoting of the long arm of the lever member.

However, these generally known can lids hâve disadvantages that, for example, comprise a reclosing of a lid not being possible once it has been opened, the lid part région initially closing the opening région is pressed into the can interior on the upward pivoting of the lever member and on the opening of the can taking place in this process and there cornes into contact with the liquid which is hygienically problematic, and tiny articles being unavoidably released from the lid material and being able to enter into the can interior during the opening procedure,

i.e. when the weakening groove present in the lid material between the opening région and the lid surface is torn open or separated.

A can lid having a reclosable opening is known from WO 2011/095319 A1 in which the opening région of the can is formed as a closure lid and is connected at its outer margin adjacent to the tear notch with a collar part of a first plastic material in a force-transmitting manner and a lid receiving part of a second plastic material that is connected outside the opening région and adjacent to the tear notch to the lid surface in a force-transmitting manner is associated with the collar part. The collar part in this respect engages over the lid receiving part and a sealing snap-in connection having a peripheral coupling rib and a recess shaped in a complementary manner are formed between the collar part and the lid receiving material. The pull tab is fastened radially outside the lid receiving part to a fixing région of the collar part and the two-armed lever is formed to pierce the tear notch by a partial peripheral région of the collar part associated with the fixing région.

A can lid having a reclosable opening îs known from EP 1 607 341 A1 in which an opening is introduced in the metallic can lid and the margin of this opening is beaded to create an anchorage possibility for a prefabricated plastic closure part. The plastic closure part encloses a base part which is to be connected to the bead rim of the can opening and in which an opening closed by a fiat stopper is formed. The fiat stopper is connected to the opening margin via a plastic tear seam so that the fiat stopper connected to a tear tab can be released from the base plastic part via the tear tab by exertion of a pull and can be pivoted into an open position. The opening can be temporarily closed again by pressing in the fiat stopper which is preferably conical at its lower side.

A can lid having a reclosable opening is known from WO 2008/098558 A1 in which an opening into which a prefabricated tearable plastic closure part is inserted is likewise introduced in the métal can lid, with the prefabricated plastic element having a double flange at the marginal side into which the margin of the stampedout can opening engages and is fixed therein. The prefabricated plastic element includes a closure part which is connected to the peripheral margin of the plastic

part via a tear seam. A tear tab connected to the closure part makes it possible to tear open the plastic tear seam between the peripheral région of the plastic part and the lid part and to release the can opening in this manner. For the purpose of reclosing, the closure part which preferably remains in connection with the peripheral région via a tab région is pressed back into the opening.

A reclosable can lid is known from GB 1 389 351 in which in particular the création of sharp edges should be avoided such as occur on opening usual sheet métal cans via a tab. For this purpose, a punching provided in the metallic can lid is snapped into a prefabricated plastic part which has a lid part which is connected to the base part snapped into the can opening via a thin plastic wall. The thin connection wall between the connection part and the base part can be destroyed via a tear tab and the can opening can be exposed. The closure part is designed in this respect such that it engages into the base part via a snap-in latch connection to reclose the opening.

A beverage can is known from DE 89 11 286 U having a press-in lid closure in which the tear tab is rotatably supported at the lid wall and a closure element is provided thereat which is taken along on the rotation of the tear tab from the tear position into a closure position above the opened pouring opening and engages over or overlappingly into the pouring opening.

A beverage can is known from DE 90 05 150 U having a lid which is composed of sheet métal, in which an attenuating line is formed and the lid part bounded by the weakening line can be separated by means of a pull tab, with a closure part for the removal opening pivotable substantially in parallel with the lid surface being captively fastened to the lid.

A lid of métal for beverage cans is known from DE 196 13 246 which has a prepunched pouring opening in the lid surface which is tightly closed by means of

a closure element and can be tightly closed again after the first opening. In this respect, the lid and the closure element can be connected to one another in a shape-matched manner by éléments which engage into one another in the manner of a bayonet and which are formed directly out of the lid material or the closure element.

It is the object of the present invention to adapt the can lid in accordance with the preamble of the claim in a manner such that a repeated, sealing reclosing of an open can is made possible and the procedure of opening the can is preferably also facilitated or the force effort required therefor is reduced. The construction design of the can lid should furthermore be made as simple and as inexpensive as possible and a problem-free automatic assembly should be made possible.

This object is substantially satisfied in that a substantially ring-shaped molded plastic part is fastened to the lower side of the lid surface surrounding the opening région to form an opening at the lower side of the lid surface that is sealingly reclosable, in that a plastic stopper part is fixedly connected to the lower side of the tongue tab that is upwardly pivotable during the opening procedure and sealingly engages into the molded part, and in that the peripheral contour of the tongue tab is preferably positioned in the région of the molded part at a predefinable spacing from the stopper part.

It is of particular importance in this solution that the éléments décisive for the reclosing capability of the can are disposed in the inner space of the can and that the outer appearance of this reclosable can thus practically does not differ from a conventional can, i.e. a non-reclosable can, and in particular no plastic éléments can be seen at the outer side of the can lid.

The can lid in accordance with the invention can thus be provided with a weakening groove in accordance with a basic embodiment analog to a

conventional can lid, said weakening groove being pierced on an upward pivoting of the lever, whereupon the tongue tab bearing the stopper part can be pulled upward so that the opening becomes free. On the pivoting back of the tongue tab, the stopper then moves in a sealing manner agaîn into the molded part sealingly receiving it where it is latchingly held until the next opening procedure. The opening and closing procedure can then be repeated as required.

In accordance with an advantageous embodiment of the invention , the stopper part is configured as a hollow stopper having a concave base wall and can be coupled to the molded part receiving it via a snap-in connection.

The concave design of the base wall produces the advantage in this respect that the concave base wall îs deformed in the direction of the can lid due to the inner pressure present or building up in a can and the contact pressure of the peripheral stopper wall toward the wall of the ring-shaped molded part is thereby increased and thus the sealing is also further improved.

A further advantageous feature of the invention can be seen in the fact that the molded part and the stopper part are sealingly connected to the lid material via a sealing layer that preferably extends over the entire lower lid side.

The sealing layer in the form of a sealing wax or of a hard lacquer finish provided at the lower lid side can be activated by the effect of heat, e.g. at approximately 120°C, and allows an absolutely reliable and secure connection between the métal parts and the plastic parts.

The ring-shaped molded part preferably has a nose that is associated with the région of the tongue tab end and whose end région is fixedly connected to the lid material via the sealing layer.

It is possible in this manner to provide a free région between the ring-shaped molded part and the end région of the molded part nose, with said free région allowing an upward pivoting of the longue tab bearing the closure stopper about a pivot bearing that has a sufficient spacing from the opening that becomes free to ensure an unimpeded drinking from the can.

It is of advantage from a technical production aspect if the molded part and the stopper part comprise an injection molded part connected via a flexible, separable tab since a problem-free automatic pivoting into one another of both parts and a completing further processing of the single-part structure obtained in this way can take place on the assembly in this manner.

An independent advantageous aspect of the invention is characterized in that the tongue tab connected to the stopper part at the lower side is separated from the lid surface by a microgap, in particular a stamped gap, extending over the periphery of the tongue tab and the tongue tab base connected to the lid surface forms a pivot bearing that becomes effective during the opening procedure, and in that the lower side of the metallic lid is coated in a firmly adhering manner with a sealing plastic material.

The presence of a microgap instead of a material weakening is of particular importance in this embodiment. The leak tightness of the can is ensured in this case by the molded plastic part that contacts the lower lid side in a sealingly adhering manner and that covers the microgap.

The microgap is preferably obtained by a punching procedure with a subséquent return of the tongue tab pressed out of the can lid material into its starting position before the punching. The opening of the can with a small force is a conséquence of the fact that no séparation of métal is necessary.

A further independent embodiment of the invention comprises the fact that the longue tab of the metallic can iid is separated from the lid surface surroundîng it by a cutting process, in particular a stamping process, while forming mutually engaging projections and recesses and that the tongue tab and the lid surface adjacent thereto are connected in a shape-matched and force-transmitting manner via the projections and recesses while forming a microgap.

After the opening procedure, the margin of the metallic lid material at the moided part side lies in a protected manner on the upper end wall of the ring-shaped moided part and the peripheral margin of the tongue tab formed in a complementary manner is very largely protected against contact by the stopper part borne by the tongue tab.

Different embodiments of the invention that are to be considered as independent aspects differ in that the microgap formed by the recesses and the projections extends in the manner of a dovetail, of a trapeze or of a wavy line in a mutually engaging manner.

In addition to the can lid described in detail, the invention also covers ail cans that are provided with a can lid in accordance with the invention.

Further advantageous features of the invention resuit from dépendent daims and from the following description of an embodiment of the invention with reference to the drawing.

There are shown in the drawing:

Fig. 1 a plan view of an embodiment of a can lid in accordance with the invention,

Fig. 2 a sectional view of the can lid of Fig. 1,

Fig. 3 an enlarged detailed view of the closure région of Fig. 2;

Fig. 4 a perspective représentation of the molded part injection molded in one part for forming the stopper part and the ring-shaped molded part receiver;

Fig. 5 a perspective représentation of the can lid of Fig. 1 in a partly exposed or open state; and

Fig. 6 a perspective représentation of the can lid of Fig. 1 from below in a partly exposed condition.

Fig. 1 shows an embodiment of the can lid in accordance with the invention in a schematic plan view. This can lid is provided at its peripheral région with a bead rim 2 in a conventional manner, wherein the région disposed within the bead rim 2 is formed by a lid surface 3 that has an opening région formed as a tongue tab 4 offset with respect to the center. This metallic can lid comprising aluminum material is provided in a manner surrounding the opening région 4 with at least one stiffening région 14 formed by material deformation.

A two-armed lever 5, 6 is connected, in particular riveted or welded, to the tongue tab 4 of the can lid 1 defining the opening région such that a fixed connection point 7 results. This connection point 7 is disposed in the marginal région of the tongue tab 4 or of the opening région, i.e. opposite the tongue base that is connected to the lid surface 3 and that forms a pivot bearing région 9 during the opening procedure. The two-armed lever comprises a shorter région and a longer région, wherein the longer région is preferably formed by a ring tab 5 that can in particular be easily gripped due to a concave design of the opening région and the shorter

région is formed by a support limb 6 that is supported on a stiffening région of the can lid easîly absorbîng the corresponding counter-forces on the upward pivoting of the longer lever, The opening région 4 is accordingly pried open on the upward pivoting of the longer lever, which will be presented in detail below,

The two-armed lever 5, 6 lies substantially in parallel with the lid surface 3 in the starting state such that the overall Visual impression of the lid in the plan view substantially corresponds to a conventional can lid and the corresponding stacking properties of cans equipped with such a can are accordingly also ensured.

The tongue tab forming the opening région 4 is coupled in a shape-matched and force-transmitting manner to the lid surface 3 via projections 12 and recesses 13 and preferably via suitable undercuts of these parts, and indeed with the exception of the région of the tongue base where the opening région 4 and the lid surface 3 are connected in a metallic manner such that an upward pivoting of the tongue tab is made possible by means of the lever practically via a kind of folding joint 9 on the opening of the can and the tongue tab 4 and the lever 5, 6 can then move into a position of rest outside the inner can space while releasing the opening, in which position of rest a comfortable drinking from the can is ensured.

In this end position, that is reached after the upward pivoting of the tongue tab 4, a retaining effect with respect to the tongue tab is preferably achieved by a suitable bead formation in the material of the can surface and holds the tongue tab in the fully openly pivoted position out of which it can, however, be moved again by exerting a light pressure in the closing direction.

Fig. 2, that shows a section through the can lid of Fig. 1, allows the éléments and construction details to be recognized that are décisive for the reclosing capability of the can lid in accordance with the invention.

The total lower side of the metallic can lid is preferably covered by a sealing layer, in particular a heat sealing layer, that is naturally very thin and that is not shown in the drawing.

The required leak tightness of the can lid is ensured despîte the lack of a continuous métal connection between the lid surface 3 and the tongue tab 4 in the région of the microgap 8 by a molded plastic part 15 that is sealingly connected to the lid material and that covers the microgap 8.

The substantially ring-shaped molded plastic part 15 that surrounds the opening région is fixedly connected to the lower side of the can surface 3 via the mentioned sealing layer. A plastic stopper part 16 is provided that is associated with this ringshaped molded plastic part, that is received therein in a shape-matched manner, that is formed as a fiat hollow stopper and whose end surface is in turn firmly connected to the metallic tongue tab 4 via the sealing layer. The stopper part 16 that forms a sealing closure element with respect to the ring-shaped molded part 15 is thus taken along on an upward pivoting of the tongue tab 4, i.e. the can is opened, and, on a backward pivoting of the tongue tab 4 into Its original starting position, the stopper part 16 in turn sealingly engages into the ring-shaped molded part 15 and thus closes the can.

The enlarged detailed représentation of the functional région of the can lid in Fig. 3 shows further substantial details of the solution in accordance with the invention realized in this embodiment.

The molded part 15 sealingly and firmly connected to the lower side of the lid surface has a flange région or support région 23 that is associated with the short lever arm 6 and that can, together with the can surface, absorb the forces arising on the prying open of the tongue tab without problem.

Approximately diametrically opposed to this support région 23, the molded part 15 is provided with a nose région 20 that merges into an end région 21 in turn firmly and sealingly connected to the lid surface. A free space 24 is provided between the ring-shaped part of the molded part 15 and the end région 21 and allows an unimpeded upward pivoting of the tongue tab via a pivot bearing, as is illustrated in Fig. 5.

The ring-shaped inner wall of the molded part 15 and the outer wall of the stopper part 16 are designed with respect to their shapes such that an unimpeded inward and outward pivoting of the stopper part with respect to the pivot bearing is possible, with the stopper part engaging in a shape-matched and sealing manner into the ring-shaped molded part and with a snap-in connection between the stopper part and the molded part becoming effective in the closed state. For this purpose, the ring-shaped molded part 15 is provided in the région of its lower end with a preferably peripheral recess 18 into which a corresponding projection 19 at the stopper part can engage via adapted sloping surfaces, whereby the releasable latching of both parts is ensured.

The base wall 17 of the stopper part 16 is preferably concavely curved, whereby it is achieved that a spreading effect occurs in the stopper part due to the excess pressure that is present in the respective can that increases the pressing toward the inner molded part wall and thus increases the sealing between both parts.

It has already been emphasized that a microgap 8 is preferably provided between the tongue tab 4 and the lid surface 3. This microgap 8 can be formed in different manners, for example in the manner of a dovetail joint or in the form of a wave line preferably having undercut régions, with the position of this microgap 8 with respect to the separating line at the lid side between the molded part 15 and the stopper part 16 having to be taken into account independently of the respectively selected embodiment of the microgap 8.

Fig. 3 in particular allows it to be recognized that this microgap 8 is preferably disposed radially outside the mentioned separating line. The microgap 8 is accordingly located in the région of the connection surface of the molded part 15 to the lid material and extends at a small spacing from the separating gap between the molded part 15 and the stopper part 16.

The plastic sealing layer that cannot be seen in the représentation in accordance with Fig. 3 and that is provided between the plastic éléments 15, 16 and the lower side of the lid surface 3 can easily be peeled off on the opening of the can lid and on the pulling up of the tongue tab 4 and the stopper part 16 so that an opening of the can is made possible that takes place with a particularly small exertion of force,

To achieve this design of the can lid that works with a microgap and that precludes any formation of métal splinters on the opening of the can lid, the opening région or the tongue tab is separated from the surrounding lid surface by a cutting procedure or preferably by a punching procedure on the production of the can lid, wherein the splinters or microparticles that are thereby produced can be eliminated completely and without problem as part of the production process. The tongue tab, that is still connected to its base by the lid surface 3, is pressed back into the lid surface plane directly after its punching out such that the original appearance practically results for the lid surface, but now with a microgap 8 produced by the punching procedure. After this machining, the lid unit can be further processed like a normal, single-part structure.

Instead of the toothed arrangement shown in the drawing, different, optionally simplet, gap line extents can be implemented in accordance with the invention in the punching procedure, wherein, however, the opening région or the tongue tab 4

in every case remains connected to the lid surface 3 via a pivot bearing région 9 and the microgap is covered by the molded plastic part.

The perspective représentation in accordance with Fig. 4 shows an embodiment of the molded plastic part 15 and of the plastic stopper part 16 as a single-part injection molded part. The ring-shaped molded part 15 and the stopper part 16 are in this respect connected via a tab 22, whereby it is possible without problem as part of an automatic production to press the stopper part through a pivot procedure into the molded part and to latch it therein so that then the sealing of this then practically single-part component with the lower lid surface can take place in the already described manner. The tab 22 can be removed when it is no longer required.

The perspective représentation in accordance with Fig. 5 shows the previously already described embodiment of a can lid in a partly open State.

To reach this state, the ring-shaped longer lever 5 has to be gripped and pivoted upwardly, whereby the shorter part 6 of the two-armed lever is pressed toward the lid surface 3 that is stable in its support région and as a conséquence thereof a prying open effect is produced with respect to the tongue tab 5 bearing the stopper part 16.

The tongue tab 4 and the stopper part 16 firmly connected thereto can then be upwardly pivoted and held in the end position in a simple manner only requiring a little force via the pivot bearing région 9.

It can also be seen from Fig. 5 that the toothed éléments associated with the microgap are disposed in protected régions, i.e. in practically contact-free régions, both at the lid side and at the stopper side.

The stopper part 16 can be pressed out of the pivoted-open State in which the can opening is completely released back into the closed position in which the can îs again sealingly closed without problem, A repeat opening procedure practically takes place in an analog way to the original opening procedure.

The perspective view in accordance with Figure 6 show a bottom view of the partly open can lid in accordance with Fig. 5. In this respect, both the ring-shaped molded plastic part 15 with its noses 20, 21 and the stopper part 16 sealingly engaging into this molded part 15 and with the arched base wall 17 can be recognized. The lower side or inner side of the can lid is covered by a sealing layer 10 in the manner aiready mentioned a number of times.

Not only the simplicity of the solution in accordance with the invention becomes clear in this illustration, but also the fiat construction producing a small space requirement. The ratio of stopper diameter to stopper depth is, for example, in the range of approximately 5 to 6 to 1.

As described, not only substantial disadvantages of the previously known and widespread can lids are avoided by the invention, but at the same time a reclosing capability of a can is achieved that substantially increases the practical value, with it being of spécial importance that ail these advantages are obtained without any substantial increase in technical production effort.

The closure opening and reclosing system described fora can lid here can also be used in an analog manner for other containers and packages that are to be equipped with a tear closure.

Reference numéral list can lid bead rim lid surface tongue tab and opening région lever arm, long lever arm, short fastening point microgap pivot bearing région sealing layer projection recess stiffening région ring-shaped molded plastic part plastic stopper part base wall cut-out projection molded part nose molded part end région tab support free space

Claims (15)

Claims

1. A can lid having an opening région (4) in the form of a tongue tab that is provided in a metallic lid material of a lid surface (3); and having a two-armed lever member (5, 6) intended for opening this opening région (4) that is connected to the lid material in the opening région (4), and that serves for an upward pivoting of the tongue tab (4) during the opening procedure, characterized in that a ring-shaped molded plastic part (15) is fastened to a lower side of the lid surface (3) while surroundtng the opening région (4) to form an opening that can be sealingly closed again; and in that a plastic stopper part (16) is connected to a lower side ofthe tongue tab (4) that can be pivotably opened during the opening procedure and sealingly engages into the molded plastic part (15).

2. A can lid in accordance with claim 1, characterized in that the plastic stopper part (16) is configured as a hollow stopper having a concave base wall and can be coupled to the molded plastic part (15) receiving it via a snap-in connection (18,19).

3. A can lid in accordance with claim 1 or claim 2, characterized in that the molded plastic part (15) and the plastic stopper part (16) are sealingly connected to the metallic lid material via a sealing layer (10).

4. A can lid in accordance with claim 3, characterized in that the ring-shaped molded plastic part (15) has a nose (20) that is associated with the région of a tongue tab end (7) and whose end région (21) is fixedly connected to the metallic lid material via the sealing layer (10).

5 lever member (5, 6) is connected off-center at a marginal side to the tongue tab (4) bearing the plastic stopper part (16).

20. A can lid in accordance with claim 12 or claim 19, characterized in that the gripping tab is a ring tab.

21. A can lid in accordance with one or more of the preceding daims, characterized in that a peripheral contour of the tongue tab (4) is disposed in the région of the molded plastic part (15) at a predefinable spacing from the plastic stopper part (16).

5. A can lid in accordance with one or more ofthe preceding claims, characterized in that the molded plastic part (15) and the plastic stopper part (16) comprise an injection molded part connected via a flexible, separable tab (22).

6. A can lid in accordance with one or more of the preceding claims, characterized in that the tongue tab (4) connected to the plastic stopper part (16) at the lower side is separated from the lid surface (3) by a microgap (8) extending over the perîphery of the tongue tab; and in that a tongue tab base connected to the lid surface (3) forms a pivot bearing (9) that becomes effective during the opening procedure; and in that the lower side of the metallic lid (1) is adhesively coated with a sealing plastic material.

7. A can lid in accordance with one or more of the claims 1 to 5, characterized in that the tongue tab (4) of the metallic can lid (1) is separated from the lid surface (3) surrounding it while forming mutually engaging projections (12) and recesses (13) by a cutting procedure; and in that the tongue tab (4) and the lid surface (3) adjacent thereto are connected via the projections (12) and recesses (13) in a shape-matched and force-transmitting manner while forming a microgap (8), with the leak tightness of the completed, unopened can lid being ensured by the sealed on molded plastic part covering the microgap (8).

8. A can lid in accordance with claim 7, characterized in that the projections (12) and the recesses (13) are coupled via undercuts.

9. A can lid in accordance with claim 8, characterized in that the projections (12) and the recesses (13) engage into one another in the manner of a dovetail, a trapeze or a wavy line.

10. A can lid in accordance with one or more of the preceding daims, characterized in that latching éléments are provided for a releasable holding of the open-pivoted tongue tab (4) bearing the plastic stopper part (16) in its open-pivoted end position.

11. A can lid in accordance with one or more of the preceding daims, characterized in that stabilizing beads are formed in a pivot bearing région (9) of the lid surface (3) to hold back the tongue tab (4) bearing the plastic stopper part (16).

12. A can lid in accordance with one or more of the preceding daims, characterized in that the two-armed lever member (5, 6) is metallic and is connected off-center to the tongue tab (4) bearing the plastic stopper part (16), and a longer arm (5) of the twoarmed lever member (5, 6) is formed by a gripping tab.

13. A can lid in accordance with one or more of the preceding daims, characterized in that it is for beverage cans.

14. A can lid rn accordance with one or more of the preceding daims, characterized in that the opening région (4) in the form of a tongue tab is bounded by a material weakening.

15. A can lid in accordance with one or more of the preceding daims, characterized in that the two-armed lever member (5, 6) intended for opening the opening région (4) is connected to the metallic lid material in the opening région (4) via a rivet connection (7) or weld connection.

16. A can lid in accordance with daim 3, characterized in that the sealing layer (10) extends over the total lower lid side.

17. A can lid in accordance with claim 6, characterized in that the microgap (8) is a stamped gap.

18. A can lid in accordance with claim 1, characterized in that the cutting procedure is a punching procedure.

19. A can lid in accordance with claim 12, characterized in that the metallic two-armed

15 22. A can having a can lid in accordance with one or more of the preceding daims with the can connected to the can lid via a beaded rim (2).