The applicant company produces and sells a professional draught beer system named DraughtMaster™ comprising a beverage dispensing system and a chill chamber in which the keg or pack containing carbonated beer is received. The keg or pack containing carbonated beer comprises a flexible bottle or bag, which is exposed to an elevated pressure from the outside for dispensing the beer. The flexible bottle or bag is connected through a dispensing line to a shut-off valve, which is ducted through a channel of the beverage dispensing system and is received in and operated by means of a tap handle of a tapping head housing for operating the shut-off valve between an open and a closed position, i.e. between a beverage dispensing position and a non-beverage dispensing position.
The international patent application WO 2001/092142 A1 discloses a drink dispenser assembly comprising a dispensing line and a shut-off valve. The shut-off valve comprises a first sleeve and a second sleeve which first sleeve is provided with an inlet to an upstream part of the dispensing line and an outlet. The second sleeve is provided with an inlet which interacts with the outlet of the first sleeve and with an outlet. Coupling means are arranged on one of the sleeves which can be moved by the coupling means between a flow position, in which the outlet of the first sleeve is in fluid communication with the inlet of the second sleeve, and a shut-off position in which the outlet of the first sleeve is closed off by the second sleeve.
In the applicant company's previously filed European patent application 07388021.3, publication no. EP 1 982 951 A1, published on 22 Oct. 2008, and similarly in applicant's previously filed international patent application PCT/DK2008/000140 claiming priority from the above-mentioned European patent application, a technique of joining a separate valve element to a sealed-off dispensing line, after the valve element and the dispensing line have been introduced into the tapping head housing as separate elements, is described as the joining is established the first time the tap handle of the tapping head housing is moved from its closed position to its open position.
A later international patent application PCT/EP2010/050592, published on the 5 August as WO 2010/086275 A1, describes a beverage dispensing assembly including a dispensing line and a valve element. The valve element comprises an upstream valve part, a flexible valve part and a downstream valve part. The downstream valve part includes a plug for sealing off a dispensing end of the dispensing line.
The present invention generally relates to the technical field of beverage dispensing assemblies for carbonated beverages including a dispensing line and valve parts cooperating with the dispensing line for opening and closing the dispensing line. In relation to carbonated beverages stored at elevated pressure, the sudden pressure drop between the elevated pressure upstream of the valve and the atmospheric pressure downstream of the valve may cause excessive foaming of the beverage. The foaming is caused by turbulence in the beverage flow in the valve which in turn is due to the high flow velocities generated by the pressure difference between the upstream part of the valve and the downstream part of the valve. The intensity of the turbulence is also depending on other factors such as the extent of stagnation paints in connection with location where the flow detaches from the surface of the valve. At such locations strong vortexes may occur which causes foaming.
It is therefore an object of the present invention to provide an improved beverage dispensing assembly which minimizes the amount of foaming generated during dispensing.
The above objects, the above advantage, and the above feature together with numerous other objects, advantages, and features, which will be evident from the below detailed description of the present invention, are, in accordance with a first aspect of the present invention, obtained by a beverage dispensing assembly to be used in combination with a tapping head, the tapping head including a tapping head housing and a tap handle, the beverage dispensing assembly comprising:
The dispensing end of the dispensing line, the upstream valve part and the downstream valve part makes up the valve of the beverage dispensing assembly. The keg connection end of the dispensing line is fixated to a keg or container which is filled by beverage. The container is typically collapsible for use with a pressurized beverage dispensing system and the beverage is typically a carbonated beverage. The dispensing line may be permanently fixated to the keg or container but also provided as a separate part which is attached to the keg or container during installation of the keg or container in the beverage dispensing system. The flow area of the dispensing line should be substantially circular, i.e. allow for some deviation from the perfectly circular shape.
The tapping head housing typically encloses the dispensing end of the dispensing line, the upstream valve part and the downstream valve part. The tap handle constitutes, the part of the tapping head which the user swings between a horizontal and vertical orientation in order to open and close the valve and thereby control the beverage dispensing in a well known manner. The dispensing line may be any tubing of suitable size and material for conducting beverage.
The upstream valve part is attached about the outwardly oriented surface of the dispensing line adjacent the dispensing end for the purpose of interacting with the downstream valve part. The downstream valve part comprises the plug which controls the beverage flow from the dispensing end of the dispensing line. The upstream valve part and the downstream valve part have cooperating snap lock members which together form a snap lock mechanism.
The applicant has surprisingly found out that by avoiding any vortex formation during the first few moments of opening the beverage flow, foaming of the beverage may be significantly reduced. A vortex formed early during the opening procedure may have a sufficiently large momentum to remain and disturb the flow for several seconds after the valve has reached full open position. When regarding valves which operate by removing a plug from an orifice, during the opening sequence, a small asymmetrical gap may be generated between the dispensing end and the plug where the beverage will stream through before the valve opens up an annular opening between the plug and the dispensing end. At this location, a vortex is generated which will disturb the flow and cause turbulence which will cause foaming even after the valve is full open.
In order to avoid this vortex, an opening procedure of three states is suggested. In the final non-beverage dispensing position, the plug is caused to apply a sealing force onto the dispensing end of the dispensing line for preventing any of the pressurized beverages to leak through the valve. The plug is integral with the downstream valve part, whereas the upstream valve part is fixated, welded or molded to the dispensing line. The sealing force is generated by the snap lock mechanism which, when in the final non-beverage dispensing position, forces the downstream valve part and consequently the plug towards the dispensing end. The downstream valve part should consequently be flexible in order to be able to allow the inwardly oriented snap lock member to snap correctly into an engagement with the outwardly oriented snap lock member of the upstream valve part while allowing the suitable sealing force to be applied by the plug. A suitable material for the downstream valve part and also the upstream valve part is LDPE of a density of 0.92 g/cm3-0.94 g/cm3. A suitable material for the tapping line which should be smooth is MDPE of a density of 0.92 g/cm3-0.95 g/cm3. Alternative materials for the valve parts and the tapping line may be platinum polymer material.
The upstream section of the plug has a circumference corresponding to the inner circumference of the dispensing line, whereas the downstream section of the plug is wider than the inner circumference of the dispensing line. Thus, when in the final non-beverage dispensing position, the wider downstream section of the plug will wedge itself against the dispensing end by the sealing force due to the flexibility of the downstream valve part in combination with the snap lock mechanism constituted by the inwardly oriented snap lock member and the outwardly oriented snap lock member. In this way, the final non-beverage dispensing position is leakage free.
When the user moves the handle, the downstream valve part moves in a downstream direction and the plug follows, the inwardly oriented snap lock member and the outwardly oriented snap lock member will disengage and allow the downstream section of the plug to separate from the dispensing end of the dispending line. No beverage will flow due to the presence of the upper section of the plug in the dispensing line at the dispensing end. Although no pressure-proof seal may be achieved in this way, no significant amount of beverage may pass as the upper section of the plug blocks the passage. This constitutes the intermediate non-beverage dispensing position and will typically be active only for less than a second during the swinging movement of handle.
When the user moves the handle further towards the open position, the valve will be put in the beverage dispensing position. The upstream section of the plug will separate from the dispensing end of the dispensing line in a substantially symmetrical way presenting an annular flow area between the plug and the dispensing end. The flow of beverage will flow through the dispensing end via the annular flow area past the upstream section of the plug and further past the downstream section of the plug towards the outlet of the downstream valve part without encountering any major asymmetries or discontinuations in the flow area. Thus, the generation of stagnation points or flow separation will be very limited as will the occurrence of turbulence and thereby the foaming will be reduced to a minimum.
Closing of the valve is achieved by reversing the above sequence, i.e. moving the downstream valve part via the handle from the beverage dispensing position via the intermediate non-beverage dispensing position to the final non-beverage dispensing position.
According to a further embodiment of the first aspect, the outwardly oriented snap lock member comprises a protrusion and the inwardly oriented snap lock member comprises a groove. Cooperating grooves and protrusions in combination with a flexible downstream valve part define a very suitable snap lock mechanism capable, of engaging when the groove and protrusion are put in registration.
According to a further embodiment of the first aspect, the inwardly oriented snap lock member comprises a protrusion and the outwardly oriented snap lock member comprises a groove. Naturally, the inverse configuration is possible as well and need no further elaborations.
According to a further embodiment of the first aspect, the downstream valve part comprises an indentation for cooperating with the tapping head. In order for the handle to move the downstream valve part, the handle may be connected to a member of the tapping head which engages the indentation of the downstream valve part allowing the downstream valve part to move.
According to a further embodiment of the first aspect, when in the final non-beverage dispensing position, the inwardly oriented snap lock member and the outwardly oriented snap lock member are engaged causing the downstream section of the plug to subject a sealing force onto the dispensing end corresponding to a beverage pressure of 0.1-6 bar, preferably 1-5 bar, more preferably 2-3 bar, most preferably about 3 bar. The above pressure constitutes typical dispensing pressure for carbonated beverages. The plug should preferably apply the same or a higher pressure onto the dispensing end of the dispensing line in order to prevent leakage of beverage.
According to a further embodiment of the first aspect, the third diameter is between 90% and 100% of the first diameter, preferably between 95% and 100% of the first diameter, more preferably between 98% and 100% of the first diameter, most preferably between 99% and 100% of the first diameter. The upstream section of the plug should preferably fill all or most of the flow area of the dispensing line at the dispensing end in order to prevent any significant beverage flow through the valve which could yield the formation of a turbulence enhancing vortex.
According to a further embodiment of the first aspect, the upstream valve part comprises a first flange, the downstream valve part comprises a second flange cooperating with the first flange for guiding the downstream valve part when moving in relation to the upstream valve part and providing a sealing force between the downstream valve part and the upstream valve part. In order to ensure that the downstream valve part and the upstream valve part are sealed together and that the plug assumes a correct position when closing the valve, i.e. avoiding that the plug assumes a skewed and non-sealed position at the dispensing end of the dispensing line, the first and second flanges may interact to guide the downstream valve part when moving in relation to the upstream valve part.
According to a further embodiment of the first aspect, the outwardly oriented snap lock member is located at the first flange and the inwardly oriented snap lock member is located at the second flange. Preferably, the first and second flanges constitute the areas of contact between the downstream valve part and the upstream valve part and consequently, also the position for the inwardly oriented and outwardly oriented snap lock members.
According to a further embodiment of the first aspect, the downstream valve part comprises a third snap lock member and the upstream valve part comprises a fourth snap lock member, the third snap lock member and the fourth snap lock member engaging when in the beverage dispensing position, whereas the third snap lock member and the fourth snap lock member disengage when in the intermediate non-beverage dispensing position or when in the final non-beverage dispensing position. In order to achieve a well defined full open position, additional snap lock members may be used for achieving a snap lock mechanism which will engage when the full open beverage dispensing position is achieved.
According to a further embodiment of the first aspect, the downstream valve part and the plug are integrally cast as a unitary body. Preferably, the downstream valve part and the plug may be of the same material and integrally cast in order to achieve the high precision which will be required for achieving a well defined closing of the valve.
According to a further embodiment of the first aspect, the downstream valve part defines a tapering from the second diameter to the third diameter. In order to allow the downstream section of the plug to wedge into the dispensing end of the dispensing line and to allow a smooth flow when the valve is open, the plug may define a tapered shape in the interconnection between the upstream section and the downstream section.
According to a further embodiment of the first aspect, the third diameter exceeds the first diameter by 1%-100%, preferably 2%-75% more preferably 5%-50%, most preferably 10%-20%. In order to provide a pressure tight seal at the dispensing end, the diameter of the downstream section should exceed at least the inner diameter of the dispensing end.
According to a further embodiment of the first aspect, the upstream valve part is being molded, welded or glued onto the dispensing line. In this way, the positioning of the upstream valve part may be achieved with high accuracy, which in turn is critical for the correct movement of the plug.
According to a further embodiment of the first aspect, the dispensing line, the downstream valve part and the upstream valve part are made of a flexible polymeric material such as PE. The above materials are suitable due to their flexibility.
The above objects, the above advantage, and the above feature together with numerous other objects, advantages, and features, which will be evident from the below detailed description of the present invention, are, in accordance with a second aspect of the present invention, obtained by a method of dispensing beverage by providing a beverage dispensing assembly in combination with a tapping head, the tapping head including a tapping head housing and a tap handle, the beverage dispensing assembly comprising:
a dispensing line having a dispensing end and a keg connection end, the dispensing line being flexible and defining at the dispensing end an inner substantially circular flow area having a first diameter,
the method comprising the following steps:
The method according to the second aspect is preferably used together with the assembly according to the first aspect.
The dispensing line 20 extends into the upstream valve part 26 and defines a dispensing end 46. The dispensing end 26 constitutes the end opening of the dispensing line. The upstream section 38 of the plug 36 is circular cylindrical and has a circumference corresponding to the circumference of the dispensing end 46 and in the present final non-beverage dispensing position, the upstream section 38 has been inserted into the dispensing end 46. The downstream section 40 defines a tapering from the upstream section 38 to a circumference exceeding the circumference of the dispensing end 46. In the present final non-beverage dispensing position, the downstream section 40 of the plug 36 applies a sealing pressure onto the dispensing end 46, which sealing pressure is caused by the snap lock mechanism in combination with the flexibility of the downstream section 40.
It is evident that although the present invention has been illustrated here with reference to particular embodiments of the beverage dispensing assembly, various modifications may be evident to the skilled person.
10. Beverage dispensing system
12. Tapping head
14. Tapping head housing
16. Handle
18. Beverage glass
20. Dispensing line
22. Pressure chamber
24. Valve
26. Upstream valve part
28. Downstream valve part
30. Member
32. Indentation
34. Beverage outlet
36. Plug
38. Upstream section
40. Downstream section
42. First snap lock member
44. Second snap lock member
46. Dispensing end
48. Annular gap
50. Pass through channel
Number | Date | Country | Kind |
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14169623.7 | May 2014 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2015/061352 | 5/22/2015 | WO | 00 |