WO2007019852A1

WO2007019852A1 - Pressure-reducing beverage dispensing line

Info

Publication number: WO2007019852A1
Application number: PCT/DK2006/000439
Authority: WO
Inventors: Jan Nørager RASMUSSEN
Original assignee: Carlsberg Breweries A/S
Priority date: 2005-08-12
Filing date: 2006-08-10
Publication date: 2007-02-22

Abstract

The present invention relates to an assembly (1) for dispensing beverage comprising a dispensing line (7) for dispensing a pressurized beverage from a container. The dispensing line (7) comprises at least two sections: a first section (13) having a length L1 and an inner cross- sectional area A1, and a second section (14) downstream of said first section (13), having a length L2 and an inner cross-sectional area A2, where A1 is smaller than A2. The invention further relates to a dispensing line (7) for use in an assembly (1) for dispensing beverage and a method for reducing pressure in a dispensing line (7).

Description

PRESSURE-REDUCING BEVERAGE DISPENSING LINE

Technical Field of the Invention

The present invention relates to an assembly for dispensing beverage comprising a dispensing line for dis- pensing a pressurized beverage from a container, a dispensing line for use in an assembly for dispensing beverage and a method for reducing pressure in a dispensing line.

Background of the Invention

In the field of dispensing devices, different lines for leading pressurized beverage from a container to a dispensing station, such as a dispensing tap, are previously known. Generally, the lines are connected directly to a container, such as a keg, at one end, and to a dispensing tap at the other end. The beverage in the keg is typically under a pressure higher than atmospheric pressure, usually around 1,5-2,0 bar. Such a high pressure at the dispensing tap may result in uncontrollable dispens- ing and possibly unwanted foam formation. Thus it is desirable to reduce the pressure of the beverage on its way from the keg to the dispensing tap.

One known way to reduce the pressure of a beverage on its way from a container to a dispensing tap is by making the dispensing line very long, e.g. 1-5 meters. The pressure loss is proportional to the length of the dispensing line, and thus, the pressure may be reduced to a suitable level by using dispensing lines of a given length. Another way to reduce the pressure in a dispens- ing line is by inserting valves in or in connection with the dispensing line. Such valves may be adapted for reducing the pressure to a predetermined level. Various other funnel-shaped elements may be employed in the same manner as valves. Valves or similar elements may also be comprised within the dispensing tap of an assembly for dispensing beverage, thus being at the end of the dispensing line when it is connected to the dispensing tap.

A number of disadvantages are associated with the known techniques for reducing pressure in a dispensing line. The very long dispensing lines are obviously relatively difficult to handle as well as relatively expensive. Also, a long dispensing line may in itself hold a large volume of beverage. Such a volume of beverage within the tube may become a problem, e.g. when changing kegs, since beverage may spill from detached line. This is both wasteful and unhygienic. The long line is of course especially unsuitable for use in small dispensing assemblies, such as assemblies for use in private homes. Valves or other similar devices inserted in the dispensing line are usually relatively expensive. Valves arranged in the dispensing tap of an assembly for dispensing beverage have the further disadvantage that they have to be thoroughly cleaned each time the dispensing tube is changed in order to avoid hygienic problems.

For some types and uses of dispensing assemblies it may be desirable to employ a number of single-use disposable parts, such as dispensing lines which are disposed of together with an empty keg. This may be done both for convenience reasons, e.g. making the assembly user- friendly, but also for reasons of hygiene, e.g. avoiding contamination of the parts in direct contact with the beverage. Since production cost and ease of handling are major parameters of single-use devices, the above men- tioned drawbacks with the known techniques, namely difficult handling and production as well as high cost, become even more problematic when trying to employ the techniques to provide single-use disposable devices.

There is thus a need for an assembly for dispensing beverage dealing with the above-mentioned disadvantages with the known techniques. Specifically, there is a need for a dispensing line which effectively reduces beverage pressure while at the same time being hygienic, easy to handle and having a low production cost. There is also a need for a dispensing line with all of the above characteristics, which is at the same time suitable for use in a single-use disposable system.

It is an objective of the present invention to provide a new and inventive assembly for dispensing beverage, which deals with the above-mentioned disadvantages with the prior art. It is more specifically an objective to provide a dispensing line which reduces pressure effectively while being hygienic, easy to handle, inexpensive in production, and suitable for use in a single-use disposable system.

Summary of the Invention

The present invention is new and inventive in that it provides an assembly for dispensing beverage comprising a dispensing line for dispensing a pressurized beverage from a container, said dispensing line comprising at least two sections: a first longitudinal section having a length Li and an inner cross-sectional area Ai, and a second section downstream of said first section, having a length L₂ and an inner cross-sectional area A₂, where Ai is smaller than A₂. The matter is, that due to the smaller inner cross-sectional area Ai, the pressure of the beverage is reduced by passing through the first section. The second section with the larger cross-sectional area A₂ may ensure that the beverage obtains flow- and foam-formation properties suitable for dispensing. Such suitable flow- and foam-formation properties may depend upon the type of beverage being dispensed and may also be affected by other parts of an assembly for dispensing beverage.

The dispensing line may comprise an additional sec- tion upstream of the first section, said additional section having a length Lo and an inner cross-sectional area of AQ. This may be a convenient way to achieve the right pressure and flow properties within the dispensing line.

The inner cross sectional area Ao may be greater than Ai. Each section of the dispensing line may have an essentially uniform inner cross-sectional area along its length, such as by having cylindrical sections . An essentially uniform inner cross sectional area may give advantageous flow properties within the dispensing line. The inner cross-sectional area of a section of the dispensing line may vary along the length of said section. This may be desirable for providing a smooth flow of beverage and minimizing turbulence.

The length Li of the first section may be anywhere from around 1% to around 99% of the total length of the dispensing line. For instance, the length Li of the first section may be from around 25% to around 75% of the total length of the dispensing line. Such a relationship between Li and the total length may provide for effective pressure reduction and good flow properties.

The dispensing line may be produced by inserting a first line with an outer diameter D_oi into a second line with an inner diameter D₁2, where D_oi is essentially equal to D₁₂. This is a convenient and inexpensive way of pro- ducing a dispensing line with desirable properties.

The dispensing line may be produced by deformation, heat deformation or rolling. These are all convenient ways of producing a dispensing line.

The dispensing line may advantageously be made of a polymer material and produced by cold rolling. By the dispensing line being produced by cold rolling is meant that the section or sections of the dispensing line with a smaller inner cross-sectional area are formed by cold rolling. Thus, in a specific preferred embodiment, the dispensing line is made from a polymer tube by deformation by cold rolling of a section of the tube to yield a smaller cross-sectional area of that section, thus form- ing the dispensing line. The matter is that producing a dispensing line out of polymer by cold rolling yields a considerably more durable and flexible dispensing line. The dispensing line may be made of an at least partially crystalline polymer, such as PE or PET. Particularly, the dispensing line may be internally stress-free. By the dispensing line being "internally stress-free" is meant that the molecules of the polymer material of the dispensing line are substantially un-aligned. When deforming a material, such as a polymer, the molecules of the material usually align in the direction of deformation. This makes the material more brittle and less flexible. Thus, avoiding the alignment of the molecules increases the durability and flexibility of the produced dispensing line considerably. Internal stress in a polymer material can for instance be visualized by use of polarization filters. This phenomenon is explained by the so-called birefringence of polymer materials that have been exposed to mechanical strain, which again is a result of the align- ment of the polymer molecules in the material.

The present invention is also new and inventive by providing a dispensing line for use in an assembly for dispensing beverage, said dispensing line comprising at least two sections: a first longitudinal section having a length Li and an inner cross-sectional area Ai, and a second section downstream of said first section, having a length L₂ and an inner cross-sectional area A₂, characterized in, that Ai is smaller than A₂.

The present invention is furthermore new and inven- tive by providing a method for reducing pressure in a dispensing line, said method comprising the step of letting beverage flow from a container through a dispensing line comprising at least two sections: a first longitudinal section having a length Li and an inner cross- sectional area Ai, and a second section downstream of said first section, having a length L₂ and an inner cross-sectional area A₂, where A₁ is smaller than A₂. Brief Description of the Drawings

The invention and its many advantages will be described in more detail below with reference to the accom- panying schematic drawings, which for the purpose of illustration show some non-limiting embodiments and in which

Fig. 1 shows an embodiment of an assembly for dispensing beverage, Fig. 2 shows another embodiment of an assembly for dispensing beverage,

Fig. 3 shows an embodiment of a dispensing line in perspective,

Fig. 4 shows another embodiment of a dispensing line in perspective,

Fig. 5 shows an embodiment of a dispensing line in cross-section, and

Fig. 6 shows another embodiment of a dispensing line in cross-section. All the figures are highly schematic and not necessarily to scale, and they show only parts which are necessary in order to elucidate the invention, other parts being omitted or merely suggested.

Detailed Description of Preferred Embodiments ,

Fig. 1 shows an embodiment of an assembly 1 for dispensing beverage comprising a cooling chamber 2, a cooling system 3, a container (not visible) within a pressure chamber 4, a pressure chamber lid 5 with an opening 6 for a dispensing line 7 (not shown) , a dispensing line channel 8, a tower 9, a dispensing tap 10 and a tap actuator 11. In this particular embodiment, the pressure chamber is contained within the cooling chamber. In other embodiments, however, the pressure chamber 4 and the cooling chamber 2 may be one and the same chamber. Such an embodiment is illustrated in fig. 2. Various materials may be used for the assembly 1 for dispensing beverage. The following are the materials used for a specific embodiment of an assembly 1 for dispensing beverage: the walls and door of the cooling chamber 2 may be made of hard plastic, the container may be made of compressible plas- tic such as blended PET, the pressure chamber 4 and its lid 5 may be made of pressure-resistant plastic, the dispensing line channel 8 may be made of hard plastic, the dispensing line 7 may be made of semi-hard plastic, preferably of a flexible nature in order to allow easy ma- nipulation of the dispensing line 7, the tower 9 may be made of metal, the dispensing tap 10 and the tap actuator 11 may be made of hard plastic. Many other materials or combinations of materials could be used for the assembly 1 for dispensing beverage. Fig. 2 shows another embodiment of an assembly 1 for dispensing beverage comprising a combined cooling and pressure chamber 2+4, a cooling system 3, a dispensing tap 10, a tap actuator 11 and a dispensing valve 12. As mentioned previously, in this particular embodiment the cooling chamber 2 and the pressure chamber 4 are combined into one single chamber 2+4, which may serve both purposes .

In fig. 2, the cooling system 3 is illustrated as a peltier cooling system. However, other cooling mecha- nisms, including but not limited to air and liquid cooling, may be employed.

Fig. 3 shows an embodiment of a dispensing line 7 comprising a first section 13 having a length Li, and a second section 14 downstream of said first section 13, having a length L₂. The direction of beverage flow during use is indicated with an arrow. "Upstream" and "downstream" directions are given in relation to the direction of beverage flow during use. During use, the upstream end of the dispensing line 7 may be connected to a container while the downstream end may be connected to a dispensing tap 10 and/or a tap actuator 11. During use, a dispensing valve 12 may be placed in connection with the downstream end of the dispensing line 7. Optionally, the dispensing line 7 may comprise an additional section (not shown) upstream of the first section 13. This additional section may be arranged for connection to a container. In fig. 3, the dispensing line 7 is illustrated as a cylindrical tube with a narrow and wide section. However, the dispensing line may be of any suitable shape, e.g. as illustrated by the embodiments shown in figs. 4-6. The length of the sections of the dispensing line 7 may vary according to the needs and requirements to be met. Since the lengths of the sections determine the pressure- reducing effects and the flow-properties of the dispensing line 7, the lengths may be varied according to specific pressures and flow requirements. The pressure- reduction and flow-properties can be roughly compared to the phenomena observed in so-called Orifice- and Venturi flow meters. The length Li of the first section 13 may for instance be from around 25% to around 75% of the total length of the dispensing line 7. As an example, our research shows that by employing a dispensing line 7 with a length Li of around 350 mm and a length L₂ of around 210 mm, pressure can be reduced from around 1,5 bar at the upstream end of the dispensing line 7 to around atmospheric pressure at the downstream end. It is of course necessary to be very aware of the many factors influencing the pressure of a beverage, e.g. temperature, flow rates, viscosity, gas content, and flow friction, and take these into account when working with means and methods for reducing the pressure of a beverage, e.g. in a dispensing line 7.

Additional embodiments of the dispensing line 7 are illustrated in figs. 4-6. As seen, both the inner and outer diameters and cross-sectional areas of the sections of the dispensing line 7 may vary, both within a given section and between different sections and embodiments. The geometrical shape of the cross-sectional area may also vary, both in a section and between different sec- tions. Both circular (see fig. 5) and non-circular (fig. 6) cross-sectional areas may give beneficial flow- properties depending on the specific needs.

The dispensing line 7 may be produced in a number of manners. A particular embodiment of a dispensing line 7 is the so-called line-within-line (not shown) . This particular embodiment is produced by inserting a first line with an outer diameter D_Oi into a second line with an inner diameter D₁2, where D_oi is essentially equal to Dj₂. This is an easy, fast and inexpensive manner in which to produce a dispensing line 7. Furthermore, it has the additional advantage that the dispensing line 7 has a uniform outer diameter along its entire length, which may be desirable when incorporating the dispensing line 7 into an assembly 1 for dispensing beverage. Other methods of producing dispensing lines 7 include deformation, heat deformation and rolling of lines. A dispensing line 7 as illustrated in fig. 6 may for instance be produced by heat deformation. In a particularly preferred embodiment the dispensing line 7 may advantageously be made of a polymer material and produced by cold rolling. The dispensing line 7 may for instance be obtained by cold rolling of a polymer tube. The cold rolling method is usually only employed for deformation of metals and its application to polymer materials yields both very surprising and beneficial effects. By controlling the deformation rate of the material, e.g. a polymer tube, specific properties of the dispensing line 7 can be obtained. For instance, the fin- ished dispensing line 7 may be substantially free of internal stress, meaning that the polymer material of the dispensing line 7 is substantially free of internal stress and thus considerably more durable and flexible. This is a highly surprising and unexpected advantage of the production by cold rolling. The increased durability and flexibility of the material is particularly relevant for a dispensing line 7 that often has to be rolled up, manipulated and adjusted to fit various assemblies 1. The pressure applied to the polymer material during the cold rolling may vary according to the desired final properties of the dispensing line 7. For instance, the pressure applied may be in the range of about 100 to about 300 gi- gapascal (GPa) . In a specific embodiment the deformation pressure is about 200 GPa. The type of polymer material used for a dispensing line 7 produced by cold rolling may- vary, but particularly preferred materials are at least partially crystalline polymers, e.g. PE or PET. Particular advantages of producing the dispensing line 7 out of a polymer material includes increased flexibility as opposed to e.g. metal, easier and less costly production as well as more convenient, environmental and inexpensive use of the dispensing line 7 as a disposable part.

The dispensing line 7 as well as the method for reducing pressure in a dispensing line 7, may possibly be used separately from the assembly 1 for dispensing beverage. For instance, the disclosed dispensing line 7 may be incorporated into existing dispensing systems and the method of reducing pressure may be practiced by making the required inventive modifications to existing dispensing systems .

Although the invention above has been described in connection with preferred embodiments of the invention, it will be evident for a person skilled in the art that several modifications are conceivable without departing from the invention as defined by the following claims.

Claims

1. An assembly (1) for dispensing beverage comprising a dispensing line (7) for dispensing a pressurized beverage from a container, characterized by said dispensing line (7) comprising at least two sections: a first section (13) having a length L₁ and an inner cross- sectional area Ai, and a second section (14) downstream of said first section (13) , having a length L₂ and an in- ner cross-sectional area Α₂, where Ai is smaller than A2.

2. An assembly (1) according to claim 1, wherein the dispensing line (7) comprises an additional section upstream of the first section (13), said additional section having a length Lo and an inner cross-sectional area of A₀.

3. An assembly (1) according to claim 2, wherein Ao is greater than Ai.

4. An assembly (1) according to any one of the preceding claims, wherein each section of the dispensing line (7) has an essentially uniform inner cross-sectional area along its length, such as by having cylindrical sections .

5. An assembly (1) according to any one of the claims 1-3, wherein the inner cross-sectional area of a section of the dispensing line (7) varies along the length of said section.

6. An assembly (1) according to any one of the preceding claims, wherein the dispensing line (7) is produced by inserting a first line with an outer diameter D_Oi into a second line with an inner diameter D₁₂, where D_Oi is essentially equal to D12.

7. An assembly (1) according to any one of the claims 1-5, wherein the dispensing line (7) is produced by deformation, heat deformation or rolling.

8. An assembly (1) according to any one of the claims 1-5, wherein the dispensing line (7) is made of a polymer material and produced by cold rolling.

9. An assembly (1) according to claim 8, wherein the dispensing line (7) is made of an at least partially crystalline polymer, such as PE or PET.

10. An assembly (1) according to claim 8, wherein the dispensing line (7) is internally stress-free.

11. A dispensing line (7) for use in an assembly (1) according to any one of the preceding claims, characterized by said dispensing line (7) comprising at least two sections: a first section (13) having a length Li and an inner cross-sectional area Ai, and a second section (14) downstream of said first section (13) , having a length L₂ and an inner cross-sectional area A₂, characterized in, that Ai is smaller than A₂.

12. A method for reducing pressure in a dispensing line (7), characterized by said method comprising the step of letting beverage flow from a container through a dispensing line (7) comprising at least two sections: a first section (13) having a length Li and an inner cross- sectional area A_x, and a second section (14) downstream of said first section (13) , having a length L₂ and an inner cross-sectional area A₂, where Ai is smaller than A₂.