DESCRIPTION

SUMMARY OF THE INVENTION

The present invention relates to a device and a method for carrying out tapping from containers for storing more or less dense fluids with or without the presence of gas, and finds application both in the foodstuff sector and in the cosmetics and pharmaceuticals sectors. In particular, in the foodstuff sector, the invention may regard all those liquids or beverages that, for example, contain carbon dioxide due to fermentation in the production process or added artificially or both, but also non- effervescent or still beverages, hence without the presence of gas.

A peculiar characteristic of the present invention is that, unlike the majority of the devices already existing in the foodstuff sector, it does not make use of additional carbon dioxide or other gas (such as nitrogen) in order to obtain the propulsive effect of tapping of the liquid from the storage container into a possible container for final use.

Taking the specific case of beer, with the present invention a method of tapping is obtained that maintains intact the genuineness of the beverage, without falsifying its natural composition via contact of additional carbon dioxide or other thrust gases. This may apply also to all other effervescent beverages, whether alcoholic or non-alcoholic, such as beverages like colas, orangeade, sparkling wines, prosecco, etc., where the effect of tapping from the storage container is obtained thanks to the use of additional carbon dioxide that functions as agent of propulsion and thrust for exit of the beverage.

The ensuing description will make reference by way of example to this specific use, it being understood that the device and the method forming the subject of the present invention may find application also for tapping of dense and semi-dense liquids and regard not only the beverage sector but also the cosmetics and pharmaceuticals sectors.

FIELD OF APPLICATION AND STATE OF THE ART

Once beer was served directly from barrels via a tap, merely by gravity. When a machine was invented provided with cylindrical piston pump with valves that prevented reflux, carbon dioxide was introduced into the barrels to prevent oxidation of the beer and facilitate draught of the pump. With the passage of time, the use of manual pumps has been abandoned, and today carbon dioxide is used at a pressure sufficient to push the beer up to the delivery tap.

The carbon-dioxide content of beer (referred to as "degree of saturation") cannot, however, overcome certain limits, which depend upon the brand and upon the type of the product: in given situations, as in systems located in cellars (where the distance from the keg to the tap horizontally and vertically comes to play a significant role) , its amount might not be sufficient to pump the beer up to the tap from which it is drawn, but the pressure cannot be increased too much since, otherwise, an excessively effervescent beer would be obtained up to the point that only froth comes out of the tap. This problem was tackled in the last century by Guinness who used a mixture of carbon dioxide and nitrogen, where the part of carbon dioxide contained in the mixture maintains effervescence of the beer and nitrogen serves for the thrust.

However, systems that use carbon dioxide and nitrogen for draughting beer on tap present numerous drawbacks: it is necessary to acquire and transport the cylinders of both of the pressurized gases; there is a marked environmental impact owing to introduction of the two gases into the air; the organoleptic characteristics of the beverage are in any case altered; and there are different qualities of mixing according to the supplier.

To attempt to eliminate the introduction into the beer of carbon dioxide used as thrust gas, Carlsberg has recently patented and introduced an innovative method of tapping known as "Draughtmaster" , which eliminates recourse to carbon dioxide and replaces the traditional returnable kegs, with collapsible kegs made of PET (recyclable material) . However, the tapping device for this solution is rather complex to use and calls for a skilled operator to guarantee proper operation .

The task of the present invention is to provide a tapping method and a tapping device that do not require introduction of carbon dioxide and/or other gas into the beverage to be tapped so as to keep the original organoleptic characteristics of the beverage intact, that do not require particular collapsible kegs for transport and draughting of the beverage, and that at the same time is simple, inexpensive, reliable, and can be easily employed also in versions for purely domestic use .

The above purpose has been achieved by providing a tapping device basically constituted by a container made of rigid material, which is preferably cigar- shaped or cylinder-shaped with a hemispherical head, and with a volume equal to the volume that is deemed necessary for use and storage of the liquids. This container contains within it two distinct chambers, both equipped with opening/closing means for communication with the outside, said chambers being separated completely by a diaphragm of variable geometry and having volumes that are variable in a way inversely proportional to one another.

One of the chambers is designed to contain the beverage to be tapped, whereas the other is a thrust chamber where there is always present a pressure that is in any case higher than or equal to the pressure that enables exit of the beverage from the first chamber, supplying not only the thrust necessary to overcome the losses of head downstream of the outlet for the beverage from the first chamber, but also a rate of exit of the liquid that will afford the required flow rate and the desired exit times.

In a first embodiment, the pressure in the thrust chamber is ensured by introduction of a propellant fluid - possibly even air - which is brought under pressure via a compressor set upstream of the tapping device .

In a second embodiment, it is envisaged that the thrust chamber is already filled with pressurized gas when the containment chamber is empty.

Constituting a peculiar characteristic of the invention is the fact that the separating diaphragm between the two chambers is able to undergo deformation and adapt progressively to the internal shape of the container, at the same time ensuring that there is no passage of the liquid foodstuff from the chamber in which it is contained to the one in which the pressurized fluid is contained and vice versa.

In a first embodiment, the diaphragm is constituted by elastic material and acts as an elastic membrane, but it may also be made of non-elastic material having a shape designed to mate with the walls of the container (such as a bellows or a limp bag or bladder) .

Consequently, at each tapping, the thrust chamber acquires a volume equal to the volume of the liquid foodstuff tapped, said volume being completely filled by the pressurized fluid that is introduced or by expansion of the pressurized fluid already present.

With a device of this sort, it will hence be possible to carry out tapping of a liquid contained in the containment chamber following the operating procedures described in what follows, which are different for the two embodiments referred to above.

In the case where a propellant fluid is not present in the thrust chamber:

the containment chamber is filled with the liquid foodstuff to be dispensed; and

pressurized fluid is introduced into the thrust chamber, underneath the variable-geometry diaphragm, which will tend to swell from the bottom to the top, and simultaneously the delivery tap of the containment chamber is opened; the thrust chamber acquires a volume equal to that of the liquid foodstuff tapped, said volume being filled by pressurized fluid coming from a compressor or from a pressurized cylinder.

In the second case, when pressurized fluid is already present in the thrust chamber:

the beverage to be tapped is introduced, at a pressure higher than that of the thrust chamber, into the containment chamber; the separating diaphragm is pushed downwards as the beverage fills the containment chamber, further compressing the gas already present in the thrust chamber; it will thus be sufficient to open the delivery tap of the containment chamber for the beer to be able to come out.

With successive opening and closing of the delivery tap, the liquid foodstuff contained in the containment chamber is then tapped until the volume of this chamber becomes zero and is totally replaced by the volume acquired by the thrust chamber. This also guarantees total emptying of the containment chamber, with complete exit of the liquid foodstuff contained therein .

According to a further variant of the invention, it is envisaged that the tapping device is integrated with a pressurizecl-gas reservoir, which is connected, with interposition of a pressure reducer, to a gap in communication with the thrust chamber, delimited by the elastic membrane.

Further characteristics and advantages of the present invention will emerge clearly from the ensuing detailed description with reference to the attached drawings, which illustrate, merely by way of non- limiting example, a preferred embodiment thereof. In the plates of drawings:

Figure 1 is a schematic illustration of the device according to the invention, with the containment chamber filled with the beverage to be tapped and the thrust chamber in which a pressure ^~ P ₂ is present higher than the counterpressure that the beverage encounters at outlet from the tap S i ;

Figure 2 shows a subsequent operating step of the same device, where the containment chamber has reduced proportionally its volume, to the advantage of the volume of the thrust chamber, on account of a plurality of tapping operations carried out;

Figure 3 shows a third operating step, where the containment chamber has markedly reduced its volume, to the advantage of the thrust chamber;

Figure 4 shows in front elevation a first embodiment of the invention, which envisages a cylindrical container with hemispherical dome formed by a base and an overlying casing, where in the coupling area a variable-geometry separating diaphragm is provided;

Figures 5 and 6 show the same container in perspective view, from above and beneath, respectively;

Figure 7 is a vertical section of the container of Figure 5 that shows, on the bottom of the container, positioning of the variable-geometry diaphragm that functions both as an elastic membrane capable of undergoing deformation and adapting progressively to the internal shape of the container and as an 0-ring that is able to ensure that there is no passage of the liquid foodstuff from the chamber in which it is contained to the one in which the pressurized fluid is contained;

Figure 8 is the same vertical section as that of Figure 7, where the base and the overlying casing are detached to highlight how, in the coupling area, seats are provided for positioning the part of the diaphragm that functions as 0-ring;

Figures 9 and 10 show, in front view and in perspective view from beneath, respectively, the elastic diaphragm or membrane that functions also as CD- ring;

Figures 11a and lib show, in front elevation, a second embodiment of the invention, where the cigar- shaped container is formed by two parts coupled together, with interposition in a fluid-tight way of a variable-geometry diaphragm identical to the one that has already been illustrated, prior to coupling and after coupling, respectively;

Figures 12 and 13 show in vertical section the same container as the one illustrated in Figures 11a and lib, respectively, highlighting the 0-ring function of the elastic diaphragm; Figure 14 is a perspective view of a cigar-shaped container with a pressurized-gas reservoir integrated therein, according to a different embodiment; and

Figure 15 shows an enlarged detail of the pressurized reservoir of Figure 14.

DETAILED DESCRIPTION OF THE INVENTION

According to the present invention, the tapping device comprises a cigar-shaped or cylinder-shaped container with hemispherical head, which is preferably made of rigid materials whether metal, e.g., aluminium and stainless steel (for alimentary use if applied in the food sector) to obtain a reusable device, or plastic (e.g., PET for foodstuffs if applied in the food sector, or other types of polymers compatible once again with alimentary use) to obtain, in this case, a device that is reusable and/or disposable but made of materials that are entirely recyclable, or finally composite (such as Treta Pak or the like, for alimentary use if applied in the food sector) that is totally or partially recyclable.

With reference to Figures 1, 2, and 3, a schematic representation of the device is provided by way of example .

As highlighted in the figures listed above, the device D forming the subject of the invention comprises two chambers Ci and C2, separated by a diaphragm M of variable geometry, which guarantees total separation of the two chambers, without enabling any passage from one to the other whilst enabling variability of the volumes of the chambers Ci and C2 in an inversely proportional way . Assume that the chamber Ci is the one that receives the liquid to be tapped. This chamber is provided at the top with an outlet, with a tap or flow- interruption system U that, by opening and closing, controls dispensing of the liquid at outlet, and with another opening Si that enables, during filling of the device with the liquid foodstuff, the air initially contained in the chamber Ci to come out, guaranteeing that the chamber Ci will be filled only with the desired liquid product. Also this opening Si is equipped with a tap or flow-interruption system, which, during filling, is open for venting air, whereas, once filling has terminated, it is closed so as to ensure during use of the device that the liquid that is to be dispensed will have as sole outlet passage the outlet U.

The chamber C ₂ is a chamber that is filled with a fluid of a gaseous nature (air) or else with a fluid of a liquid nature (water) , which is set under pressure by a compression device (not illustrated) , and is introduced through a bottom opening I, which is also equipped with a tap or flow-interruption system. Also the chamber C ₂ is provided with an opening S ₂ , equipped with a tap or flow-interruption system, which enables the chamber itself and in general the container to be brought back to atmospheric pressure after the chamber Ci has been completely emptied.

Considering all the elements constituting the device, in a step zero, the chamber Ci will be filled with liquid, which may occupy even the entire volume of the container except for the space occupied by the diaphragm separating the two chambers. Instead, the chamber C ₂ will start in a condition of minimum volume that may even be close or equal to zero but with an internal pressure ^~ P ₂ > Po _? where Po is the external counterpressure downstream of the outlet tap U. As long as the tap U remains closed we have the condition P2 = Pi > Ρο· When the tap of the outlet U is opened, it enables exit of the liquid foodstuff caused by the new distribution of pressure P2 > Pi > Ρο·

By introduction of pressurized fluid through the tap, the pressure P ₂ will be kept constant and calibrated in order to exert the thrust necessary to overcome any possible losses of head downstream of the outlet U, which are generated by the pipes and by possible devices for refrigeration of the liquid foodstuff. Basically, the pressure Po is the counterpressure to be overcome because it is the sum of the atmospheric pressure P _a tm _/ - the resistance and loss of head of the pipes, and further head losses caused during possible passage of the liquid tapped into a refrigerating system and due to the elements themselves constituting the device. Furthermore, for calibration of the pressure P ₂ also the rate of exit of the liquid foodstuff from the tapping system must be taken into consideration to guarantee the flow rate required and the exit times desired for dispensing the beverage.

Once the difference of pressure has been generated upon opening of the tap U, there will thus be the reduction in volume of the chamber Ci, with consequent exit of an equal volume of liquid foodstuff, and there will simultaneously be an increase in volume of the same amount of the chamber C2, with consequent introduction of compression fluid, which is also of the same volume as that acquired by the chamber C2. This behaviour will persist until the volume of the chamber Ci has become zero and has been replaced totally by the volume acquired by the chamber C2 owing to successive opening and closing of the tap of the outlet U. This also guarantees total emptying of the chamber Ci and complete exit of the liquid foodstuff.

According to a peculiar characteristic of the invention, the effect of variation in an inversely proportional way of the volumes of the two chambers Ci and C2 is obtained thanks to the type of architecture of the diaphragm separating the chambers themselves, as illustrated in the figures described in what follows.

Figure 4 represents the solution with a diaphragm 3 made of elastomeric and/or latex-based material, with highly elastic characteristics. The diaphragm 3 functions as elastic membrane, which, under the pressure condition P ₂ > Pi > Po is able to undergo deformation and adapt progressively to the internal shape of the container 1. The diaphragm 3 is able to ensure that there is no passage of the liquid foodstuff from the chamber in which it is contained to the one in which the pressurized fluid is contained and vice versa .

Figure 4 presents a solution in which the diaphragm itself has an architecture such as to function both as 0-ring 5 and as membrane as a single element. According to this solution, the container 1 is made up of two parts 7 and 9, which in the coupling area have corresponding flanges 7a, 9a that have seats for positioning the peripheral part of the diaphragm 3 that functions as 0-ring, as may be seen in the enlarged details of Figure 7 and 8.

Starting once again from Figure 4, operation may be summarized as follows. In the starting condition, the thrust chamber 13 is empty and with a zero or almost zero volume, and the diaphragm 3 is completely stretched out and resting on the wall of the container 1 down the bottom whilst the containment chamber 11 is at the maximum of its volume and completely full of liquid (foodstuff) . The initial distribution of pressure is P2 = Pi > ^~ Po, and with the outlet 15 closed. Upon opening of the outlet 15 of the chamber 11, the new condition P2 > Pi > Po will be obtained, and in this condition the liquid (foodstuff) will tend to decrease in volume owing to exit through the outlet 15 from the chamber 11, whilst the chamber 13 will acquire a volume equal to that of the liquid (foodstuff) tapped, which will be occupied by the pressurized fluid entering from the inlet 17 downstream of the diaphragm 3. All this will occur simultaneously with elastic deformation of the diaphragm 3, which will tend to move away from the bottom of the container 1, adhering slowly to the walls towards the top outlet 15. This will occur up to the final condition of total emptying of the chamber 11 and up to the maximum expansion in volume of the chamber 13 allowed .

It should be noted that the diaphragm 3 may be made also of a non-elastic material having a shape that reproduces exactly the inside of the container. Also silicone or foamed silicone for alimentary use may be employed .

Represented in Figure 7 is a different architecture of the container 1 of a symmetrical type. Apart from the fact that the dynamics of emptying coincides with the one just described and on account of the extended position of the membrane completely adherent to the walls of the chamber 13 at the start, in the specific case the pressure P2 will have an assisting component represented by the elastic restoring force of the diaphragm 3, which will tend, according to an elastic law and with variable force, to push the liquid (foodstuff) outwards when the outlet 15 opens. This situation will persist until the diaphragm 3 returns to its natural shape at rest, thus constituting a component of variable elastic resistance to be added to the pressure Po. All this means that, during tapping of the liquid (foodstuff), according to how the diaphragm 3 is positioned, it is necessary to adapt the pressure ^~ P ₂ to the level necessary to obtain that the aforesaid head losses and the elastic restoring force of the diaphragm will be overcome.

The step of filling and charging of the container can be carried out in different ways, according to the solution that is applied. Starting from the solution of Figure 2, the diaphragm 3 may be positioned on the bottom, and filling of the chamber 11 may be obtained by gravity even from the outlet 15 itself; alternatively, the diaphragm 3 can be positioned at the outlet 15, and by a negative-pressure effect with P2 < Po it will be possible to obtain displacement of the diaphragm towards the bottom thus carrying out filling via a suction or syringe effect. In the solution of Figure 3, the liquid (foodstuff) may be introduced initially by gravity and subsequently under pressure against the elastic force until the diaphragm 3 adheres altogether to the walls of the chamber 13 and hence the chamber 11 is completely filled. Otherwise, it is possible to create a negative pressure in the chamber 13 until the diaphragm 3 adheres to the walls of the chamber 13, and subsequently the chamber 11 is filled only by gravity. Lastly, it is possible to create a pressure in chamber 13 in such a way that the diaphragm 3 adheres to the walls of the chamber 11 up to the outlet 15. Next, when the liquid (foodstuff) can start to enter, the pressure is reversed until a negative-pressure effect is obtained. In this way, the diaphragm 3 comes to adhere to the walls of the chamber 13 towards the bottom, enabling filling to be completed owing to a suction or syringe effect.

The version of the device with integrated pressurized-gas reservoir may have an architecture like the one illustrated in Figures 14 and 15.

The reservoir 21 is pressurized via the duct 22. The reservoir is in communication with the gap 23 via the duct 24, with interposition of a pressure reducer 25, where also a manometer 26 could be housed for checking the pressure. The gap 23 is connected to the volume 13 that is underneath the membrane 3 via the passage 29. The pressurized gas is regulated via the pressure reducer 25; by acting on the membrane 3, it will come into pressure equilibrium with the volume 11 that is to contain the liquid.

Assume that the pressure reducer 25 is calibrated in such a way that downstream thereof the pressure of the gas is reduced to 2 bar and the reservoir 21 contains pressurized air at 10 bar. By way of simplification, assume also that the liquid is practically incompressible and that the air being compressed follows, in a way very close to the real situation, a law of compressibility proportional to the pressure. Hence, if the reservoir 21 has a volume of 5 1 and the air inside the reservoir is brought to the pressure of 10 bar, we shall have an amount of uncompressed air of approximately 50 1. In fact, the law would be V _air = V _reservoir · P _a i _r . This would mean that, by getting the liquid product present in the volume 11 to exit via the passage provided with tap 15, the pressure in the volume 11 itself would be kept constant at 2 bar until the pressure in the reservoir 21 reaches precisely 2 bar. When the reservoir 21 has reached the pressure of 2 bar, the residual amount of uncompressed air will be V _air = V _reserv0 ir · Pair = 5 1 - 2 bar = 10 1. This means that in the passage from the initial 50 1 of air (at 10 bar) to the final 10 1 of air (at 2 bar) in equilibrium with the pressure assumed downstream of the pressure reducer 25 a volume of air of 40 1 has been let out of the reservoir 21. Assuming that the volume 11 is 20 1, the liquid initially present will have been emptied out completely; in fact, for a volume of 20 1 with air at a pressure of 2 bar we shall have inside an equivalent volume of uncompressed air of 40 1.