EP3938291A1

EP3938291A1 - Safety ring for containers

Info

Publication number: EP3938291A1
Application number: EP20707841.1A
Authority: EP
Inventors: William SARACCHI
Original assignee: Femm SpA
Current assignee: Femm SpA
Priority date: 2019-03-11
Filing date: 2020-03-03
Publication date: 2022-01-19
Anticipated expiration: 2040-03-03
Also published as: IT201900003483A1; ES2944289T3; WO2020183287A1; EP3938291B1

Abstract

A safety ring (100) for closing a container (105), wherein said container (105) comprises an opening (110), an annular flange (120) that surrounds and protrudes radially from said opening (110) and a lid (125) capable of closing said opening (110) and having a perimeter edge (130) able to rest on the annular flange (120), wherein the safety ring (100) comprises: a curved band (140) which extends about a predetermined central axis (X) and which exhibits a first and a second end portion (160, 165) overlapped on each other, a clamping device (195) operable to make said end portions (160, 165) slide in a circumferential direction, keeping them in mutual overlap, between an open-ing configuration, wherein the overlapping of said end portions (160, 165) is minimal and the diameter of the curved band (140) relative to the central axis (X) is maximum, and a closing configuration, wherein the overlap of said end portions (160, 165) is maximum and the diameter of the curved band (140) is minimal, and wherein said curved band (140) exhibits a lateral strip (155), substantially cylindrical in shape, able to surround the annular flange (120) of the container (105), a first circumferential edge (145) projecting radially inward with respect to the lateral strip (155), which is adapted to be overlapped on the perimeter edge (130) of the lid (125), and a second circumferential edge (150) able to be folded under the annular flange (120) of the container (105).

Description

SAFETY RING FOR CONTAINERS

Technical Field

The present invention relates to a safety ring for closing containers, typically metal con tainers such as, for example, buckets, bins or drums, which comprise an opening and an annular flange that surrounds and radially projects from said opening.

Prior art

As is known, containers of the type outlined above can be used for the packaging and sale of various products, mainly in liquid form, including dangerous, harmful and/or pol luting products such as acids, paints, thinners and the like.

After being filled with the product to be packaged, these containers are closed with a relevant lid, which occludes the opening and has a perimeter edge resting on the annu lar flange.

A safety ring can be used to mutually constrain the lid to the container.

Traditionally, this safety ring is made starting from a curved band, typically made of metal material which extends circumferentially about a predetermined central axis.

The two end portions of the curved band are mutually overlapped and firmly fixed to one another, e.g. by welding, so as to obtain a closed ring having a diameter corresponding to the annular flange of the container.

Subsequently, one of the circumferential edges of the ring is deformed so as to make it project radially inward, i.e. towards the central axis of the band, giving the band a sub stantially square or L-shaped cross section.

At this point, the ring is fitted onto the container, taking care so that the projecting cir cumferential edge rests on the perimeter edge of the lid, after which the opposite cir cumferential edge is deformed and folded under the annular flange of the container.

To allow the opening of the container, predefined fracture lines are made in advance on the band, which allow users to break and remove the safety ring.

This solution has the advantage of obtaining very stable and secure locking of the lid but has the drawback of no longer being able to re-close the container after the safety ring has been removed.

To solve this drawback, open safety rings have been proposed in the past, whose end portions are separated and connected to one another by means of a clamping device, which is able to move them towards and away from one another in the circumferential direction, respectively reducing or increasing the total diameter of the safety ring.

In this way, by operating the clamping device, users can effectively widen the safety ring, in order to allow the removal of the lid and the opening of the container and, vice versa, reposition the lid and clamp the safety ring again, in order to guarantee the re closure of the container.

However, not all of these re-closable safety rings are always able to provide sufficiently stable and secure locking of the lid in the most critical conditions, e.g. in the event of the container accidentally falling from heights greater than a metre.

Disclosure of the invention

In light of the above, an object of the present invention is that of making available a re- closable safety ring that can guarantee more stable and secure locking of the lid onto the container.

Another object is that of achieving the mentioned objective within the context of a sim ple, rational and relatively cost-effective solution.

These and other objects are reached thanks to the characteristics of the invention as set forth in the independent claim 1. The dependent claims outline preferred and/or par ticularly advantageous aspects of the invention.

In particular, an embodiment of the present invention provides a safety ring for closing a container, wherein said container comprises an opening, an annular flange that sur rounds and radially projects from said opening and a lid adapted to close said opening and having a perimeter edge adapted to rest on the annular flange, wherein the safety ring comprises:

- a curved band which extends about a predetermined central axis and which ex hibits a first and a second end portion overlapped on each other,

- a clamping device operable to make said end portions slide in a circumferential direction, keeping them in mutual overlap, between an opening configuration, wherein the overlapping of said end portions is minimal and the diameter of the curved band relative to the central axis is maximum, and a closing configuration, wherein the overlapping of said end portions is maximum and the diameter of the curved band is minimal, and

wherein said curved band exhibits a lateral strip, substantially cylindrical in shape, able to surround the annular flange of the container, a first circumferential edge projecting radially inward with respect to the lateral strip, which circumferential edge is adapted to be overlapped on the peripheral edge of the lid, and a second circumferential edge able to be folded under the annular flange of the container.

Thanks to the presence of the clamping device, this safety ring can be advantageously opened and closed various times, guaranteeing the possibility to re-close the container also after the first opening.

On the other hand, as the two end portions of the curved band are mutually overlapped, this safety ring is rather rigid and stable.

In particular, the strain that tends to open the safety ring is not only discharged onto the clamping device but is also transmitted to the curved band, especially through the mu tually overlapped end portions.

In this way, the safety ring is rather strong and able to provide rather solid locking of the lid onto the container also when it is subjected to critical strain, e.g. in the event of a fall. Another important advantage of this situation consists of the fact that the first application of the safety ring can take place very quickly and can be easily automated, as it does not require manual intervention on the clamping device but only requires the safety ring to be inserted onto the container and the second end edge of the curved band to be folded under the annular flange.

According to a preferred aspect of the invention, the first circumferential edge of the curved band can be folded into a curl and have a cross section, afforded relative to a section plane containing the central axis of the curved band, of a substantially circular or spiral shape, or at least an arc of a circle or an arc of a spiral.

Thanks to this solution, the first circumferential edge of the safety ring defines a sort of entirely hollow perimeter bead which, in the event of impacts, can be deformed (e.g. crushed), absorbing part of the mechanical energy that would otherwise be transmitted to the container, preserving and increasing the safety of the closure.

According to another aspect of the invention, this first circumferential edge can exhibit a first portion that extends at the first end portion of the curved band and a second portion that extends at the second end portion of the curved band, wherein said first portion of the first circumferential edge can be slidably inserted into the second portion.

In this way, the clamping ring acquires great strength and great rigidity, especially in the radial direction, without however preventing the mutual sliding of the two end portions in the circumferential direction and, therefore, without jeopardising the operation and ad vantages of the clamping device.

A further aspect of the invention envisages that the first end portion of the curved band can be devoid of the second circumferential edge.

In other words, the first end portion of the curved band can have a notching, i.e. a shap ing, that reduces the height with respect to the other areas of the curved band and, in particular, with respect to the height of the second end portion.

In this way, in the mutual overlapping stretch between the two end portions, the lower circumferential edge of the safety ring will however have a single thickness, simplifying the folding thereof under the annular flange of the container.

Another embodiment of the present invention makes available a container comprising an opening, an annular flange that surrounds and projects radially from said opening, a lid adapted to close said opening and having a perimeter edge adapted to rest on the annular flange, and a safety ring, wherein said safety ring comprises:

- a curved band which extends about a predetermined central axis and which ex hibits a first and a second end portion overlapped on each other, and

Taking advantage of the new safety ring, this embodiment of the invention has the ad vantage of providing a container which, although being openable and closable various times, is rather solid and strong.

Obviously, all the characteristics of the safety ring that have been outlined above are al so considered applicable to the container according to this embodiment of the invention. The invention finally makes available a method for closing a container, wherein said container comprises an opening, an annular flange that surrounds and projects radially from said opening and a lid that closes said opening and has a perimeter edge resting on the annular flange, wherein said method comprises the steps of:

- preparing a safety ring comprising:

a curved band which extends about a predetermined central axis and which exhibits a first and a second end portion overlapped on each other, and a clamping device operable to make said end portions slide in a circumfer ential direction, keeping them in mutual overlap, between an opening configura tion, wherein the overlapping of said end portions is minimal and the diameter of the curved band relative to the central axis is maximum, and a closing configura tion, wherein the overlapping of said end portions is maximum and the diameter of the curved band is minimal,

wherein said curved band exhibits a lateral strip, substantially cylindrical in shape, a first circumferential edge projecting radially inward with respect to the lateral strip and a second circumferential edge,

- applying said safety ring to the container so that the lateral strip of the curved band surrounds the annular flange of the container and the first circumferential edge is overlapped on the perimeter edge of the lid, and

- folding the second circumferential edge of the curved band under the annular flange of the container.

This embodiment substantially achieves the same advantages outlined above, in partic ular that of allowing a rather stable and secure closure of the container, while allowing it to be opened and re-closed various times.

Obviously, also in this case, all the characteristics of the safety ring that have been out lined above are also considered applicable to the method according to this embodiment of the invention.

According to a preferred aspect of the method, the step of folding the second circumfer ential edge of the curved band can be performed while the end portions of the curved band are in the closing configuration.

Thanks to this solution, the step of folding the second circumferential edge is simpler and safer. According to another aspect of the method, the step of folding the second circumferen tial edge of the curved band can be obtained by rolling or crimping.

Rolling is a process that can use one or more rollers, to each of which a revolution movement about the central axis of the curved band is imparted and contextually a ra dial movement from the outside towards the inside, so that they come into contact and roll against the second circumferential edge and push the axis of revolution, folding it under the annular flange of the container.

Crimping is a process that can use a plurality of jaws that are distributed circumferential ly around the safety ring and that are moved radially towards the central axis (without a revolution movement), so as to simultaneously enter into contact with the second cir cumferential edge and push it from the outside towards the inside, folding it under the annular flange of the container.

These processes have the advantage of allowing the effective folding of the second cir cumferential edge of the safety ring, guaranteeing very stable and precise locking of the lid onto the container.

Brief description of the drawings

Further features and advantages of the invention will be more apparent after reading the following description provided by way of non-limiting example, with the aid of the ac companying drawings.

Figure 1 is a view from above of a container closed by means of a safety ring according to an embodiment of the present invention.

Figure 2 is the section ll-ll of Figure 1.

Figure 3 is an enlarged detail of Figure 2.

Figure 4 is the detail of Figure 3 shown after the folding step of the second circumferen tial edge of the safety ring.

Figure 5 is a front view of the safety ring of Figure 1 shown on an enlarged scale.

Figure 6 is a view from above of the safety ring of Figure 5.

Figure 7 is the view indicated by VII in Figure 6.

Figure 8 is the section VIII-VIII of Figure 7, shown on an enlarged scale.

Figure 9 is the section IX-IX of Figure 6.

Figure 10 is the section X-X of Figure 6.

Figure 1 1 is the detail of Figure 10 shown after the safety ring has been coupled to the container and its second circumferential edge has been folded under the annular flange of the container itself.

Detailed description

From the appended figures, a safety ring 100 can be seen for the closure of a container 105, for example but not necessarily a bin, a bucket or a drum.

The container 105 can be used to contain products in liquid or at least fluid form, e.g. dangerous, harmful and/or polluting products, such as acids, paints, thinners and the like.

The container 105, which can be made of metal, generally comprises an opening 1 10 through which it can be filled and emptied.

For example, the container 105 can have a side wall 1 15 of a substantially cylindrical or truncated cone shape, which is closed at the bottom by a bottom wall (not illustrated) and has an upper circumferential edge that defines the opening 1 10.

The opening 1 10, which can have a circular perimeter, is coaxially surrounded by an annular flange 120, which projects radially from the side wall 1 15 towards the outside of the opening 1 10.

The annular flange 120 can be obtained by turning back the upper circumferential edge of the side wall 1 15.

A lid 125 can be applied to the container 105, also made of metal material, which is adapted to close the opening 110 and is provided with a perimeter edge 130 that rests on the annular flange 120.

Although in the appended figures, the perimeter edge 130 has been represented per fectly flat, in many other embodiments, the perimeter edge 130 can also be turned back, so as to embrace at least partially the annular flange 120, sometimes also being wrapped around it at its most external diameter.

The safety ring 100 is used to firmly lock the lid 125 to the container 105.

The safety ring 100 comprises a curved band 140, preferably made of metal, which is curved so as to extend in a ring arrangement about a predetermined central axis X.

As illustrated in Figure 3, in a parallel direction to the central axis X, the curved band 140 comprises a first circumferential edge 145, a second circumferential edge 150 and a lateral strip 155, substantially cylindrical in shape, which is interposed between the first circumferential edge 145 and the second circumferential edge 150. The second circumferential edge 150 can be initially conformed like a simple extension of the lateral strip 155, i.e. as a further cylindrical strip or possibly a truncated cone shaped strip that extends from the lateral strip away from the first circumferential edge 145.

The first circumferential edge 145 is shaped so as to project radially from the lateral strip 155 towards the central axis X.

For example, the first circumferential edge 145 can be folded into a curl towards the in side of the lateral strip 155 and, preferably, towards the second circumferential edge 150.

In this way, the cross section of the first circumferential edge 145, performed with re spect to a section plane containing the central axis X of the curved band 140, exhibits a substantially circular or spiral shape, e.g. an arc of a circle or an arc of a spiral, similar to that of an open ring.

More generally, this curling of the first circumferential edge 145 gives the overall cross section of the curved band 140 a substantial P shape.

As illustrated in Figure 9, the curved band 140 can also exhibit one or more notches 135, which can be afforded in the form of projections that derive from the inner surface of the second circumferential edge 150 towards the central axis X.

These notches 135, which can be obtained by the local deformation of the curved band 140, can be distributed about the central axis X so as to be angularly equidistant.

For example, the safety ring 100 can comprise three notches 135 separated by a 120° angle from one another (see Fig.1 ).

Thanks to this solution, the lid 125 can be preliminarily coupled to the safety ring 100, with its own perimeter edge 130 that remains axially locked between the first circumfer ential edge 145 of the curved band 140 and the notches 135.

To obtain this effect, the axial distance that separates each notch 135 from the first cir cumferential edge 145 is generally greater than the thickness of the perimeter edge 130 of the lid 125, and the minimum radial distance that separates each notch 135 from the central axis X is less than the maximum radius of said perimeter edge 130.

In this way, the lid 125 and the safety ring 100 can be applied to the container 105 with a single operation.

Flowever, it is not excluded that, in other embodiments, the notches 135 can be missing and/or that the safety ring 100 is applied to the container 105 after the latter has been closed with the lid 125.

In any case, the safety ring 100 is coaxially inserted onto the opening 1 10 of the con tainer 105, so that the first circumferential edge 145 overlaps on the annular flange 120, still resting on the perimeter edge 130 of the lid 125, as shown in Figure 3.

In this position, the lateral strip 155 of the safety ring 100 coaxially surrounds the annu lar flange 120, whereas the second circumferential edge 150 descends and exceeds the lower generatrices of the same annular flange 120 at the bottom.

Then, the second circumferential edge 150 is deformed and folded radially inwards, i.e. towards the central axis X, so as to bring it under and against the annular flange 120, so that the safety ring 100 is clamped onto the container 105 and firmly locks the latter to the lid 125 as shown in Figure 4.

This folding preferably affects the entire perimeter extension of the second circumferen tial edge 150 and can be obtained by rolling or crimping.

Rolling can also envisage using one or more rollers, to each of which a revolution movement about the central axis X is imparted and contextually a movement in the ra dial direction from the outside towards the inside, so that each of them first comes into contact and starts to roll against the second circumferential edge 150 and, then, pushes it towards the central axis X, folding it under the annular flange 120.

Crimping can envisage using a plurality of jaws that are distributed circumferentially around the safety ring 100 and that are then moved radially towards the central axis X (without a revolution movement), so as to simultaneously enter into contact with the second circumferential edge 150 and then push it from the outside towards the inside, folding it under the annular flange 120.

Returning to the safety ring 100, the curved band 140 has, in the circumferential direc tion, two opposite end portions, of which one first end portion 160 and a second end portion 165, which can be seen in Figures 7 and 8.

The first and the second end portion 160 and 165 are mutually overlapped, laterally flanking and preferably in contact with one another, so that the curved band 140 still de fines a closed ring about the central axis X.

The first and the second end portion 160 and 165 are not fixed to one another but are free to slide mutually in the circumferential direction, increasing or reducing the mutual overlapping zone and, therefore, varying the diameter of the safety ring 100.

To guide this sliding, the first circumferential edge 145 of the curved band 140 may ex hibit a first portion 170 which extends along the first end portion 160 and a second por tion 175 which extends along the second end portion 165 and, preferably, for the entire remaining circumferential extension of the curved band 140.

As illustrated in Figure 10, the first portion 170 can have a cross section (i.e. with re spect to a sectional plane containing the central axis X) having a smaller diameter with respect to the diameter of the cross section of the second portion 175 and can be slida bly inserted into the latter.

Thanks to this coupling, the first and the second end portion 160 and 165 of the curved band 140, while being able to slide mutually in the circumferential direction, are firmly constrained to one another, providing the safety ring 100 with high resistance and rigidi ty-

Also the lateral strip 155 of the curved band 140 can comprise a first portion 180 that extends at the first end portion 160 and a second portion 185 that extends at the second end portion 165, where the first portion 180 can be overlapped flanking on the inner side of the second portion 185.

In other words, the extrados surface of the first portion 180 can be turned towards, and preferably be in contact with, the intrados surface of the second portion 185.

Preferably, the first end portion 160 of the curved band 140 is however devoid of the second circumferential edge 150, i.e. of the appendage of the lateral strip 155 which is adapted to be folded under and in contact with the annular flange 120 of the container 105.

In other words, the second circumferential edge 150 can extend along the second end portion 165 and, preferably, for the entire remaining extension of the curved band 140, except at the first end portion 160, where the second circumferential edge 150 is absent or interrupted.

From another point of view, the first end portion 160 can exhibit a notching 190, i.e. a shaping, that reduces the height with respect to the other areas of the curved band 140 and, in particular, with respect to that of the second end portion 165 (see Fig.10).

In this way, the first end portion 160 of the curved band 140 has substantially no ap pendage that extends below the annular flange 120 of the container 105. Thanks to this solution, in the portion of mutual overlap between the two end portions 160 and 165, the second circumferential edge 150 of the safety ring 100 is only defined by the second end portion 165, simplifying the folding thereof under the annular flange 120 of the container 105 (see Fig.1 1 ).

As illustrated in Figures 5 and 6, the safety ring 100 finally comprises a clamping device 195, which can be operated, preferably manually, to make the end portions 160 and 165 of the curved band 140 slide circumferentially, keeping them mutually overlapping, in order to increase or reduce the overall diameter of the curved band 140 with respect to the central axis X.

In particular, the clamping device 195 may be adapted to make the end portions 160 and 165 slide between an opening configuration (not shown), in which the overlapping of said end portions 160 and 165 is minimal and the diameter of the curved band 140 is maximum, and a closing configuration (shown in the figures), wherein the overlapping of said end portions 160 and 165 is maximum and the diameter of the curved band 140 is minimal.

It is pointed out herein that the terms“maximum” and“minimal” simply means to indi cate that the“maximum” value is greater than the“minimal” value and vice versa.

Preferably, the clamping device 195 is associated with the curved band 140, e.g. on the outer surface of the lateral strip 155, and its dimensions in the axial direction (or in a parallel direction to the central axis X) are preferably such as not to project below said lateral strip 155, i.e. below the annular flange 120 of the container 105, so as not to in terfere with the instruments that perform the folding of the second circumferential edge 150 (see also Fig.1 1 ).

Entering into more detail, the clamping device 195 can comprise a first fixing element 200 and a second fixing element 205.

The first fixing element 200 can be fixed to the lateral strip 155 of the curved band 140, preferably at an adjacent but external area with respect to the first end portion 160.

The second fixing element 205 can be fixed to the lateral strip 155 of the curved bar 140, preferably at the second end portion 165.

The clamping device 195 can further comprise an activation lever 210 and a connecting rod 215.

The activation lever 210 can have an end 220 articulated to one of the aforesaid fixing elements, in the example to the first fixing element 200, whereas the connecting rod 215 can have a first end 225 articulated to the other fixing element, in the example to the second fixing element 205, and a second end 230 articulated in an intermediate point of the activation lever 210.

The axes of rotation of the activation lever 210 and the connecting rod 215 may all be parallel to one another and parallel to the central axis X.

In this way, by moving the activation lever 210 in one direction (the anticlockwise one in Figure 6), the clamping device 195 is able to make the end portions 160 and 165 of the curved band 140 slide towards the opening configuration and, vice versa, by moving the lever in the opposite direction, the clamping device 195 is able to make the end portions 160 and 165 of the curved band 140 slide towards the closing configuration.

Preferably, the clamping device 195 is configured so that, once the closing configuration has been reached, the end portions 160 and 165 are locked and cannot slide mutually in the circumferential direction, unless the clamping device 195 is activated again, e.g. by rotating the activation lever 210.

The clamping device 195 is mounted onto the curved band 140 during the manufactur ing of the safety ring 100, before the latter is applied to the container 105.

During the steps of applying the safety ring 100 and folding the second circumferential edge 150, the clamping device 195 is preferably maintained in the closing configuration, in order to guarantee the locking of the lid 125 onto the container 105 according to the methods that have been previously described.

In this way, the first application of the safety ring 100 can take place quickly and can be easily automated, as it does not require intervention on the clamping device 195 but on ly requires the safety ring 100 to be inserted onto the container 105 and the second end edge 150 of the curved band 140 to be folded under the annular flange 120.

After the first application, when the container 105 is to be opened, the clamping device 195 can be activated towards the opening configuration, so as to widen the safety ring 100.

In this way, the second circumferential edge 150 of the curved band 140, although radi ally folded towards the inside, can be inserted from the annular flange 120 of the con tainer 105, allowing the removal of the safety ring 100 and therefore of the lid 125. If the container 105 is to be closed again, it is possible to reposition the lid 125 and the safety ring 100, then to activate the clamping device 195 towards the closing configura tion.

In this way, the annular flange 120 of the container 105 and the perimeter edge 130 of the lid 125 can be clamped again between the first and the second circumferential edge 145 and 150 of the safety ring 100, firmly locking the lid 125.

In conclusion, it is to be observed that the clamping device 195 previously described on ly represents an example and that, in other embodiments, the clamping device 195 could be made in many other different ways, as long as it is adapted to be operated to allow the widening and narrowing of the safety ring 100.

Obviously a person skilled in the art can make numerous modifications of a tech nical/application nature to the safety ring 100 described above and the related method of use, without departing from the scope of the invention as claimed below.

Claims

1. A safety ring (100) for closing a container (105), wherein said container (105) comprises an opening (1 10), an annular flange (120) that surrounds and protrudes radi ally from said opening (1 10) and a lid (125) capable of closing said opening (1 10) and having a perimeter edge (130) able to rest on the annular flange (120), wherein the safety ring (100) comprises:

- a curved band (140) which extends about a predetermined central axis (X) and which exhibits a first and a second end portion (160, 165) overlapped on each other,

- a clamping device (195) operable to make said end portions (160, 165) slide in a circumferential direction, keeping them in mutual overlap, between an opening configuration, wherein the overlapping of said end portions (160, 165) is minimal and the diameter of the curved band (140) relative to the central axis (X) is max imum, and a closing configuration, wherein the overlap of said end portions (160, 165) is maximum and the diameter of the curved band (140) is minimal, and wherein said curved band (140) exhibits a lateral strip (155), substantially cylindrical in shape, able to surround the annular flange (120) of the container (105), a first circum ferential edge (145) projecting radially inward with respect to the lateral strip (155), which circumferential edge is adapted to be overlapped on the perimeter edge (130) of the lid (125), and a second circumferential edge (150) able to be folded under the annu lar flange (120) of the container (105).

2. A safety ring (100) according to claim 1 , wherein the first circumferential edge (145) of the curved band (140) is folded into a curl and exhibits a cross section, afforded relative to a section plane containing the central axis (X) of the curved band (140), of a substantially circular or arc shape.

3. A safety ring (100) according to claim 2, wherein the first circumferential edge (145) may exhibit a first portion (170) which extends at the first end portion (160) of the curved band (140) and a second portion (175) which extends at the second end portion (165) of the curved band (140), wherein said first portion (170) of the first circumferential edge (145) is slidably inserted in the second portion (175).

4. A safety ring (100) according to any preceding claim, wherein the first end portion

5. A container (105) comprising an opening (1 10), an annular flange (120) which sur rounds and protrudes radially from said opening (1 10), a lid (125) capable of closing said opening (1 10) and having a perimeter edge (130) adapted to rest on the annular flange (120), and a safety ring (100), wherein said safety ring (100) comprises:

- a curved band (140) which extends about a predetermined central axis (X) and which exhibits a first and a second end portion (160, 165) overlapped on each other, and

- a clamping device (195) operable to make said end portions (160, 165) slide in a circumferential direction, keeping them in mutual overlap, between an opening configuration, wherein the overlapping of said end portions (160, 165) is minimal and the diameter of the curved band (140) relative to the central axis (X) is max imum, and a closing configuration, wherein the overlapping of said end portions (160, 165) is maximum and the diameter of the curved band (140) is minimal, and

wherein said curved band (140) exhibits a lateral strip (155), substantially cylindrical in shape, able to surround the annular flange (120) of the container (105), a first circum ferential edge (145) projecting radially inward with respect to the lateral strip (155), which circumferential edge is adapted to be overlapped on the peripheral edge (130) of the lid (125), and a second circumferential edge (150) able to be folded under the annu lar flange (120) of the container (105).

6. A method for closing a container (105), wherein said container (105) comprises an opening (1 10), an annular flange (120) that surrounds and protrudes radially from said opening (1 10) and a lid (125) which closes said opening (1 10) and which exhibits a pe rimeter edge (130) resting on the annular flange (120), wherein said method comprises the steps of:

- preparing a safety ring (100) comprising:

a curved band (140) which extends about a predetermined central axis (X) and which exhibits a first and a second end portion (160, 165) overlapped on each other, and

a clamping device (195) operable to make said end portions (160, 165) slide in a circumferential direction, keeping them in mutual overlap, between an opening configuration, wherein the overlapping of said end portions (160, 165) is minimal and the diameter of the curved band (140) relative to the central axis (X) is maximum, and a closing configuration, wherein the overlap of said end por tions (160, 165) is maximum and the diameter of the curved band (140) is mini mal,

wherein said curved band (140) exhibits a lateral strip (155), substantially cylindrical in shape, a first circumferential edge (145) projecting radially inward with respect to the lateral strip (155) and a second circumferential edge (150),

- applying said safety ring (100) to the container so that the lateral strip (155) of the curved band (140) surrounds the annular flange (120) of the container and the first circumferential edge (145) is overlapped on the perimeter edge (130) of the lid (125), and

- folding the second circumferential edge (150) of the curved band (140) under the annular flange (120) of the container (105).

7. A method according to claim 6, wherein the step of folding the second circumfer ential edge (150) of the curved band (140) is performed while the end portions (160, 165) of the curved band (140) are in the closing configuration.

8. A method according to claim 6 or 7, wherein the step of folding the second circum ferential edge (150) of the curved band (140) is obtained by rolling or crimping.