The invention relates to the technical sector concerning lids for containers, for example cans and the like.
The lid covering this type of containers is constituted by a disc, a perimeter edge of which is appropriately bent and fixed to the external flank of the container.
The most simple and economical containers are made as described above and their opening is performed with the aid of suitable tools, for example can-openers, which cut the lid and leave the cut portion with a particular saw-tooth shaped profile that is very sharp.
In a second type of lid, a pre-fracture line is provided on the upper surface of the disc, realised in proximity of the edge of the lid, and a tab is provided fixed on the upper surface of the disc.
By appropriately raising the tab, the user breaks the pre-fracture line, and following the partial or total breaking of the pre-fracture line either a partial or total opening of the container is obtained.
This type of lid exhibits some drawbacks. On opening the container, an erroneous manipulation on the part of the user might result in the tab detaching.
In this situation the user must remedy the partial breakage of the pre-fracture line with the help of a tool, with which he or she can raise the lid at the broken point of the pre-fracture line and subject it to traction in an upwards direction such as to complete the breakage of the pre-fracture line.
During this manoeuvre the user must pay particular attention, as if he or she operates the tool wrongly damage might ensue, such as small cuts to the hands. Further, following the breaking of the line, the detached portion of the lid has to be carefully handled as its profile is especially sharp, with all the drawbacks that ensue.
A third type of lid is described in EP 0 958 179.
This document describes a lid, an edge of which is of a type connected to the lateral flank of the corresponding container.
This lid is interested by a perimeter groove having a U-section, which passes around the lateral flank of the container, on which a pre-fracture line is made, realised on the bottom of the groove, and a weakening line realised in the edge connecting the internal wall of the groove with the central part of the lid.
In order to open the container, to which the lid is associated, the point of a spoon or a further tool is inserted in the groove, using the external wall of the groove as a fulcrum: the layer of metal constituting the lid breaks at the pre-fracture line and thereafter the internal wall of the groove oscillates with respect to the weakening line and orientates towards the axis of the lid.
Though facilitating the opening operation, this type of lid exhibits some drawbacks.
If anomalous pressure builds up inside the container, the pre-fracture line can break even though not solicited by the tool, or following the initial breakage of the pre-fracture line, the lid can be launched violently upwards. In this situation the user can be accidentally struck and injured by the lid.
In a case in which the container falls or is accidentally impacted, the rigidity of the bottom of the can, can cause the involuntary breakage of the pre-fracture line with a consequent loss of seal in the container.
The aim of the present invention is to provide a lid for containers, such as cans and the like, which obviates the above-described drawbacks, in particular made in such a way as to prevent involuntary opening of the respective container and the upwardly-direction projection of the lid.
A further aim is to provide a lid for containers in which simple technical-functional details are actuated such as to enable an increase in the resistance of the lid to mechanical stress phenomena.
A further aim of the invention is to provide a lid made in such a way as to comprise references for facilitating the user when opening the container.
A still further aim of the invention is to provide a lid for containers having contained costs in relation to the advantages it provides.
The above aims are attained by means of the present invention, as it is characterised in the appended claims.
The characteristics of the invention are set out in the following, with reference to the accompanying figures of the drawing, in which:
With reference to the figures, 2 denotes a container which in
The container is closed by means of a metal lid 20 an edge B of which is bent and hooked in a known way to the upper bent edge of the lateral flank 2A of the container 2.
The lid exhibits a groove 10 having a U-section, which borders the lateral flank 2a in a closed-ring progression.
The bottom 10A of the groove exhibits a pre-fracture line 3 and an anti- fracture line 5 which is external of the pre-fracture line 3; a weakening line 4 is realised in the edge C which connects the internal wall 10B of the groove 10 with the central part 20A of the lid.
The pre-fracture line 3 follows the internal wall 10B; at the zone Z the depth of the pre-fracture line 3 is reduced (even zeroed) such as to prevent fracturing of the line 3.
In a diametrically-opposite position with respect to zone Z, a reference notch T is located on the upper surface of the central part 20A of the lid 20.
Owing to the presence of the anti-fracture line 5, the bottom 10A of the groove 10 effectively resists the mechanical stresses; this is due to the increase in its flexibility deriving from the anti-fracture line 5.
It follows that accidental falls of the container 2, or impacts thereon, do not cause even partial breakage of the pre-fracture line 3. In this way the container seal is safeguarded.
In a variant (not illustrated) the depth of the anti-fracture line 5 can be reduced (even zeroed) at zone Z.
To open the container the user inserts a tip of a spoon 50 or another tool into the groove 10 at the position of the notch T; by using the external wall 10C of the groove 10 as a fulcrum a transversal force can be generated on the internal wall 10B of the groove 10 which causes the pre-fracture line 3 to break (
At this point the user slides the tool 50 in the groove 10 in the two directions M1, M2 (
This advantageous aspect is obtainable also in the second embodiment (
The central part 20A of the lid does not detach from the container.
The lid of the invention attains the aims of the invention, as it is conformed such as to ensure seal of the container even following external stresses acting on it, and is such as to prevent its detachment from the body of the container.
Finally, the notch T identifies a point for introduction of the tool in the groove; the fact that the notch T is centrally situation in the pre-fracture line 3 facilitates breakage operations thereof.
The above is intended to be purely by way of non-limiting example, and any technical-functional variants are understood to fall within the ambit of protection as above-described and as claimed herein below.
Number | Date | Country | Kind |
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BO2009A 000701 | Oct 2009 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/IB2010/054879 | 10/28/2010 | WO | 00 | 4/27/2012 |