Patent Description:
For example, in the case of drinks, these can in particular be fizzy or carbonated drinks or beverages, generally with carbon dioxide added and, therefore, the containers discussed here can be containers able to resist pressure, for example, internal pressure of about <NUM> atmospheres (<NUM> psi) or more, for instance up to about <NUM> to <NUM> atmospheres (<NUM> to <NUM> psi) or even more.

The lid according to the present invention is also suitable for making watertight containers for special products, such as seeds, laboratory products, chemical products, or others.

In particular, the description refers to lids, and corresponding containers, or cans, including the lids, advantageously, but not exclusively, made of aluminum, or aluminum alloys, as well as other metal materials, such as iron-based materials, for instance steel or steel-based alloys, tin-based metal materials, or other suitable metals or alloys, or combination thereof, in which a closing cap is provided which hermetically closes a delivery aperture. The closing cap is initially an integral part of the lid and subsequently, when a part is at least partly torn, determines the formation of a delivery aperture, remaining integral with the cap ("stay-on tab"). According to a variant, the closing cap is completely separated from it when opened for delivery ("ring pull").

The present invention concerns lids, and containers equipped with said lids, in which said part, configured as a closing cap with an opening lever, at no time in the tearing and opening, enters inside the container, that is, it concerns lids and containers of the hygienic type, or, in particular, of the non-contaminating type.

The containers according to the present invention, depending on what they have to contain, may have the internal surface made of the metal that constitutes the container, or the internal surface may have a protective film of material consistent and compatible with the content, or of materials which are consistent and compatible with the content and which prevent contact between content and external container.

Documents <CIT> and <CIT> in the name of the Applicant are known, concerning lids and containers provided with such lids to contain a substance, in which there is a closing cap with pull-off opening, which remains integral with the lid once opened (stay-on tab). In these known documents, a rivet is provided that connects an opening lever to the closing cap, which rivet is disposed inside an incision line that defines the closing cap.

Document <CIT> is also known, which describes a lid with a closing cap with pull-off opening, defined by an incision line with an open profile, to obtain a configuration of the "stay-on tab" type, wherein there is an opening lever connected to the closing cap by means of an integral rivet, which is disposed inside the perimeter defined by the incision line.

Furthermore, document <CIT> is also known, which describes a lid with a closing cap with pull-off opening, defined by an incision line with a closed profile, to obtain a completely removable cap. In this case too, a rivet is provided to connect the opening lever to the closing cap, disposed inside the closed profile incision line.

If the substances contained in the containers in question are to be taken by humans or animals, there is a great need to ensure that the closing cap does not enter, even to a small extent, inside the container. This requirement derives from the fact that the external part of the closing cap can contain various contaminants and if it entered the container it could therefore contaminate the contents. Therefore, the problem arises of preventing contamination of the substance inside the container and the necessity arises to make hygienic lids and containers. This is to prevent foreign substances such as dust, dirt, germs, bacteria or other pathogens from being introduced into the product in the container.

This necessity is most urgent in places where the containers are kept, even only temporarily, in the open or in unprotected environments, where the strangest substances can be deposited on the lid. In this case, if, as an indicative example, the container contains a drink or medicine, if the closing cap carries the substances into the container, dangerous conditions can also materialize for the user.

This necessity is also felt in particular in the case of taking pharmaceutical substances, in which the pathological condition of the person or animal taking these substances may not support the presence of said contaminants, pollutants or pathogens. This may also apply to substances used for sport activities or the like, such as for instance sport foods or dietary supplements.

Systems known in the state of the art can suffer from the disadvantage that even a minimal part of the closing cap goes, or faces, although temporarily, toward the inside of the container, at the time of the pull-off opening, thereby creating hygiene and health problems.

Additionally, with known systems there is a limit to the use of complete containers with such lids, as there is no guarantee of hygiene and/or non-contamination. This limit prevents the use of such containers for the transport and/or storage of contaminating material, or of material that must not be contaminated.

Furthermore, with known systems there are limits in the type of content, and therefore such known systems are unsuitable, in certain cases, for the passage of a sufficient quantity of air in the short time when the cap is actuated, which creates turbulence for the liquid at exit.

Another known container lid is described in document <CIT>, in the name of the Applicant.

The lid for containers comprises: a closing cap defined by an incision line and provided with a front portion; an opening lever disposed astride the incision line and comprising a front fulcrum end disposed at the front of the front portion and an intermediate region provided with a flexible tongue attached to the closing cap; a mechanical element configured to mechanically attach the flexible tongue to the closing cap and provided with an upper abutment head; the head is configured to cooperate with the flexible tongue and is delimited perimetrically by an external periphery. The mechanical element is disposed essentially tangent to the front portion of the incision line, and the external periphery of the upper abutment head is aligned orthogonally to the incision line.

Although the lid for containers described in document <CIT> has undoubted advantages and can be considered an evolution with respect to other known lids for containers, the lid can also be improved with regard to the effectiveness of the closing system, for example, with regard to the hygiene and non-contamination of the substance present in the container.

Furthermore, the lid described in this document can be improved with regard to its effectiveness in preventing phenomena of venting/bursting, in particular unintended or explosive venting, which, for example, could occur in the case of containers characterized by a certain internal pressure, for example containers containing a carbonated, sparkling or similar drink, that is, one to which carbon dioxide is generally added. In particular, the phenomenon of "venting", that is, the escape of the gases present in the container, normally occurs when the opening lever is lifted, creating a tension on the incision line, until the latter is broken. At this point, the pressure in the container can be released through the zone that has been fractured; however, until the pressure in the container is released, a certain force is still applied on the opening lever. Once the incision line is broken, it is much easier to open the closing cap, because at this point a shear stress is applied to break the incision line, and not a lifting tension. Therefore, in such containers containing a pressurized gas which has to vent, in the first opening steps, when the gas is released from the container (venting), the gas pressure is added to the traction force exerted by the user on the opening lever. This traction added to the pressure exerted by the gas could lead to an unwanted and premature tearing of the closing cap from the container.

There is therefore a need to perfect a lid for containers which can overcome at least one of the disadvantages of the state of the art.

In particular, one purpose of the present invention is to provide a lid for containers which is equipped with an improved closing system which, when opened, substantially guarantees the hygiene and non-contamination of the substance present in the container, preventing even the smallest part of the closing cap from going inside the container during opening.

Another purpose of the present invention is to provide a lid for containers which allows to greatly limit the phenomena of venting/bursting, in particular unintended or explosive venting, thanks to an effective conformation of the incision line, in particular in the zone where the closing cap of the lid begins to detach, by means of the corresponding opening lever.

The dependent claims describe other characteristics of the invention or variants to the main inventive idea.

In accordance with the above purposes, a lid according to the present invention for a metal container able to contain a substance comprises:.

According to the invention, the protruding portion has, on both sides, segments of the incision line which move away from the mechanical element as far as respective deformation zones, caused by compression of the incision line.

Advantageously, thanks to the particular conformation of the incision line in correspondence with the protruding portion and to the presence of the deformation zones caused by compression which substantially delimit the protruding portion, the lid according to the invention allows to greatly limit the phenomena of venting/bursting, in particular unintended or explosive venting, in particular in the zone where the closing cap of the lid begins to detach, by means of the corresponding flexible opening tongue.

The present invention therefore solves the problem of allowing an adequate release of gases when opening (venting) in pressurized containers for fizzy or sparkling drinks or beverages, e.g. carbonated drinks or beverages, that is, drinks or beverages to which carbon dioxide is generally added, advantageously for internal pressure of about <NUM>,<NUM> atmospheres (<NUM> psi) or more, for instance up to about <NUM> to <NUM> atmospheres (<NUM> to <NUM> psi) or even more. This is because a specific zone is defined, by means of the incision line, which defines where the gas is released. This is very important because the closing cap of the lid described here has an increased area compared to traditional "stay-on tabs" of known conventional lids. The incision line therefore has this protruding portion which, in practice, is widened in correspondence with the mechanical element. The geometry of the segments of the incision line, which move away from the mechanical element as far as respective deformation zones caused by compression made in the metal material that defines the lid, gives an advantageous behavior on the occasion of the first opening when the gas escapes (venting), on one hand preventing the closing cap from being torn and, on the other hand, preventing the "venting" action from continuing to open the closing cap in an unintentional and sometimes even violent way. In this respect, in combination with the geometry of the segments of the incision line, the deformation of the material of the incision line in this zone also plays an important role: the mechanical deformation action obtained by mechanical compression of the thickness of the metal material of the lid in this zone in practice moves material of the thickness into correspondence with the path of the incision line. The effect of this displacement of material caused by compression is that the flow of metal material in the path of the incision line changes, and therefore defines in a desired way a localized resistance to the shearing stress during opening, so that it is possible to control the venting action in a very specific point or zone, but without requiring an excessive increase in the force to be applied which is necessary to pull the opening lever. In other words, thanks to the combination of the geometry of the wide protruding portion, of the segments of the incision line and of the deformation zone caused by compression of the material of the incision line, a desired localized "slowdown" of the opening of the closing cap is obtained during the "venting" operation, ensuring that the gases escape properly, but without tearing or lacerating the closing cap.

In some embodiments, the protruding portion in particular can be substantially rounded in shape and have a width of about <NUM> to about <NUM>.

The protruding portion can advantageously, although not essentially, be in the shape of an arc of a circle and have a radius of curvature of about <NUM> to about <NUM>.

The radius of the protruding portion is greater than the radius of the mechanical element and the profile of the protruding portion continues, as we said, moving away from the mechanical element by means of the segments of the incision line as far as the respective deformation zones of the material, where there is a change in the opening direction, defined by an internal radius, able to prevent on the one hand the closing cap from being torn and, on the other hand, to prevent the venting action from continuing to unintentionally open the closing cap, even violently. This aspect, in combination with the deformation zones of the material in this transition region and the change in the opening direction of the incision line, allows to adequately control the venting action.

In particular, each deformation zone caused by compression can comprise at least a first curvature having a concavity facing toward the outside of the lid and at least a second curvature having a concavity facing toward the inside of the lid. The succession of first and second curvatures can advantageously define the transition and modification in the opening direction of the incision line.

The radius of curvature of the first curvature is about <NUM> to about <NUM>.

The radius of curvature of the second curvature is about <NUM> to about <NUM>.

Each deformation zone can have a diameter of about <NUM> to about <NUM>.

The lid, according to an evolved variant, can also comprise an anti-breaking line positioned around the incision line.

The anti-breaking line is shaped so as to follow the profile of the incision line at least in a zone of the closing cap comprised between a rear flap of the closing cap and the zone of the closing cap where the mechanical element is positioned. Furthermore, each deformation zone can extend beyond the anti-breaking line. The anti-breaking line and the incision line can be connected in proximity to the rear flap of the closing cap by a connecting arc.

The radius of curvature of the connecting arc can be about <NUM> to about <NUM>.

The average distance between the incision line and the anti-breaking line can be about <NUM> to about <NUM>.

The depth of the incision line is preferably greater than the depth of the anti-breaking line.

The lid, in a zone comprised between the incision line and the anti-breaking line, can have a thickness of about <NUM> to about <NUM>.

Moreover, under the incision line, the lid can have a thickness of about <NUM> to about <NUM>.

Furthermore, in correspondence with each deformation zone, the lid can have a thickness of about <NUM> to about <NUM>.

The lid can comprise a reinforcement edge defined by at least a first reinforcement line and by at least a second reinforcement line.

The first reinforcement line can be a closed line which completely surrounds the incision line.

The second reinforcement line can be an open line which partly surrounds the first reinforcement line and comprises, on one side and the other of the incision line, two branches which break substantially at the height of the deformation zone caused by compression of the incision line.

The branches of the second reinforcement line can be divergent with respect to the first incision line.

Moreover, in correspondence with the reinforcement edge, the lid can have a thickness of about <NUM> to about <NUM>.

The minimum distance between the first reinforcement line and the center of the mechanical element is about <NUM> to about <NUM>.

The minimum distance between the anti-breaking line and the center of the mechanical element is about <NUM> to about <NUM>.

The minimum distance between the incision line and the center of the mechanical element can be about <NUM> to about <NUM>.

The mechanical element can be a rivet having an average diameter of about <NUM> to about <NUM>.

Furthermore, the lid can comprise lateral centering ridges, which cooperate with the front lateral edge of the opening lever in order to center it; each of the lateral centering ridges can have a length of about <NUM> to about <NUM>, a width of about <NUM> to about <NUM> and a height of about <NUM> to about <NUM>.

The invention also concerns a container comprising a lid as defined above.

We will now refer in detail to the possible embodiments of the present invention, of which one or more examples are shown in the attached drawings by way of non-restrictive example. The phraseology and terminology used here is for the purpose of non-restrictive example.

In the attached drawings, see in particular <FIG> and <FIG> a lid <NUM> according to the present invention is shown, usable as a lid for a container <NUM> able to contain a substance, for example fluid, liquid, powder, granular or other solid form, in particular a pourable substance, for example substances that can be taken by humans or animals, such as drinks, food substances in general, food supplements, pharmaceutical substances, etc..

For example, the liquid substance can be a drink, such as a carbonated drink, a carbonated soft drink, an alcoholic beverage, fruit juice, tea, infusions, beer, an energizing drink or other.

The container <NUM> can for example be configured as a can for containing drinks or beverages, i.e. canned drinks or beverages. In particular, the container <NUM> might be a can suitable for containing beverages or drinks held under pressure, especially carbonated beverages or drinks. For instance, the container <NUM> can resist to internal pressure of about <NUM>,<NUM> atmospheres (<NUM> psi) or more, for instance up to about <NUM> to <NUM> atmospheres (<NUM> to <NUM> psi) or even more.

Generally, both the lid <NUM> and the container <NUM> can be made of metal, such as for example aluminum or its alloys, or an iron-based metal, in particular steel-based, for instance steel or steel-based alloys, as well as tin-based metal materials, or other suitable metals or alloys, or combination thereof. The materials of the lid <NUM> and container <NUM> could be different from each other. The materials are also consistent and compatible with the substance contained. For example, for carbonated drinks, that is to say, those with added gas or which contain gas caused by fermentation, the lid <NUM> can be, as normally happens, made of aluminum or iron, or their alloys, or other suitable metal materials.

It can also be provided that the internal part of the container <NUM>, and of the lid <NUM>, is covered with a special coating, for example a protective film consistent and compatible with the needs of the content. Protection with materials such as plastic, ceramic or other similar materials may also be provided, depending on the content and/or time it is contained. Advantageously, but not necessarily, the coating is solidly attached to the internal surface of the container <NUM>.

The sizes of the container <NUM> can be similar, in plan, to those of the lid <NUM>, or they can be bigger, just as they can be smaller. Thus, for example the container <NUM> can have the same diameter as the lid <NUM>, or it can have a larger diameter, or a smaller diameter.

Preferably, the lid <NUM> according to the present invention is the easy-open type.

The lid <NUM> comprises a closing cap, or panel <NUM>, that can be opened by tearing and defined by at least an incision or pre-cut line <NUM>, able to allow the closing cap <NUM> to be lifted and at least partly torn. Advantageously, the incision line <NUM> can have an overall open profile, so that the closing cap <NUM>, once lifted from the lid <NUM>, can still remain connected to it ("stay-on tab").

The lid <NUM> also comprises an opening lever, or tab <NUM>, disposed astride the incision line <NUM> and comprising a front fulcrum end <NUM> and an intermediate region <NUM> provided with a flexible tongue <NUM> attached to the closing cap <NUM>.

The lid also comprises a mechanical element <NUM>, for example a rivet or suchlike, located in proximity to the incision line <NUM>, configured to mechanically attach the flexible tongue <NUM> to the closing cap and configured to cooperate with the flexible tongue <NUM>.

At the front, in the zone where the closing cap <NUM> begins to lift and tear, the incision line <NUM> has a portion <NUM> protruding toward the outside, toward the front fulcrum end <NUM> of the opening lever <NUM>.

According to the invention, the protruding portion <NUM> has at both sides segments <NUM> of the incision line <NUM> which move away from the mechanical element <NUM> as far as respective deformation zones <NUM> caused by compression of the incision line <NUM> (see for example <FIG>, <FIG>, <FIG>).

In this way it is possible to make a protruding portion <NUM> of rounded and widened shape which, in combination with the deformation zones <NUM> provided at the end of the segments <NUM> made on the incision line <NUM>, greatly limits the phenomena of venting/bursting, in particular unintended or explosive venting of known lids.

The incision line <NUM> can delimit a delivery aperture <NUM> on the perimeter, see for example <FIG>, which is normally closed by the closing cap <NUM> and through which it is possible to deliver or pour the substance contained in the container <NUM>.

Around the delivery aperture <NUM>, the lid <NUM> has a closing wall <NUM>, for example of a circular shape, like the container <NUM> with which it can be associated. The lid <NUM> can also be delimited by an annular peripheral rib, or bead, <NUM>. Externally to the annular peripheral rib, or bead, <NUM> there is an edge <NUM>, raised with respect to the plane of the lid <NUM> and to the closing wall <NUM>.

The closing cap <NUM> can be lifted or detached from the lid <NUM>, generating the delivery aperture <NUM> as above.

It is possible to provide that the lid <NUM> is the "stay-on tab" type. For this purpose, according to some possible embodiments described here, the incision line <NUM> can be interrupted, that is, it can have an open profile, for example of at least partly curved shape, or in any case with a mixed curvilinear/linear development. The fact that the incision line <NUM> can be interrupted, that is, it may have an open profile, means that the closing cap <NUM>, once lifted from the lid <NUM>, can still remain connected to it ("stay-on tab"), without the risk of being dispersed in the environment, and thus preventing pollution.

It is possible to provide that, due to the way the development of the incision line <NUM> is made, the closing cap <NUM>, when lifted, will not easily detach from the rest of the lid <NUM>, for example by breaking, due to the presence of terminal branches <NUM>, for example shaped like curls. The terminal branches <NUM> are defined by segments of the incision line <NUM> curved toward the outside, which advantageously also perform an elastic function of absorbing stress, preventing the closing cap <NUM> from breaking.

Moreover, with reference for example to <FIG>, the underside surface <NUM> of the closing cap <NUM> can be provided with indications, signs, logos or other advertising means for promotional purposes. Such indications may be engraved, printed or obtained by other means on said underside surface <NUM>.

The incision line <NUM> is substantially a pre-incised or pre-cut line that defines a predetermined breaking profile, along which the closing cap <NUM> can be torn and detached. The incision line <NUM> can be made according to techniques known in the state of the art. The incision line can, for example, be doubled, the incision line <NUM> described here acting as the main one, more internal, and providing an anti-breaking line <NUM>, more external, as can be seen in the attached drawings and as described in detail below.

The opening lever <NUM> can be disposed astride the incision line <NUM>, partly above the closing cap <NUM> and partly outside it. The opening lever <NUM> can have, at one end, a fulcrum part on the lid <NUM>, and at an opposite end it can be lifted. In an intermediate position, the opening lever <NUM> is attached to the closing cap <NUM>.

The opening lever <NUM> can be disposed aligned along a median axis A of the lid <NUM>, for example in order to improve the opening effect.

The opening lever <NUM> can also comprise a rear drive end <NUM>, opposite the front fulcrum end <NUM>. In possible implementations, the rear drive end <NUM> can comprise a gripping ring <NUM> which can be easily gripped by the user to lift and rotate the opening lever <NUM>, pivoting on the front fulcrum end <NUM>.

The front fulcrum end <NUM> can be disposed externally to the incision line <NUM>. In this way, the opening lever <NUM>, when rotated around the front fulcrum end <NUM>, can press on a point outside the incision line <NUM>. The front fulcrum end <NUM> can be configured to essentially define a single pivoting point of the opening lever <NUM>.

The mechanical element <NUM>, as we said, is configured to mechanically attach or connect the flexible tongue <NUM> to the closing cap <NUM>, therefore substantially it is a mechanical element to clamp the flexible tongue <NUM> on the closing cap <NUM>. In particular, the mechanical element <NUM> is provided inside the incision line <NUM>. The mechanical clamping element <NUM> can be made of the same material as the lid <NUM>. The mechanical element <NUM> can be shaped for example with an essentially circular shape, having a plan profile with a certain radius.

In accordance with other possible implementations, the mechanical element <NUM> can be a solid rivet, that is, a flat-headed nail, pin or bolt, truncated cone shaped or hemispherical, used for joining metal elements, but it goes without saying that these variants require different production cycle times.

Or, in other possible implementations, the mechanical element <NUM> can be a hollow rivet, that is, a joining element similar to a solid rivet, drilled in the middle and in the shape of an eyelet, generally formed by a double-headed nail. Typically, a manufacturing process of the lid <NUM> can provide to mold a simple lid from a roll of aluminum or its alloys, generally aluminum alloys with magnesium, such as for example typically <NUM>-H48, or based on iron or ferrous alloy, in particular steel, for example mild steel or stainless steel, for example tin-plated or in any case coated, or not.

In particular, the mechanical element <NUM> can be a rivet having an average diameter of about <NUM> to about <NUM>.

The incision line <NUM>, as we said, comprises a protruding portion <NUM> with a rounded and widened shape, for example the protruding portion <NUM> can be in the shape of a circular arc or suchlike. Preferably, the protruding portion <NUM> has a width W1 of about <NUM> to about <NUM>. It has been found in experiments that this value is optimal for counteracting the phenomena of venting/bursting, in particular unintended or explosive venting when opening the container <NUM>.

Moreover, in order to further improve this limiting effect, the protruding portion <NUM> can be made in the shape of an arc of a circle and can have a radius of curvature of about <NUM> to about <NUM>.

Advantageously, the radius of the protruding portion <NUM> is greater than the radius of the mechanical element <NUM> and the profile of the protruding portion <NUM> continues, as we said, moving away from the mechanical element <NUM> by means of the segments <NUM> of the incision line <NUM>, up to the respective deformation zones <NUM> of the material, where there is a change in the opening direction, defined by an internal radius, able to prevent, on the one hand, the closing cap <NUM> from being torn and, on the other hand, the venting action from continuing to unintentionally open the closing cap <NUM>, also in a violent way. This aspect, in combination with the deformation zones <NUM> of the metal material in this transition region and the change of the opening direction of the incision line <NUM>, allows to adequately control the venting action.

In particular, each of the deformation zones <NUM> which substantially delimit the protruding portion <NUM> can comprise at least a first curvature <NUM> having a concavity facing toward the outside of the lid <NUM> and at least a second curvature <NUM> having a concavity facing toward the inside of the lid <NUM>. This sequence of first <NUM> and second curvature <NUM> can advantageously define the transition and change in the opening direction of the incision line <NUM>.

An optimal value for the radius of curvature of the first curvature <NUM> can be about <NUM> to about <NUM>.

An optimal value for the radius of curvature of the second curvature <NUM> can be about <NUM> to about <NUM>.

The deformation zone <NUM> can be obtained for example by means of mechanical compression of the material, in particular punching, riveting or coining. The diameter D1 of the deformation zone <NUM>, see <FIG>, can for example be about <NUM> to about <NUM>.

In addition to the incision line <NUM>, the lid <NUM> can comprise an anti-breaking line <NUM> positioned around the incision line <NUM>. The anti-breaking line <NUM> can be shaped so as to follow the profile of the incision line <NUM>, at least in a zone of the closing cap <NUM> comprised between a rear flap <NUM> of the closing cap <NUM> and the zone of the closing cap <NUM> where the mechanical element <NUM> is positioned.

The anti-breaking line <NUM> substantially has the function of increasing the stability of the lid <NUM> and making it easier to open the closing cap <NUM>.

The anti-breaking line <NUM> and the incision line <NUM> are connected in proximity to the rear flap <NUM> of the closing cap <NUM> by means of the terminal branches <NUM>.

The incision line <NUM> and the anti-breaking line <NUM> are also shown in the sections of <FIG>.

The incision line <NUM> can be made for example by means of a converging incision, that is, for example, V-shaped.

The average distance X1 between the incision line <NUM> and the anti-breaking line <NUM> can be, for example, about <NUM> to about <NUM>. The average distance X1 proved to be optimal to ensure stability of the lid <NUM> by means of the anti-breaking line <NUM> and at the same time a convenient opening step of the closing cap <NUM> along the incision line <NUM>.

The depth Z1 of the incision line <NUM> can be greater than the depth Z2 of the anti-breaking line <NUM>. In this way, during the lifting of the closing cap <NUM>, the wall <NUM> of the lid <NUM> has a lower thickness below the incision line <NUM> with respect to the thickness under the anti-breaking line <NUM>.

In particular, the depth Z1 of the incision line <NUM> is about <NUM> greater than the depth Z2 of the anti-breaking line <NUM>.

The thickness Z3 of the lid <NUM> under the incision line <NUM> can be about <NUM> to about <NUM>.

Moreover, the thickness Z4 of the lid <NUM>, in a zone comprised between the incision line <NUM> and the anti-breaking line <NUM> is about <NUM> to about <NUM>.

The thickness Z5 of the lid <NUM> in correspondence with the deformation zone <NUM> can be of about <NUM> to about <NUM>.

The deformation zone <NUM>, as can be seen from a comparison of <FIG>, can also extend beyond the anti-breaking line <NUM>.

The minimum distance Y1, see <FIG>, between the anti-breaking line <NUM> and the center of the mechanical element <NUM> can be about <NUM> to about <NUM>.

The minimum distance Y2 between the incision line <NUM> and the center of the mechanical element <NUM> can be about <NUM> to about <NUM>.

The lid <NUM> can also comprise a reinforcement edge <NUM> defined by at least a first reinforcement line <NUM> and by at least a second reinforcement line <NUM>. The reinforcement lines <NUM> and <NUM> are curved and at least partly follow the shaping of the incision line <NUM> and possibly of the anti-breaking line <NUM>, see in particular <FIG> and <FIG>. The reinforcement lines <NUM> and <NUM> can be for example incisions, ribs or other.

In particular, the first reinforcement line <NUM> can be a closed line that completely surrounds the incision line <NUM>. It can have a connecting arc <NUM> at the top. An optimal value of the radius of curvature of the connecting arc <NUM> can be about <NUM> to about <NUM>.

The second reinforcement line <NUM> can be an open line which partly surrounds the first reinforcement line <NUM> and comprises, on one side and the other of the incision line <NUM>, two branches <NUM> which are interrupted substantially at the height of the deformation zone <NUM> of the incision line <NUM>.

The interruption of the reinforcement line <NUM> allows the wall <NUM> of the lid <NUM> to remain substantially unchanged in the zone where the flexible tongue <NUM> will be applied, that is, so that the wall <NUM> is substantially flat and there are no slopes resulting from incisions or other.

The branches <NUM> of the second reinforcement line <NUM> can also diverge from the first reinforcement line <NUM>. In essence, as can be observed for example in <FIG> or <FIG>, the free end of the branches <NUM> is the furthest point of the branches <NUM> with respect to the first reinforcement line <NUM>.

The divergence of the branches <NUM> can be provided in order to have a greater transition zone from the first reinforcement line <NUM> to the second reinforcement line <NUM>, especially in a position close to the deformation zone <NUM>.

The thickness of the lid <NUM> in correspondence with the reinforcement edge <NUM> can be of about <NUM> to about <NUM>.

The minimum distance Y3 between the first reinforcement line <NUM> and the center of the mechanical element <NUM>, see in particular <FIG>, can be about <NUM> to about <NUM>.

The lid may also comprise lateral centering ridges <NUM>, which cooperate with the front lateral edge of the opening lever <NUM> in order to center it. Each of the lateral centering ridges <NUM> can have a parallelepiped shape having a length of about <NUM> to about <NUM>, a width of about <NUM> to about <NUM> and a height of about <NUM> to about <NUM>.

The lid <NUM> can also comprise bosses <NUM>, see <FIG>, to position the opening lever <NUM>, or to correctly position the opening lever <NUM> with respect to the plane of the lid <NUM>. The bosses <NUM> are made protruding from the closing cap <NUM> toward the opening lever <NUM> above.

For example, two bosses <NUM> can be provided, made under the opening lever <NUM> and symmetrical with respect to the median axis A.

The lid <NUM> can also be equipped with a central boss <NUM>, made protruding from the closing cap <NUM>, which cooperates with the gripping ring <NUM> of the opening lever <NUM>.

In particular, the central boss <NUM> can be disposed along the median axis A and is centered inside the hole of the gripping ring <NUM>. The central boss <NUM> has been designed to improve and guarantee the exact axial centering of the opening lever <NUM>.

In the sequence of drawings from <NUM> to <NUM>, an opening sequence of the lid <NUM> is shown, by way of non-restrictive example.

The flexible tongue <NUM> is gripped by the user and rotated upward and toward the outside of the container <NUM>. After a certain inclination of the flexible tongue <NUM>, the closing cap <NUM> begins to detach from the lid <NUM>, along the incision line <NUM>, see <FIG>. In particular, the resistance of the mechanical element <NUM> causes the initial detachment of the closing cap <NUM>, which is immediately lifted by the initial tear, in precise correspondence with the incision line <NUM>, in particular with its protruding portion <NUM>, preventing even the minimum part or flap of the closing cap <NUM> from going inside the container <NUM>, contaminating the substance contained therein. In other words, the first zone of the closing cap <NUM> which detaches from the rest of the lid <NUM> is the zone close to the protruding portion <NUM> of the incision line <NUM>. By pulling the flexible tongue <NUM> in the opposite direction with respect to the lifting rotation, the closing cap <NUM> is pulled in the opposite direction with respect to the protruding portion <NUM> until it reaches the situation shown in <FIG>. Thus, a hygienic lid can be advantageously obtained.

By using the lid <NUM>, the effort necessary to lift the closing cap <NUM> along the incision line <NUM>, as well as being much lower compared with containers with a hygienic cap, that is, a cap that opens toward the outside, as known in the state of the art, is also much better distributed and exploited, so that the operation leads to a uniform, precise, repeatable and reliable detachment.

Furthermore, in a first opening step, thanks to the provision of the protruding portion <NUM> substantially delimited by the deformation zones <NUM> and with the segments <NUM> moving away from the mechanical element <NUM>, the phenomena of venting/bursting, in particular unintended or explosive venting are limited which, instead, can occur when opening containers with lids known in the state of the art.

It is clear that modifications and/or additions of parts may be made to the lid for containers as described heretofore, without departing from the field and scope of the present invention.

Claim 1:
Lid for a metal container (<NUM>) able to contain a substance, comprising:
- a closing cap (<NUM>) defined by at least one incision or pre-cut line (<NUM>), able to allow the closing cap to be lifted and at least partly torn,
- an opening lever (<NUM>) disposed astride the incision line (<NUM>) and comprising a front fulcrum end (<NUM>) and an intermediate region (<NUM>) provided with a flexible tongue (<NUM>) attached to the closing cap (<NUM>),
- a mechanical element (<NUM>) located in proximity to the incision line (<NUM>), configured to mechanically attach the flexible tongue (<NUM>) to the closing cap (<NUM>) and configured to cooperate with said flexible tongue (<NUM>),
- said incision line (<NUM>) having at the front, in the zone where the closing cap (<NUM>) starts to be lifted and torn, a portion (<NUM>) protruding outward, toward the front fulcrum end (<NUM>) of the opening lever (<NUM>),
wherein said protruding portion (<NUM>) has, on both sides, segments (<NUM>) of the incision line (<NUM>) which move away from said mechanical element (<NUM>) as far as respective deformation zones (<NUM>), caused by compression made in the metal material that defines the lid and in the material of the incision line (<NUM>), wherein the radius of the protruding portion (<NUM>) is greater than the radius of the mechanical element (<NUM>) and the profile of the protruding portion (<NUM>) continues moving away from the mechanical element (<NUM>) by means of said segments (<NUM>) as far as the respective deformation zones (<NUM>) of the material, where there is a change in the opening direction of the incision line (<NUM>), defined by an internal radius.