METAL BOX LID

Description

[0001] The present invention relates to a metallic can lid with a resealable opening, in particular for beverage cans and for containers for storing food and other liquid, pasty, powdery and / or solid products.

[0002] EP 1 607 341 A1 discloses a can end with a resealable opening, in which an opening is provided in the metal can end and the edge of this opening is flanged to provide an anchoring option for a prefabricated plastic closure part. The plastic closure part comprises a base part which is to be connected to the flanged edge of the can opening and in which an opening closed by a flat plug is formed. The flat plug is connected to the opening edge via a plastic tear seam so that the flat plug, which is connected to a tear-open tab, can be detached from the plastic base part by pulling on the tear-open tab and can be pivoted into an opening point. The opening can be temporarily closed again by pressing in the flat plug, which is preferably conically shaped on its underside.

[0003] Resealable can lids are also described, for example, in US2004 / 159 665 A1, DE 10 2010 013 531 A1, DE 10 2015 112 428 A1 and EP 2 354 022 B1.

[0004] A can lid according to the preamble of claim 1 is known from US 2018 / 016058 A1.

[0005] The object of the invention is to provide a resealable can lid which is particularly inexpensive to manufacture and yet is easy to operate and has good sealing properties.

[0006] This object is achieved by a metallic can lid having the features of claim 1.

[0007] A micro-gap ensures particularly easy opening of the can lid, but a weakened line is also generally suitable. Effective closure and reclosure can be achieved via the sealing and locking ribs and the associated receiving grooves. It is particularly advantageous that the sealing frame is firmly bonded to the fixed lid surface and the closing unit is firmly bonded to the pivoting metal lid section.

[0008] According to the invention, the sealing and locking ribs, together with the receiving grooves, form at least two, preferably three, sealing edges. The sealing edges are designed such that, when the can lid is opened, the radially innermost sealing edge still seals even if the radially outer sealing edge or both radially outer sealing edges have just been released. In this way, a so-called venting of a can closed with the can lid can be achieved, i.e., a slow pressure reduction before the can lid is fully opened.

[0009] According to a preferred embodiment of the invention, the radially innermost sealing edge is spaced further from the lid surface than the other sealing edge or edges. As a result, the innermost sealing edge separates from the other sealing edge or edges, thus achieving the aforementioned venting.

[0010] According to a particularly preferred embodiment of the invention, at least the radially innermost sealing edge extends in a plane that is inclined relative to the plane of the cover region located within the micro-gap or the weakening line, with the two planes being spaced apart the greatest on the side facing away from the pivot bearing. This embodiment makes it possible for the innermost sealing edge to seal over its entire circumference until the outer sealing edge or the two outer sealing edges are released.

[0011] According to a further embodiment of the invention, the sealing and locking ribs on the one hand and the receiving grooves on the other hand are designed such that they increasingly interlock with each other as the can lid bulges. This ensures that the can lid remains closed even as the internal pressure in the can increases.

[0012] According to a preferred embodiment of this inventive concept, a locking rib provided on the sealing frame has an outward-facing hook that interacts with a correspondingly inward-facing locking projection of a receptacle of the closing unit. This design achieves increasing interlocking as the can lid bulges.

[0013] According to another embodiment of the invention, the tear-open member has an opening into which an extension of the closing unit engages. The extension is connected to the tear-open member so firmly, in particular by a material bond, that the extension is torn off the closing unit when the tear-open member is pivoted upwards. This embodiment creates a tamper-evident closure, i.e., a closure whose opening is irreversibly detectable.

[0014] According to a particularly preferred development of this inventive concept, the opening and the extension are provided in the area of ​​the pivot bearing of the tear-off part. This ensures that the extension is torn off as soon as the tear-off part is lifted, thus preventing any tampering with the can lid.

[0015] An embodiment of the invention is illustrated in the drawing and described below. They show, in schematic representation, Fig. 1 is a perspective view of a can lid according to the invention, Fig. 2 is a plan view of the top side of the can lid of Fig. 1 , Fig. 3 a section along line AA in Fig. 2 , Fig. 4 a section along line BB in Fig. 2 , Fig. 5Detail C of Fig. 3 in enlarged scale, Fig. 6Detail D of Fig. 3on an enlarged scale, Fig. 7 a plan view of the sealing frame of a can lid according to the invention, Fig. 8 a section along line AA in Fig. 7 , Fig. 9a section along line CC in Fig. 7 , and Fig. 10Detail B of Fig. 8 on an enlarged scale.

[0016] The can lid 1 shown in the figures is made of metal, in particular aluminum, and has a resealable opening. For this purpose, a hinged lid area 3 is provided in the lid in addition to a fixed lid surface 2. The hinged lid area 3 is separated from the fixed lid area 2 by a circumferential micro-gap 4 or a weakening line (see in particular Fig. 6 ).

[0017] A sealing frame 5 made of plastic material enclosing the opening area is connected to the fixed lid surface 2, in particular by a so-called hot-melt process using an adhesion promoter to ensure a secure connection to the aluminum of the lid. Furthermore, a closing unit 6, also made of plastic, is connected to the upwardly pivoting metallic lid area 3. This closing unit 6 is pivotally attached to the fixed lid surface 2 via a pivot bearing 7. The pivot bearing 7 and the closing unit 6 are in turn connected to the fixed lid surface 2 and the upwardly pivoting lid area 3, respectively, in particular by a hot-melt connection using an adhesion promoter.

[0018] On the side diametrically opposite the pivot bearing 7, the closing unit is connected to a pivotable tear-open element 8, which, when not pivoted up, is arranged parallel to the lid top 9. The tear-open element 8 is ring-shaped in a known manner and can be pivoted upwards relative to the lid surface about a pivot bearing 11 by engaging a finger in an engaging end 10.

[0019] The sealing frame 5 and the closing unit 6 interact to form a seal via sealing and locking ribs 12, 13, 14 on the sealing frame 5 and the corresponding receiving grooves 15, 16, 17 on the closing unit 6. This creates three sealing edges 18, 19, 20, which seal the opening area of ​​the can lid. This ensures the tightness of the can lid even when a micro-gap 4 is used between the pivotable lid area 3 and the fixed lid area 2.

[0020] How to do this, especially in Fig. 6 As can be seen, the radially innermost sealing edge 18 is further away from the lid surface than the other two sealing edges 19 and 20. The innermost sealing edge 18 therefore still seals even when the two outer sealing edges 19 and 20 have just been released when the can lid is opened. This allows for what is known as venting of the interior of the can, i.e., a slow reduction in pressure before it is fully opened.

[0021] As one can see especially in the Figs. 9 and 10As can be seen, the radially innermost sealing edge 18 runs in a plane I that is inclined relative to the lid plane II. The inclination is, for example, 1 to 2°, in particular 1.5°. This ensures that the innermost sealing edge 18 still seals over its entire circumference when the lid area 3 is pivoted upwards, even if the two outer sealing edges 19, 20 have just become detached. When venting the interior of the can, this can prevent liquid from escaping from the interior of the can to the outside.

[0022] As one can see especially in the Figs. 5 and 6As can be seen, the radially outermost sealing and locking rib 12 provided on the sealing frame 5 has an outward-facing hook 21 which interacts with a correspondingly inward-facing locking projection 22 of the associated receptacle 15 of the closing unit 6. This ensures that the sealing and locking rib 12 increasingly hooks into the receptacle 15 or its locking projection when the can lid bulges, for example due to increasing internal pressure in the can.

[0023] As one can see especially in the Fig. 2 and 6As can be seen, the tear-open member 8 has an opening 23 into which an extension 24 of the closing unit 6 engages. The extension 24 is connected to the tear-open member 8 so firmly, in particular by a material fit, that the extension 24 is torn off from the closing unit 6 when the tear-open member 8 is pivoted upwards. Such a firm connection can be achieved, for example, by melting the extension 24 after injection molding of this plastic part in such a way that it firmly connects to the part of the tear-open member 8 forming the opening 23. This can be achieved, for example, using a type of soldering iron.

[0024] How to Fig. 6 As can be seen, the opening 23 and the extension 24 are provided in the area of ​​the pivot bearing 11 of the tear-open element 8. This ensures that even a slight lifting of the tear-open element 8 is sufficient to tear off the extension 24.

[0025] In the illustrated embodiment, the inside of the can lid is laminated with a plastic film 25, which covers the entire inside of the lid. Alternatively, the plastic film can also be annular and extend only a few tenths of a millimeter, in particular 3 to 4 tenths of a millimeter, on both sides beyond the micro-gap 4 or the weakening line. Another possibility is to use a disk-shaped sealing film that extends radially outwards beyond the micro-gap 4 or the weakening line by a few tenths of a millimeter, for example 3 to 4 tenths of a millimeter. In this case, the sealing film can be designed as a largely flat disk. Both the annular and the disk-shaped sealing films are preferably designed as punched parts.

[0026] While the sealing frame 5 and the closing unit 6 are always attached to the outside of the can lid 1 and connected to the can lid via an adhesive, the inside of the lid can, in contrast to the exemplary embodiment, also be at least largely free of laminations and the like. However, the inside of the lid can be coated with a lacquer layer, particularly one suitable for food contact, to prevent contact between the product inside the can and the metallic lid material.

[0027] As one can see especially in the Figs. 5 and 6 can be seen, the closing unit 6, which is integrally connected to the fixed lid area 2, overlaps the micro-gap 4. In this way, the tightness of the can lid can be guaranteed even without a sealing film on the inside of the lid. List of reference symbols

[0028] 1Can lid 2Fixed lid area 3Elevating lid area 4Micro gap 5Sealing frame 6Closing unit 7Pivot bearing 8Tear-opening device 9Lid top 10Interlocking end 11Pivot bearing of 8 12Sealing and locking rib 13Sealing and locking rib 14Sealing and locking rib 15Receiving groove 16Receiving groove 17Receiving groove 18Sealing edge 19Sealing edge 20Sealing edge 21Hook 22Protrusion 23Perforation 24Extension 25Sealing film Level I Level II

Claims

1. A metallic can end (1) having a reclosable opening, in particular for beverage cans and for containers for storing foodstuffs and other liquid, pasty, powdery or solid products, having a microgap (4) or weakening line provided in the metallic end surface and peripheral about the opening, having a sealing frame (5) composed of plastic material connected to the fixed end surface (2) and surrounding the opening region, having a closure unit (6) which is composed of plastic material, which is connected to the upwardly pivotable metallic end region (3) disposed within the microgap (4) or the weakening line, which is pivotably attached to the fixed end surface (2) via a pivot bearing (7) and which is preferably provided with a tear-open member (8) which is upwardly pivotably connected to the closure unit (6) diametrically opposite the pivot bearing (7), wherein the sealing frame (5) and the closure unit (6) cooperate in a sealing manner via sealing and latching ribs (12, 13, 14) and associated reception grooves (15, 16, 17) and the metallic end region (3) disposed within the peripheral microgap (4) or the weakening line is received and held in the opening region of the end (1), wherein the sealing and latching ribs (12, 13, 14) form at least two sealing edges (18, 19, 20), preferably three sealing edges (18, 19, 20), with the reception grooves (15, 16, 17), characterized in that the sealing edges are configured such that on the opening of the can end (1), the radially innermost sealing edge (18) still seals when the radially outer sealing edge or the radially outer sealing edges (19, 20) have just been released.

2. A can end according to claim 1, characterized in that the radially innermost sealing edge (18) has a larger distance from the end surface than the other sealing edge or than both other sealing edges (19, 20).

3. A can end according to claim 1 or 2, characterized in that the radially innermost sealing edge (18) extends in a plane (I) which is inclined with respect to the plane of the metallic end region (3) disposed within the microgap (4) or the weakening line, with the two planes (I, II) having the greatest distance from one another at the side remote from the pivot bearing (7).

4. A can end according to any one of the preceding claims, characterized in that the sealing and latching ribs (12, 13, 14), on the one hand, and the reception grooves (15, 16, 17), on the other hand, are configured such that they increasingly interlock with one another with an upwardly arching can end (1).

5. A can end according to claim 4, characterized in that a latching rib (12) provided at the sealing frame (5) has an outwardly facing hook (21) which cooperates with a correspondingly inwardly facing latching projection (22) of an associated reception groove of the closure unit (6).

6. A can end according to any one of the preceding claims, characterized in that the tear-open member (8) has an aperture (23) into which a prolongation (24) of the closure unit (6) engages, with the prolongation (24) being so firmly connected, in particular bonded, to the tear-open member (8) that the prolongation (24) is torn off from the closure unit (6) on the upward pivoting of the tear-off member (8).

7. A can end according to claim 6, characterized in that the aperture (23) and the prolongation (24) are provided in the region of the pivot bearing of the tear-open member (8).