Venting valve for airtight containers and method for making such a valve - Patents.com

Abstract

The present invention relates to a degassing valve (1) for airtight containers. The valve comprises a main body (2) having a central axis (A) and at least one opening (3) for the passage of gas and a seat (5) at least partially superimposed on the opening (3), a covering element (6) inserted into the seat (5) of the main body (2) to open and / or close the opening (3), and a viscous layer (9) arranged between the main body (2) and the covering element (6) and surrounding the opening (3). The valve is characterized in that it comprises a number of holding elements (10) realized integrally with the main body (2) and at least partially superimposed on the covering element (6) to surround the covering element (6) and hold it in close proximity to the main body (2).

Description

[Technical field]

[0001] The present invention relates to a degassing valve for an airtight container and to a method for realization as set out in the preambles of claims 1 and 12, respectively.

[0002] In particular, the degassing valve is one-way and the airtight container is suitable for containing products that release gas during their storage, i.e. products that tend to emit gas during storage, such as for example aromatic or odorous products, powdered products such as coffee, detergents, fertilizers, but also liquid products or fresh pasta, etc. [Background technology]

[0003] Deaeration valves of the type previously specified for containers intended to contain the above-mentioned products are known in the state of the art, for example in U.S. Pat. No. 3,595,467, EP 0 659 657 and EP 1 213 228.

[0004] The contents of the patent publication WO 2011 / 091924, issued in Europe under EP 2 528 842 on behalf of the same applicant, are also known.

[0005] In particular, WO '924 discloses a degassing valve for a container suitable for containing a gas-generating product, said container comprising a valve body and a one-way closure element movable between a closed configuration which prevents the flow of gas and an open configuration which instead allows the passage of gas.

[0006] In particular, both the valve body and the closure element are at least partially realized from biodegradable materials.

[0007] The valve-based products described in WO '924 have enjoyed great commercial success due in part to their reduced environmental impact.

[0008] Starting from these grounds, the Applicant felt the need to improve this aspect further. Summary of the Invention [Problem to be solved by the invention]

[0009] Indeed, increasingly stringent regulations and customer demands call for the creation of increasingly eco-sustainable deaeration valves that use minimal resources and are equally effective compared to deaeration valves known from the state of the art.

[0010] However, the design of such a vent valve has many technical and manufacturing complexities that are not easily resolved. [Means for solving the problem]

[0011] In this context, the technical problem underlying the present invention is to propose a degassing valve for airtight containers which overcomes the above-mentioned drawbacks of the prior art.

[0012] In particular, it is an object of the present invention to provide a venting valve for airtight containers which has a significantly reduced impact on the environment.

[0013] The described technical problem and the specified object are substantially achieved by a degassing valve for an airtight container having the technical features set out in one or more of the appended claims.

[0014] In particular, a first embodiment of the invention relates to a degassing valve for an airtight container. The valve comprises a main body having a central axis and at least one opening for the passage of gas. The main body also has a seat at least partially superimposed over the opening.

[0015] A cover element is inserted into the seat of the main body to open and / or close the opening.

[0016] A viscous layer is disposed between the main body and the cover element and surrounds the opening.

[0017] The valve further comprises a plurality of retaining elements fabricated from a single piece with the main body, the retaining elements at least partially overlapping the cover element to surround and hold it in close proximity to the main body.

[0018] A second embodiment of the invention relates to a method for realizing a valve according to the first embodiment, the method comprising the steps of providing a main body having a central axis and at least one opening for the passage of gas.

[0019] The method further includes applying a viscous layer over the main body around the opening.

[0020] The covering element is applied onto the tacky layer.

[0021] A covering element is locked onto the main body to allow opening and closing of the opening.

[0022] The main body comprises a plurality of protrusions, the step of applying the covering element comprises the sub-step of positioning the covering element between the protrusions, and the step of locking the covering element comprises the sub-step of localized plastic deformation of the protrusions to close them onto the covering element such that each protrusion defines a respective retaining element of the valve.

[0023] Advantages of the Invention The present invention solves a technical problem in that the degassing valve uses less material than known valves, due to the absence of a so-called lid. This makes it possible to obtain material savings in the manufacturing process and relative savings in the purchase of material, which are equal to about 30% compared to conventional valves. Assuming a production of, for example, 1 billion valves per year, a saving of several hundred tons of plastic material can be expected.

[0024] The use of less plastic material also ensures a reduced impact of the disposal process than prior art valves.

[0025] Furthermore, according to one aspect of the invention, it is possible to select materials to achieve a valve that is recognized as recyclable or compostable / biodegradable and therefore meets the regulations in force.

[0026] Thus, thanks to the present invention, in addition to obtaining a valve that uses less material than known valves, a valve is also obtained that meets current regulations and / or guidelines to be recognized as recyclable or compostable / biodegradable, thereby achieving the advantage that it can be recycled, i.e. the valve itself can be turned into compost, thus further reducing the impact upon disposal.

[0027] Further characteristics and advantages of the present invention will become more apparent from the illustrative, and therefore non-limiting, description of preferred but non-exclusive embodiments of a degassing valve for an airtight container as shown in the accompanying drawings. [Brief description of the drawings]

[0028] [Figure 1] 1 is a front cross-sectional view of one half of a degassing valve for an airtight container according to one embodiment of the present invention; [Diagram 2] 2 is a cross-sectional side view of components of the valve of FIG. 1 at an intermediate step in a method for making the valve of FIG. 1. [Diagram 3] 3 is a combination of a front view and a side view, both in cross section, of the component of FIG. 2 during a subsequent step in a method for making the valve of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] In the remainder of this specification, the term "biodegradable" refers to a set of irreversible chemical reactions that result in the decomposition of a particular substance, whether in natural or under artificial conditions. The level of biodegradation to be achieved for inclusion in the certification of a biodegradable material is equal to a level that is at least 90% biodegradable within 6 months.

[0030] The term "compostable" refers to a spontaneous process that occurs under certain temperature and humidity conditions (in so-called composters) that at the end transforms waste into a substance called compost. Waste that is declared compostable as specified in the standard EN13432 must meet all the following criteria: a) at least 90% biodegradable within 6 months, b) disintegrable, i.e. fragmented and invisible in the final compost (the mass of residues of the test material with a size of more than 2 mm must be less than 10% of the initial mass), c) low levels of heavy metals and no adverse effects on the compost quality, d) stability of pH value, salt content, volatile solids N, P, Mg, K.

[0031] The term "recyclable" means a material that can be used again in the manufacturing process. More specifically, "recyclable material" means a material or mixture of materials that is compatible in both mechanical and chemical recycling processes. Even more specifically, in the context of the present invention, the reference guidelines that this specification applies for the definition of recyclable materials used in degassing valves for airtight containers are publicly available on the website https: / / ceflex.eu / and are incorporated herein in their entirety.

[0032] With reference to the accompanying drawings, there is shown at 1 a degassing valve for an airtight container according to the present invention.

[0033] In particular, the valve 1 comprises a main body 2 having a central axis "A".

[0034] In particular, the main body 2 has an axially symmetric shape, although preferably not necessarily circular in plan.

[0035] The main body 2 is further provided with at least one opening 3 which, in use, selectively allows the passage of gas therethrough.

[0036] In the embodiment shown, the main body 2 comprises in particular four openings 3 each defined by a respective hole 20 (two openings 3 are visible in cross section in the accompanying figure).

[0037] In other embodiments not shown, the number and shape of the openings 3 can be varied according to operational needs.

[0038] Therefore, in the context of this specification, reference is made to a single opening 3, without loss of generality, as the same technical teachings can also be applied to solutions having two or more openings 3.

[0039] With particular reference to Figure 2, the main body 2 has an inner side 2a and an outer side 2b.

[0040] In use, the inner part 2a is placed in a container (not shown) to which the valve 1 is to be applied.

[0041] The outer side 2b faces the inner side 2a, i.e. in use it is located on the outside of the container.

[0042] More specifically, main body 2 includes a preferably planar base 4 that extends substantially perpendicular to central axis "A."

[0043] On the outside 2b, in the base 4 a central area 4a is identified, above which the opening 3 is obtained.

[0044] The central region 4a is surrounded by an intermediate region 4b which is raised in particular relative to the central region 4a.

[0045] On the inside 2a, the base 4 has a recess 4c.

[0046] An internal filter 4e is disposed within the recess 4c to prevent product disposed within the container from accumulating in the openings 3 and blocking them, in use.

[0047] Transversely to the base 4 , the main body 2 includes a side wall 7 .

[0048] Such a side wall 7 is preferably axially symmetrical, even more preferably cylindrical or conical.

[0049] The main body 2 further comprises a flange 8 connected to the side wall 7 and facing the base 4 .

[0050] The flange 8 has the function of making it possible to fix the valve 1 to the container in question.

[0051] For example, as shown in FIG. 2, the side wall 7 may have a frusto-conical shape that narrows from the flange 8 to the base 4 .

[0052] It should be noted that the main body 2 is provided with a seat 5 which is at least partially superimposed over the opening 3 .

[0053] In particular, the seat 5 can be discerned on the outer side 2b of the main body 2 in a central region 4a and in an intermediate region 4b.

[0054] The covering element 6 is inserted in the seat 5 and has the function of opening and / or closing the opening 3. In other words, the covering element 6 is a mobile element which opens or closes the opening 3 depending on the level of overpressure that arises in the container after release of gas generated by the product stored therein itself. It should be noted that thanks to the covering element 6 only the escape of gas is allowed when a certain opening threshold level is exceeded, but no ingress of fluid from the external environment into the container is allowed, i.e. the valve 1 is realised as a one-way degassing valve.

[0055] More specifically, the covering element 6 has a flat, preferably disc-shaped shape.

[0056] The covering element 6 has an inner surface facing the opening 3 and an outer surface opposite the inner surface.

[0057] The valve 1 further comprises a viscous layer 9 applied between the main body 2 and the covering element 6 .

[0058] The viscous layer 9 surrounds the opening 3 and is particularly disposed in the intermediate region 4 b of the base 4 .

[0059] In use, the viscous layer ensures adhesion of the covering element 6 to the main body 2 and the tightness of the valve 1 .

[0060] It should be noted that the covering element 6 is switchable between a closed configuration and an open configuration.

[0061] In the closed configuration, the cover element 6 adheres completely to the viscous layer 9 and closes the opening 3 gas-tightly.

[0062] In contrast, in the open configuration, the covering element 6 is at least partially separated from the viscous layer 9 .

[0063] In particular, when the gas within the container develops sufficient pressure to overcome the surface tension of the viscous layer 9, the covering element 6 switches from the closed configuration to the open configuration, allowing the gas to escape.

[0064] According to the invention, the valve 1 comprises a number of retaining elements 10 .

[0065] Said holding element 10 is realised integrally with the main body 2 and surrounds the covering element 6 and is at least partially superimposed thereon in order to hold it in close proximity to the main body 2 .

[0066] It is possible to realise the valve 1 without a lid thanks to the fact that a number of holding elements 10 surround the cover element 6 and are superimposed on top of it to hold it close to the main body 2.

[0067] It should be recalled that in fact the lid in conventional valves, whether made of conventional or compostable / biodegradable materials, acts as an element capable of holding the covering element 6 during the movement of said valve. Indeed, in such valves of the prior art, it is assumed that the lid acts as a stop for the covering element 6 itself, in order to prevent it from moving from its position and / or even being able to leak.

[0068] In contrast, in the valve according to the present invention, a lid is no longer necessary, since the holding elements 10 are arranged to overlap each other at least partially, preferably over their entire extension, in order to hold the cover element 6 close to the main body 2.

[0069] More specifically, the retaining element 10 faces the outer surface of the covering element 6 .

[0070] In the open configuration, the closure element 6 abuts against at least one of the holding elements 10 depending on the conditions of use, or in any case can even be partially separated from the viscous layer 9, in order to allow the escape of gas produced by the substance contained in the container, but at the same time cannot leak out towards the main body 2.

[0071] More particularly, it should be noted that the retaining elements 10 are each defined by a respective projection 11 obtained on the main body 2 and arranged on the outside of the seat 5 .

[0072] In particular, the seat 5 is defined by a projection 11 , which maintains the closure element 6 in a central position in the opening 3 .

[0073] More specifically, the projections 11 arise away from the base 4 of the central body 2, particularly on the outer side 2b.

[0074] It should be noted that each projection 11 is curved towards the seat 5 .

[0075] In other words, the projection 11 arises along a surface that is curved downwards, i.e. towards the seat 5 .

[0076] In one embodiment (not shown), the projections 11 occur along a circumferential arc about the central axis "A" along the outer region 4d of the base 4 that surrounds the intermediate region 4b.

[0077] In particular, each protrusion 11 is an upper surface 11c curved towards the seat 5; The underside 11d is curved towards the seat 5 The following is defined: The lower surface 11d is joined to the upper surface 11c by a curved portion 11e.

[0078] According to a particular aspect, the projection 11 distinguishes a first head end 11a and a second head end 11b. It can be seen that the first head end 11a is integrated with the base 4, whereas the second head end 11b is free.

[0079] According to the embodiment shown in the accompanying drawings, each projection 11 arises away from the base 4 of the body along a circumferential arc about the central axis A such that the second end 11b is closer or closer to the central axis A than the first end 11a.

[0080] Thanks to this configuration of the projections 11 it is possible to maintain the closure element 6 in a central position in the opening 3 .

[0081] According to one embodiment, the valve 1 comprises at least two protrusions 11 .

[0082] In the embodiment shown in the accompanying figures, the number of protrusions 11 is four, however, in other non-illustrated embodiments of the present invention, the number of protrusions 11 may be three or any number such as five, six, seven, eight, etc.

[0083] Note that the protrusions 11 are evenly angularly spaced relative to the central axis "A."

[0084] Also, each protrusion 11 is angularly separated from adjacent protrusions 11 by a respective spacing 12 .

[0085] It should also be noted that each retaining element 10 is produced by plastically deforming a respective projection 11 .

[0086] According to one embodiment, the degassing valve 1 is made from recyclable materials.

[0087] More particularly, the degassing valve 1 is at least 90% made of a single recyclable material, ie is realized using at least 90% of a single recyclable material.

[0088] In other words, the main body 2 of the valve 1, the retaining element 10 and the covering element 6 may all be made of at least 90% of the same material, for example the material may be selected from PET, polyethylene, polypropylene and recyclable polymers.

[0089] According to one embodiment, the degassing valve 1 is made of recyclable materials obtained from a mixture of two or more recyclable materials, i.e. a mixture compatible with a recycling process.

[0090] In other words, the main body 2, the retaining element 10 and the covering element 6 of the valve 1 may be made of a mixture of two or more of materials, such as for example PET, polyethylene, polypropylene and recyclable polymers.

[0091] Such recyclable materials or mixtures thereof are suitable for recycling by chemical or mechanical recycling.

[0092] According to an alternative embodiment to that described above in the selection of materials for realizing the valve, the degassing valve 1 is made of compostable / biodegradable materials, i.e. materials selected to meet the specifications classified in standard EN13432 or the equivalent standard ISO14855-1:2005 or the equivalent standard ASTM D6400-04, in particular with regard to standard EN13432, which is a harmonized standard and reported in the Official Journal of the European Union providing a presumption of conformity with the European Directive 94 / 62EC on packaging and packaging waste.

[0093] According to one embodiment, the viscous layer 9 is realized as a biodegradable oil, such as vegetable oil.

[0094] The method for making the valve 1 described above is also part of the present invention.

[0095] According to this method, the main body 2 and the covering element 6 are realised by known processes, for example moulding.

[0096] A viscous layer 9 is applied onto the main body 2, particularly within the intermediate region 4b.

[0097] Thereafter, the cover element 6 is positioned on top of the viscous layer 9 , in particular between the projections 11 .

[0098] The cover element 6 is then locked to the main body 2 so as to allow the opening 3 to be opened and closed.

[0099] In particular, the projections 11 are locally plastically deformed to close them on the covering element 6 so that each projection 11 defines a respective retaining element 10 .

[0100] The local plastic deformation of the protrusion 11 is performed by ultrasonic waves.

[0101] In particular, the sonotrode 100 is placed over the protrusion 11 and then activated to transfer energy to the protrusion 11 .

[0102] It should be noted that the sonotrode 100 has a contact surface 100a in the shape of a circular crown.

[0103] Obviously, those skilled in the art may make numerous modifications and variations to the above-described configurations in order to meet their fortuitous and specific needs, all of which nevertheless fall within the scope of protection defined by the following claims.

Claims

1. a main body (2) having a central axis (A) and having at least one opening (3) for the passage of gas and a seat (5) at least partially superimposed on said opening (3); a covering element (6) inserted into said seat (5) of said main body (2) to open and / or close said opening (3); a viscous layer (9) disposed between said main body (2) and said covering element (6) and surrounding said opening (3); a plurality of holding elements (10) made from a single piece together with said main body (2) and at least partially superimposed on said covering element (6) to surround said covering element (6) and hold it in proximity to said main body (2); Equipped with The main body (2) comprises a base (4) extending perpendicular to the central axis (A''), and laterally to the base (4), the main body (2) comprises side walls (7); The retaining elements (10) are defined by respective projections (11) each projecting radially from the side wall (7), each projection (11) is curved towards said seat (5) and defines a lower surface (11d) which is curved towards said seat (5), Degassing valve (1) for airtight container.

2. 2. A vent valve (1) according to claim 1, wherein each projection (11) defines an upper surface (11c) that is curved towards the seat (5).

3. 2. The vent valve (1) according to claim 1, wherein the lower surface (11d) is joined to the upper surface (11c) by a curved portion (11e).

4. 2. A degassing valve (1) according to claim 1, wherein each protrusion distinguishes between a first end (11a) and a second end (11b), the first end (11a) being made from one piece with the side wall (7) and the second end (11b) free, and the second end (11b) being closer to the central axis (A) than the first end (11a).

5. 2. The degassing valve (1) according to claim 1, wherein the covering element (6) is switchable between a closed configuration in which it completely adheres to the viscous layer (9) and hermetically closes the opening (3), and an open configuration in which it is at least partially separated from the viscous layer (9).

6. 2. A vent valve (1) according to claim 1, wherein each projection (11) is angularly separated from its adjacent projection by a respective spacing (12).

7. The vent valve (1) according to claim 1, wherein the number of said projections (11) is at least two, three, four or more.

8. 2. The vent valve (1) according to claim 1, wherein the vent valve (1) is realized to at least 90% by a single recyclable material.

9. 2. The vent valve (1) according to claim 1, wherein said vent valve (1) is made of recyclable materials obtained from a mixture of two or more recyclable materials.

10. 9. The vent valve (1) according to claim 8, wherein the recyclable material or the mixture of recyclable materials is selected from PET, polyethylene, polypropylene and recyclable polymers.

11. 2. The deaeration valve (1) according to claim 1, wherein the deaeration valve (1) is made of compostable / biodegradable materials according to standard EN 13432.

12. - providing a main body (2) having a central axis (A) and having at least one opening (3) for the passage of gas; - applying a sticky layer (9) onto said main body (2) around said opening (3); - applying a covering element (6) onto said adhesive layer (9); - locking said covering element (6) onto said main body (2) to allow opening and closing of said opening (3); - realizing a plurality of holding elements (10) integral with said main body (2) so as to be at least partially superimposed on said covering element (6) in order to surround said covering element (6) and hold it in proximity to said main body (2); - realizing said main body (2), said covering element (6) and said plurality of holding elements (10) in the same material or in a compatible material in said recycling process; Including, characterised in that the step of realising the retaining elements (10) comprises a step of plastically deforming the retaining elements (10) to define a plurality of protrusions (11) arising away from the base (4) of the central body (2) and closing them on the covering elements (6) in such a way that each protrusion (11) defines a respective retaining element (10) of the valve (1). A method for making a one-way vent valve (1) according to claim 1.

13. The method of claim 12 , wherein the plastic deformation substep is achieved by ultrasound.

14. Each protrusion is - positioning a sonotrode (100) at one end (11b) of each of said projections (11); activating the sonotrode (100) 14. The method of claim 13, further comprising a further substep.

15. 10. An airtight container adapted to contain products that release gas during their storage, said container comprising a vent valve, said vent valve being as claimed in claim 1.

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