GB2314071A - Drinks dispensing apparatus - Google Patents

Abstract

Drinks dispensing apparatus comprises a storage cask 1 for beer to be dispensed from a dispensing head 2 by a hand operated lever 4. The cask is fitted with a peg 6 above the level of beer in the cask. The peg operates as a one-way pressure-operated check valve that is biased closed when the pressure of carbon dioxide in the container is greater than atmospheric pressure and is forced open if the carbon dioxide pressure in the container is less than atmospheric to allow air to pass into the container. The invention prevents carbon dioxide released from the surface of the beer from escaping form the cask and thereby affecting the quality of the beer. Moreover, the peg allows air to pass into the cask when beer is being dispensed to prevent a partial vacuum being created.

Description

DRINKS DISPENSING APPARATUS The present invention relates to drinks dispensing apparatus and more particularly to dispensing beverages such as cask conditioned beer from its container whilst ensuring the quality of the beer is maintained.

It is well known in the licensed trade that the quality of a cask conditioned beer deteriorates during use. After the first 24 hours of being on sale the beer in the cask begins to loose quality in terms of taste and body. Generally from the third day of use onwards the condition of the beer deteriorates rapidly and it soon becomes unpalatable.

Beer casks are barrel shaped with an outlet tap hole at the extremity of an end face. A filling hole is provided in the barrel at the maximum outside diameter. When the barrel is filled at the brewery both holes are closed with specially designed bungs made of either plastics or wood. On delivery to the public house the cask is set up on a stillage with the outlet tap hole at its lowest position so leaving the filling hole at the highest point of the barrel. Settling of the beer takes a day and the cask can then be tapped and vented. A tap with a tapered stem is hammered through the weakened central portion of the bung in the outlet tap hole to give a good seal. The bung sealing the filling hole has a separate plastic central "tut" which is knocked through into the beer. When it has been established the beer has settled and is of desired quality the filling hole is sealed with a "hard" peg (usually of plastics) until required for sale.

With the full container being sealed from the ingress of air the beer will mature and maintain its quality and condition for a reasonable number of days. When the beer is required for sale a pipe of a pump is connected to the outlet tap and the "hard" peg is replaced with a "soft" peg made of cane. This prevents the free movement of air and limits the possibility of air borne yeast getting into the cask which would adversely effect the quality of the beer.

When beer is dispensed from the cask the soft peg permits air to pass through it into the cask to replace the volume previously occupied by the dispensed beer thereby ensuring the cask interior is approximately at atmospheric pressure. When the beer is not being dispensed carbon dioxide given off by the beer is allowed to escape to atmosphere in the opposite direction through the aperture. It is the escape of carbon dioxide that causes the deterioration in the quality of the beer. It will be appreciated that the greater the exposed surface area of the beer the greater is the rate of carbon dioxide loss and that as the volume of beer in the barrel-shaped cask decreases the surface area of the beer increases until it reaches a maximum when the cask is half empty at which point the deterioration rate is a maximum.

During periods of little or no use i.e. outside of trading hours in a public house it is known to replace the soft wooden peg with a "hard" peg manufactured from plastics. This hard peg fits tightly in the aperture and prevents the escape of carbon dioxide from the cask but has to be replaced by the soft peg to permit beer to be dispensed since it also prevents the ingress of air to the cask. If the hard peg is fitted when the beer is initially dispensed a vacuum is created in the cask making it impossible for more beer to be drawn from the cask. It will be appreciated that the continual swapping of the wooden and plastics pegs is tiresome and time consuming particularly as cask conditioned beers are generally stored in the cellar of the public house.

One known alternative to using hard and soft pegs is to connect a continuous pressurised source of carbon dioxide to each cask so that the level of carbon dioxide content of the beer is maintained at all times. However, the equipment required to ensure satisfactory operation is relatively expensive and is time consuming to fit every time casks require replacement.

With the resurgence in popularity of cask conditioned beers in recent years there is a need in the licensing trade for a simplified way of maintaining and managing cask beers. At present the publican has to order just enough casks of beer to match the predicted demand over a very short period of time to ensure that the beer condition can be maintained satisfactorily over that period. Consideration has to be given to whether each particular beer will be slow or fast selling and it will be appreciated that this is often difficult to predict. Often the publican is left with a significant volume of waste beer.

It is an object of the present invention to obviate or mitigate the aforesaid disadvantages.

According to the present invention there is provided drinks dispensing apparatus comprising a storage container for carbonated liquid to be dispensed, a dispensing head, a conduit between the container and the dispensing head and means for transferring liquid from said container to said dispensing head via the conduit, wherein the container is fitted with a one-way pressure-operated valve that is biased closed when the pressure in the container is greater than atmospheric pressure and is forced open if the pressure in the container is less than atmospheric to allow air to pass into the container.

The purpose of the valve is to ensure that the beverage is maintained in the container at a desirable level of taste quality.

Thus carbon dioxide released from the surface of the liquid is prevented by the valve from escaping from the container and thereby impairing the quality of the liquid to be consumed. Moreover, when the liquid is being dispensed air is permitted to enter the container from atmosphere to replace the dispensed volume thereby preventing a partial vacuum being created in the container. The presence of a partial vacuum would make further dispensing of the liquid difficult or impossible.

Preferably the one-way pressure operated valve is in the form of a peg fitted in an aperture of the container, the peg having a bore connecting the interior of the container to atmosphere, the bore being closeable by a valve member. The valve may be biased closed by the pressure of carbonating gas escaping from the surface of the liquid.

The valve member preferably comprises a flexible diaphragm retained in a bore of the peg and deflectable between valve open and valve closed positions. The peg may have a plug member having an aperture that communicates with the peg bore and with atmosphere when the valve is open and is sealed when the valve is closed.

Preferably the flexible diaphragm is housed adjacent the plug member aperture so that in the valve closed condition it seals the aperture to prevent communication with the peg bore and in the valve open configuration the diaphragm moves away from the plug member to permit communication between the plug aperture and the peg bore.

Preferably the valve diaphragm comprises a disc having a arcuate cut-out to define a deflectable membrane. The cut-out may be of horse-shoe shape.

Preferably the peg comprises a head that protrudes from the container and in which the plug member is received, and an elongate tapered portion that extends into the container.

The container may be a cask and the liquid may be beer.

A specific embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic side view of drinks dispensing apparatus of the present invention; Figure 2 is a sectioned side view of a cask peg including a one-way pressure operated valve of the present invention; Figure 3 is a plan view of a diaphragm of the valve of figure 2; and Figure 4 is a sectioned side view of an alternative embodiment of the present invention.

Referring now to the drawings, there is shown in figure 1 a cask 1 of beer traditionally stored in a cellar of a public house and connected to a dispensing outlet 2 fitted at the trading bar of the public house. Beer is transferred from the cask 1 to the dispensing outlet 2 via a pipe 3 using conventional means such as an electric or gas driven pump (not shown) activated by a hand-operated lever 4.

At the top of the cask, above the level of the beer, is an aperture 5 occupied by a peg 6 which is shown in more detail in figure 2.

The peg 6 is of hollow cylindrical configuration and comprises a head 7 of constant diameter integrally connected to an elongate tapered portion 8. The head 7 has a counterbore 9 that meets with a smaller constant diameter bore 10 of the tapered portion 8. An annular step ii between the two bores 9, 10 defines a valve seat for a valve diaphragm 12 that is retained and sealed in the counterbore 9 of the head 7 by a plug 13.

The valve diaphragm 12, shown in figure 3, comprises a thin plastics or moulded soft rubber disc having a thin horse-shoe shape cut-out 14 to define a central flexible valve membrane 15.

The plug 13 is a press fit in the counter bore 9 and has a central axially extending bore 16 aligned with the bore 10 in the tapered portion 8, the communication between the two bores 10, 16 being blocked by the presence of the valve diaphragm 12. A flat end surface 17 of the plug 13 abuts the valve diaphragm 13 to seal it against the valve seat 11 and to prevent deflection of the flexible membrane 15 to the upwardly as shown in figure 2.

In use, when beer is not being dispensed the slow natural release of carbon dioxide from the beer in the cask 1 exerts a pressure on the valve diaphragm 12 in the direction of arrow X as shown in figure 2. Under this pressure the membrane 15 seals the plug bore 16 so that carbon dioxide cannot escape. The build up of pressure in the cask 1 prevents further release of carbon dioxide from the beer and thus prevents its condition from deteriorating significantly.

When beer is dispensed the internal pressure of the cask 1 drops. If the atmospheric pressure outside the cask 1 exceeds the internal pressure it exerts a pressure in the direction of arrow Y and the membrane 15 is forced away from the end surface 17 of the plug 16 thereby permitting air to enter the cask 1 through the plug bore, around the deflected membrane, through the cut-out 14 and through the bore of the tapered portion of the peg. This ingress of air prevents a partial vacuum being created in the cask.

An alternative design is shown in figure 4 in which parts corresponding to those of figures 2 are indicated by the same reference numerals increased by 100 and are not further described except insofar as they differ from their counterparts in figure 2. In this design the bore 110 is stepped at approximately mid-length to provide an annular abutment surface 120 for one end of a compression spring 121. The other end 122 of the spring 121 abuts the valve membrane 115 and applies a light biasing force to ensure a positive seal during build up of the internal pressure in the cask 1.

The end of the bore 110 adjacent the valve membrane 115 has a radially outward taper 123 to ensure the internal carbon dioxide pressure acts over an increased area of the valve membrane 115. The flat end face 117 of the plug 113 has an annular recess 124 and a radially enlarged central axially extending bore 116.

This design provides for a narrow valve membrane seat 111 that allows for more effective sealing. The provision of a smaller surface area on the valve seat 111 enables it to engage with the rubber valve membrane 115 more effectively and cause the area of the rubber to deflect locally to provide a better quality seal. The enlarged central bore 116 increases the exposed area of the valve membrane 115 on which the atmospheric pressure is applied so as to enable an increased volumetric rate of entry of atmosphere into the cask 1 when required.

The exposed face of the plug 113 has an enlarged counterbore 109 that is fitted with an air filter 125 made, for example, from open cell foam.

It will be appreciated that by using the peg described above the need to visit the cellar at the end or start of each trading session to swap cask pegs from soft to hard or vice versa is eliminated. Moreover, the condition of the beer is maintained at a high quality since there is no escape of carbon dioxide when sales are slow or outside of trading hours and wastage is thereby reduced.

Claims (16)

1. Drinks dispensing apparatus comprising a storage container for carbonated liquid to be dispensed, a dispensing head, a conduit between the container and the dispensing head and means for transferring liquid from said container to said dispensing head via the conduit, wherein the container is fitted with a one-way pressure-operated valve that is biased closed when the pressure in the container is greater than atmospheric pressure and is forced open if the pressure in the container is less than atmospheric to allow air to pass into the container.

2. Drinks dispensing apparatus according to claim 1, wherein the valve is biased closed by the pressure of carbonating gas escaping from the surface of the liquid.

3. Drinks dispensing apparatus according to claim 1 or 2, wherein the one-way pressure-operated valve is in the form of a peg fitted in an aperture of the container, the peg having a bore connecting the interior of the container to atmosphere, the bore being closeable by a valve member,

4. Drinks dispensing apparatus according to claim 3, wherein the valve member comprises a flexible diaphragm retained in a bore of the peg and deflectable between valve open and valve closed positions.

5. Drinks dispensing apparatus according to claim 4, wherein the peg has a plug member having an aperture that communicates with the peg bore and with atmosphere when the valve is open and is sealed when the valve is closed.

6. Drinks dispensing apparatus according to claim 5, wherein the flexible diaphragm is housed adjacent the plug member aperture so that in the valve closed condition it seals the aperture to prevent communication with the peg bore and in the valve open configuration the diaphragm moves away from the plug member to permit communication between the plug aperture and the peg bore.

7. Drinks dispensing apparatus according to claim 5 or 6, in which the valve diaphragm comprises a disc having a arcuate cut-out to define a deflectable membrane.

8. Drinks dispensing apparatus according to claim 7, wherein the cut-out is of horse-shoe shape.

9. Drinks dispensing apparatus according to any one of claims 5 to 8, wherein the peg comprises a head that protrudes from the container and in which the plug member is received, and an elongate tapered portion that extends into the container.

10. Drinks dispensing apparatus according to any preceding claim, wherein the container is a cask and the liquid is beer.

11. Drinks dispensing apparatus according to any preceding claim wherein the valve is additional biased towards the closed position by a mechanical biasing device.

12. Drinks dispensing apparatus according to claim 11. wherein the mechanical biasing device is a spring.

13. Drinks dispensing apparatus according to any preceding claim wherein the valve is constructed from resilient material.

14. Drinks dispensing apparatus to claim 13, wherein there is provided a valve seat designed to deflect locally the resilient valve material to ensure effective sealing.

15. Drinks dispensing apparatus according to any preceding claim wherein there is provided an air filter to filter incoming atmosphere.

16. Drinks dispensing apparatus substantially as hereinbefore described with reference to the accompanying drawings.