Technical Field of the Invention

Invention herewith described, generally, refers to closures, i.e. elements which have parts for gripping the external periphery of the neck or wall which defines an opening for pouring or emptying, and more precisely to single use closures which are opened by punching one part of the closure.

According to the International Patent Classification, this invention is sorted, i.e. classified and marked with classification symbols: B65D 51/20.

Technical Problem

Technical problem being solved by herewith explained invention, consists of the following: how to constructionally solve a single use closure which would provide complete tightness of the container, with vertical outer walls without threads, to be sealed by the closure, which would provide an easy and safe use without risk of injury to the user, and for whose removal from the container no additional tools are required, while, at the same time, it has an attractive artistic design and a reasonable price.

State-of-Art

Generally, known are different constructions of closures for enclosing fluid and solid materials, from metal crown caps to closures applied onto beer and other beverage cans or on some types of milk packages.

The shortcoming of the simplest closures is that these do not provide complete tightness, while more modern solutions are more expensive whereby for opening the container at least two steps are required, and there is a possibility that the user may hurt her/his fingers.

Searching the patent documentation and reviewing professional works in this field, and the knowledge on market promoting, no similar solution of the set out technical problem has been found. Brief Description of the Invention

Invention in the subject is used for tight seal closing of various containers of different capacity and without threads, with achieving the underpressure in the container at the moment of placing the closure thereon. The closure according to the invention consists of a shaped metallic cylindrical cover with a cambered bottom, a specially shaped elastic metal bellow with a vertical funnel-like recess and a rubber gasket. The cover and the bellow are shaped in a process of mechanical extrusion in a previously prepared mould. The bellow is then glued to the cover above the cambered bottom, so that chamber is created between the cover and the bellow. This chamber is then filled with pressurized gas. The pressure in this chamber causes a partial, slight deformation (increase) of diameter of the closure, which provides proper resting onto the walls of the container and its closing. The top edge of the rim of the container is slightly rounded and cambered towards the inside; herewith the quality of the seal (tightness) is additionally improved. Rubber gasket is applied from the inner side of the closure and rests onto the inner side of the container which is being closed.

Finished closure is placed on the container, which is automatically closed on a special machine, in such way that underpressure is achieved below the closure. This ensures that closure remains on the container permanently and provides a complete tightness all up to the loss of the vacuum.

Opening is achieved when pressure is exerted onto the upper surface of the bellow, thus punching the cambered bottom of the cover, with bottom part of the funnel-like recess, positioned on the bellow. Punching is carried out on a certain weak spot, i.e. along the line of reduced resistance accomplished on the bottom. In such a way, the gas from the chamber enters into the container, the pressure in the container and the chamber of the closure are made equal, causing the reduction of the diameter of the closure itself, thus its easy removal from the container is enabled. A characteristic sound accompanies this operation of punching the cambered bottom.

The advantage of herewith described solution, compared to the known state-of-art, is in the complete tightness of the container, easy and safe opening, low price and artistic design, whereby the container is punched in a unique and engaging way and a specific sound effect accompanies the opening, No additional tools are required for opening; therewith this one is different from crown and similar single-use closures, the opening of which requires an opener.

The closure according to the invention is sanitarily very efficient, thus outlining the difference from, e.g. a can, where, during the opening, the metal part, which is in contact with the environment, is punched (pushed towards inner side), hence the liquid which is being consumed comes into contact with part pushed inside, which can be dusty, dirty, etc., therefore it is necessary to wash hands prior to opening the can and handkerchief cleaning of the surface of the closure is inevitable, as research proved the existence of health harmful bacterial colonies.

It should be emphasized that due to the above described reasons (closure upon opening becomes functionally and technically useless), the closure can be more in use with products intended for instant consumption, i.e. have to be used immediately upon opening, either due to the characteristics of the product itself (e.g. highly perishable upon opening) or due to the wish of the producer to influence the speed/frequency of consumption of the product in this way. Moreover, as the closure can't be reused for closing the bottle/container from which it is removed, nor for closing any other bottle/container, better protection of the original product from illegal counterfeiting (fakes) is provided, compared to the so far known solutions.

The closure according to the invention will be described in detail further on, with reference to the figures of the drawings attached.

Short Description of the Figures of the Drawings

Invention is described in detail in the example of embodiment shown in the figures of the drawings, in a large-scale view, where:

Figure 1- represents side view of the closure with quarter cross-section,

• Figure 2- represents a closure in top view,

Figure 3 - represents detail A from Figure 1,

Figure 4 - represents vertical cross-section of the closure,

Figure 5 - represents detail A-A in Figure 4,

Figure 6 - represents large-scaled detail B in Figure 5,

• Figure 7 - represents detail C in figure 4, and at the same time, cross-section D-D in Figure 6,

Figure 8- represents partial cross-section of the closure fitted on the container,

Figure 9- represents the closure, in bottom view in an isonometric representation, and

Figure 10- represents the closure, in bottom view in an isonometric representation.

Detailed Description of the Invention

The closure, according to the invention, consists of: a metal cylindrical cover 1, a bellow 2, and a rubber gasket 3. Along the rim of the cylindrical cover 1 are accomplished vertical stiffenings 10, and on the top side is accomplished/cast a cambered bottom 9. On the top side of the cover 1, and above the cambered bottom 9 is set a metal bellow 2 which is glued along its rim 15 on an annular spot 14, therewith forming a tight sealed chamber 5. From the inside of the cover 1, a rubber gasket 3 is applied. The below 2 is achieved in the form of an accordion bellow, with vertical funnel-like recess 6, whose shape provides solidity necessary for punching the cambered bottom 9. The chamber 5 is filled with gas of certain overpressure (dimensions of the closure determine the value of the overpressure in bars (a unit of pressure)) during the process of gluing of the metal bellow 2 onto the top side of the cover 1. Overpressure in chamber 5 causes a partial slight deformation (i.e. increase) of the diameter of the closure, thus providing proper resting of the closure described as the invention, onto the walls of the container 12 and its tight closing. For the safety, the top edge 11 of the container 12 is slightly rounded and at the same time cambered towards the inside 13 of the container 12, thus improving the quality of the closing (achieving the tightness). Rubber gasket 3 is applied on the inner side of the closure 1, below which underpressure is achieved at the time of closing of the container 12 in order to keep the closure on the container 12 permanently, and to provide complete tightness all up to the moment of vacuum loss. The loss of vacuum is achieved during use, when the pressure is exerted onto the top surface of the bellow 2, whose round bottom 7 punches the centrally positioned circular segment 8 of the cambered bottom 9 of the closure. Punching happens at determined impressed weak spot accomplished by reducing the thickness of the bottom 9, i.e. along the line 4 of reduced resistance accomplished on the bottom 9. Therewith gas from chamber 5 is released. Gas from chamber 5 enters into the container 12, and increases the pressure compared to the pressure of the environment, enabling the easier removal of the closure. Circular segment 8, formed by punching the bottom 9, does not fall into the container 12, because it is not weakened along the peripheral length of 2-3 mm, i.e. the line 4 of reduced resistance, being accomplished on the bottom 9, does not represent a complete circle, hence upon punching, the circular segment 8, remains hanging towards the inside 13 of the container 12.

Manufacturing process of the closure according to the invention is following: manufacturing of the cover 1 and the bellow 2 is done by extrusion from a metal strip in a previously prepared mould. Depending on the desired application, the closure can be produced from aluminum alloy, steel, brass or some other metal. On the inner side of the cover 1, which enters into the container 12, on the annular edge 16, rubber gasket 3 is applied. Rubber gasket 3 can be made of a foodstuff rubber or plastic material causing no harm to the health. While gluing metal parts of the closure, chamber 5 is formed and at the same time pressurized gas is inserted in that chamber. Inserted gas with overpressure stretches the closure (enlarges it), so that its dimension is larger than the opening of the neck of the container 12, which is being closed. Due to the elasticity of the layer of the rubber gasket 3 on the closure, this enlargement is compensated. When manufacturing bellow 2, its bottom part, i.e. round bottom 7, is shaped so that it can punch a certain spot along the line 4 of reduced resistance on the top part of the bottom 9, so that the gas from the chamber 5 is released and enters into the container 12, equalizing the pressure in the container 12 and chamber 5 and causing the reduction of the diameter of the closure itself; thus enabling its removal. Galvanic protection and lithography can be used for the finishing.

The closure requires no special shaping and manufacturing of the sealing surfaces, except that they are flat and smooth.

The way of using the closure, according to the invention, is following: onto the previously filled container 12, on a special machine, in the chamber wherein vacuum is created, by using a special tool, the closure is positioned by exerting constant pressure along the annular rim 16 of the closure. Having the rubber gasket 3 on the closure passed over the edge 11 of the container 12, the closure is permanently set onto the container 12. For removing the closure from the container 12, it is necessary to press top side of the bellow 2, and therewith the bottom wall of the chamber 5, i.e. cambered bottom 9, along the line 4 of reduced resistance will be punched and the gas from chamber 5 of the closure will be released. Upon releasing the gas, dimensions of the chamber 5 in the closure will be reduced, thus easier removal of the closure will be enabled. The released gas from the chamber 5 enters into the empty space in the inside 13 of the container 12 which was closed, increasing the pressure in respect to the environment and therefore enabling easier removal of the closure and emptying the content from the container 12. This condition means that containers 12 are not filled to the top, but that there has to be some empty space which should be at least 10 % of the total capacity of the container.

Invention in the subject is not restricted only to the above described example of embodiment. Thus, for example, its use is possible not only in the field of food industry, but also in other fields, such as pharmacy, oil and lubricant industry, etc. Moreover, it is possible to realize numerous variants of closures according to the invention, for example, instead of metal, some constructional elements can be accomplished in plastics or some other suitable material, or instead of gluing appropriate constructional elements some other technique of attaching can be used, whereby these variants do not exceed the scopes of protection defined in the patent claims in the continuation.