GB2313824A - Dispensing beverages - Google Patents

Abstract

A unit (30) having a main cylindrical body portion (32) defining a bore (33) that is attached to the dispense tap in a public house bar, and which is internally screw threaded (37) at its lower end. The unit (30) has a manually operable adjustment member (38), a movable member (40), and an orifice plate (42). The orifice plate (42) has a central plate (47) provided with a central hole (48) and five peripheral holes (50). The position of a spigot (64) in the central hole (48) determines the flow through the peripheral holes (50). The unit (30) enables the user to determine the quality of the head on the beer dispensed.

Description

IMPROVEMENTS IN AND RELATING TO DISPENSING BEVERAGES This invention relates to dispensing beverages, especially but not exclusively beer.

By beer we mean beer and the like, such as beer, ale, porter, lager, stout and cider.

The head that a beer has is considered by many drinkers to be very important. Much effort has been devoted to foaming agents/additives. A lot of effort has gone into designing beer dispense nozzles so as to create a good, deep, creamy, head. Work has gone into having the correct dissolved gas content in the beer to achieve a good head. Over the past few years there have been beers launched on the UK market that are dispensed from a tap on a bar as a volume of white foaming beer which then settles out to form a body of clear beer topped by a creamy head.

This was traditionally the preserve of stouts such as Guinness (Trademark), but is now also known for ales such as Caffreys (Trademark) and even lagers such as Carling Premier (Trademark).

A dispense nozzle for a beer tap that is to dispense, say, Caffreys has a spout and an orifice plate. The orifice plate has several (typically five) small holes in it, through which the beer is forced during dispensing of the beer. The brewery design the orifice plate knowing the temperature at which the beer is to be dispensed, the speed of delivery of the beer/pressure drop over the orifice plate, and the dissolved carbon dioxide and nitrogen content of the beer. They can select the size and number of the holes in the orifice plate to give the desired appearance to the just dispensed beer, and to achieve a desired time for the pint (or other volume) of beer to settle out to a body of clear beverage topped by a creamy head.

According to a first aspect of the invention we provide a beverage dispense unit having fixed flow path means comprising at least one fixed flow hole or passageway, and variable flow path means comprising a variable flow hole or passageway, there being adjustable flow control means adapted to adjust the variable flow path means.

This enables us to provide a dispense unit that is capable of dispensing highly nitrogenated beverage, and yet is adjustable to allow the user (e.g. barman) to compensate for variations in parameters that effect the appearance of just delivered beer, and the settling time, and the head that eventually settles out.

The fixed flow path means preferably comprises an orifice plate having one or more holes through it.

In the prior art, such as is shown in Figure 1 of the drawings that accompany this application, the orifice plate is suitable for one use only.

The size of the holes is selected to give a good head for a particular chosen carbon dioxide concentration in the beverage, a particular Nitrogen concentration (Nitrogen is important for making creamy heads with lots of small bubbles that last a long time), and a particular temperature, and for a particular speed of flow through the orifice plate/pressure drop.

Unfortunately, much as the Breweries would like to have every public house maintain consistent temperature of beer at the point of delivery, this can vary from place to place, and indeed from day to day in at the same place. Furthermore, the pressure drop across an orifice plate may depend upon the particular beer pump and may vary from public house to public house. Even the dissolved Nitrogen and carbon dioxide content of the beer may vary between different brews of the same beer.

Thus in practice the head on a pint of a particular brand of beer can vary from public house to public house, and from day to day within the same public house. This is especially true of high nitrogen beers that are delivered as a pint of foamy proto-head that then settles out over a minute or so to about the same volume of cleared beer plus true head. The settling out time also varies with the temperature, pressure and gas content.

The present invention allows the barman to compensate for changes in parameters that effect the beer delivery by adjusting the adjustable flow control.

Preferably adjustment of the adjustable flow control not only influences the foaming of beer passing through the variable flow path means but also alters the pressure drop over the fixed flow path means and so alters the foaming characteristics caused by the fixed flow path means.

One further advantage of having a dispense unit with variable flow path means is that we can use throughout our range of different beverages fewer orifice plates with different size holes. At present each (or nearly each) brand of beer needs an orifice plate with different sized holes. If we have 15 or so different orifice plates in our parts inventory this gives the opportunity to fit the wrong one to a beer dispense tap, and possibly keep that tap in operation until the correct orifice plate is located and fitted. Furthermore, if a landlord wants to change the beer he keeps, or even dispenses from a particular tap, may need to change the orifice plate.

This can be awkward and inconvenient, and even expensive. Some landlords may not bother to change the orifice plate and instead dispense the wrong beverage through an existing orifice plate, which clearly could result in a pint having the "wrong" just-dispensed appearance.

By having a dispense unit that can be adjusted we can allow the barman the opportunity to adjust the same unit to dispense different beers.

Ideally we can use just one kind of dispense unit that is suitable, with appropriate adjustment, for all of (or several of) our beers. This has a reduction in maintenance/servicing when the brand of beer that is dispensed is changed, and avoids problems associated with having many different orifice plates which are not all suitable for all beverages.

Figure 2 of the accompanying drawings shows another kind of known beer dispense tap, but this is not suitable for dispensing high nitrogen beers.

The fixed flow path means has a substantial influence on the appearance and foaming of the dispensed beverage. Preferably the fixed flow path means comprises an orifice plate having at least one hole, and most preferably a plurality of holes.

The variable flow path means preferably comprises a spigot or valve member which co-operates with a hole, movement of the spigot (preferably axially towards or away from the hole) controlling the size of the variable flow passageway. The spigot is preferably associated with a screw-threaded member for axial movement.

The adjustable flow control means is preferably manually adjustable. The adjustable flow control means preferably comprises a member provided on a dispense nozzle of the unit, most preferably at the bottom end of the nozzle.

The orifice plate preferably defines the flow hole of the variable flow path means.

The variable flow hole is preferably of much larger size than the fixed flow holes. The fixed flow holes have a diameter preferably in the range 0.6mm to 1.1mum. There are preferably 2 to 10 fixed flow holes, preferably 4 to 7, and most preferably about 5.

The area of the fixed hole(s) need not be circular, but may take other shapes, for example slotted, square, or any configuration that achieves a satisfactory total area. Similarly, the variable flow hole need not be circular.

The orifice plate preferably has spring biasing means to bias it against a seating. We might provide an O-ring to provide the clenching force.

The unit may comprise a member, such as a nozzle, having a bore in which is provided the orifice plate and the adjustable flow control means.

There may be an expansion chamber provided downstream of the fixed flow path means. The expansion chamber may be adapted to increase in volume as the variable flow path means is opened to increase the flow through the variable flow means. A movable member may define in part the expansion chamber and also have provided associated with it one of the hole or valve member of the variable flow means.

There may be a flow passageway for beverage defined between the movable member and a nozzle body.

There may be a flow passageway defined inside the movable member.

Preferably the movable member is not detachable from the nozzle.

A method of controlling the foaming of beverage when it is dispensed comprising providing fixed dispense orifices or passageways, providing variable dispense means, and adjusting the variable dispense means, the overall foaming of the beer being influenced by the fixed dispense orifices as modified by the effect of the variable dispense means.

Preferably the method comprises reducing or increasing the pressure drop across the fixed dispense orifices by adjusting the variable dispense means.

Preferably the method comprises turning manually operable adjustment. means, preferably through 3600 or less for the full range of flow variation. Preferably the adjustment means is infinitely variable, or substantially so.

According to a third aspect of the invention we provide a method of compensating for variations in temperature, pressure, and gas content of a beverage as it is delivered by providing both fixed and variable orifices, and varying the variable orifices within a predetermined range.

An embodiment of the invention will now be described by way of example only with reference to the accompanying drawings of which: Figure 1 shows a prior art beer tap that has in it an orifice plate; Figure 2 shows another, different, prior art beer dispense nozzle that is suitable for dispensing beer that has little dissolved nitrogen content; Figure 3 shows a new dispense nozzle for beer; Figure 4 shows the dispense nozzle of Figure 3 in exploded format; Figures 5 and 6 show details of components of the nozzle of Figure 3; and Figures 7 and 8 show the flow of beer through the nozzle with it in two different configurations.

Figure 1 shows a beer tap 10 having a nozzle 12, a manually operated control lever 14, and an orifice plate 16 held inside the tap, just above the nozzle 12. The orifice plate 16 has a plurality of small holes 18 extending through it.

The beverage is forced through the holes 18 and this causes the release of gas bubbles which cause the beer to foam, giving a pint of creamy beverage which settles out after a minute or so to a pint of beer with a thick (eg 1 inch) head of creamy, dense, appearance. The beer is typically nitrogenated (eg to 20 to 40ppm) to give a creamy head of small bubbles.

As discussed in the introduction to this patent application, the foaming and head stability is affected by temperature, the pressure of the beer, the carbon dioxide and nitrogen gas content of the beer, and the orifice plate 16. The plate 16 is not suitable to dispense all kinds of beers, and indeed, is usually only suitable to dispense one particular brand of beer and ideally under only one set of conditions. There is no manual adjustment possible.

Figure 2 shows another beer tap nozzle that has a pipe 21 defining an orifice 22 and a screw threaded end cap 23 which has a cone 24 which in use co-operates with the orifice 22 to define an annular aperture of variable cross-sectioned area (and inner radius).

Large holes 25 are provided in the end cap 23 to allow the beer to leave an expansion chamber 26 defined between the end of the pipe 21 and the side of the end cap 23. Unscrewing the end cap 23 does not increase the volume of the expansion chamber by much (perhaps by a few percent).

The nozzle of Figure 2 is used in relatively flat beers, beers which have no nitrogen content. Manual adjustment of the end cap 23 allows for manual variation of the head produced, but the nozzle is not suitable for heavily nitrogenated beers because it is too coarse in its adjustments. The barman would need to be too precise in his adjustment of the nozzle to have any benefit in controlling the dispense of nitrogenated beers.

The end cap can be unscrewed completely after about 3 or 4 turns.

It can be lost, or even deliberately removed by bar staff who do not care what the dispensed pint looks like, preferring instead to dispense the pint as fast as possible (perhaps so as to serve more customers per hour).

Some bar managers have been known to remove the end caps to allow more pints per hour to be dispensed (but of poorer appearance) rather than pay for extra bar staff to meet the number of customers who want a drink.

Such customers get a drink, but do not experience the full aesthetic experience of a properly poured and served pint. For drinks which are intended to settle over a period of time, and perhaps need topping up again before they are served, the temptation for some bar staff to remove the end cap is even greater.

Figures 3 to 6 show our new beverage dispense unit 30. The unit 30 has a main cylindrical body portion 32 which defines a bore 33 that is internally screw threaded (referenced 34) at its upper end to attach to a metal pipe 36 of the dispense tap in the public house bar, and which is internally screw threaded, referenced 37, at its lower end. The unit 30 also has a manually operable adjustment member 38, a movable member 40, and an orifice plate 42.

The body portion 32 has a radially inwardly projecting flange 44 which defines an abutment in the bore 33 and a radially inward step which defines a second abutment surface 46.

The orifice plate 42 has a central plate 47 provided with a central hole 48 of about 3mm diameter and five peripheral holes 50 on an imaginary circle, each hole 50 being of about 0.6mm to 1.lmm in diameter. The central plate is about 0.75 to 1.Omm thick. A peripheral lip, or spring cup, 52 projects from the upper surface of the plate 47. In use the lip 52 abuts against the end face of the pipe 36 and is compressed a little axially, urging the plate 42 against the annular flange 44. The lip 52 may also help to seal the join of the unit 30 to the pipe 36.

The movable member 40 has a head portion 54 and a tail portion 56. The head and tail portions may be made as two components (possibly of different materials) or they could be integrally formed. The head portion 54 has a cylindrical body portion 58 which carries a central cylindrical projection 60 that is provided with an annular abutment shoulder 62. A spigot, or valve, projection 64 extends from the projection 60 and has frustro conical side walls that taper inwardly at 10 .

The diameter of the valve projection 64 is substantially the same (but just less) than that of the hole 48 in the orifice plate. As shown in Figure 3 the valve projection 64 can in its fully closed position project through the hole 48, with the shoulder 62 abutting the underside of the plate 42.

The hole 48 can effectively be sealed closed by the valve projection 64 without the contact being a tight friction fit (the surface tension and viscosity effects of a fluid will tend to prevent flow of the beer through a close-fitting pair of surfaces).

The valve projection can be moved axially way from the orifice plate as will be described later to open the hole 48 to flow of beer. The conical taper of the valve projection 64 helps to centre it as it is advanced into the hole. It maybe retractable completely out of the hole.

The tail portion 56 is best shown in Figures 4 and 6 and has a transverse cylindrical flange plate 66 from which extend three fins 68.

The fins have a portion of the same radial projection as the flange 66, an inwardly stepped portion 70, and a tapering portion 72.

The manually operable adjustment member 38 is a tubular member having a through bore 74 which is inwardly stepped at its lower end. The lowermost portion of the member 38 is a knurled hand-operated turning knob 76. An externally screw threaded region 78 is provided, the screw thread of which co-operates with the thread 37. A resilient O-ring 80 is provided towards the upper end of the member 38. This prevents liquid from passing down to the threads 37 and 78.

The movable member 40 is a tight friction fit inside the bore 74, with the stepped regions 70 of the fins 68 being inside the bore and the flange 66 abutting the upper end face of the tubular adjustment member 38.

The movable member is carried by the adjustment member 38 for axial movement towards and away from the orifice plate 42 (which is in a fixed position). They move as one component.

Figure 7 shows the nozzle in its fully closed configuration.

The valve projection 64 extends through the hole 48, with the shoulder 62 abutting against the plate 42. Substantially no beer flows through the hole 48. All of the beer flows through the fixed orifice plate holes 50. These are very small and produce a lot of small bubbles in the beer, which is dispersed very turbulently, and is very cloudy when just dispersed. The beer takes a long time (about 1 minute, or even 90 seconds) to settle down to a clear body with a good head above it, but when it does it has a deep head of small bubbles that is creamy and stable.

(It will be appreciated that we propose dispensing a nitrogen rich beer).

The beer is typically dispensed at between 2"C and 13"C.

There is an expansion chamber 90 (see Figures 7 and 8) defined between the head portion 54 of the movable member and the orifice plate (and the bore of the nozzle 32). With the adjustment member 38 fully closed the expansion chamber is at its smallest volume.

The axial distance from the rear face of the plate 42 and the upper surface of the portion 58 of the movable member is about 2mm. This means that there is not enough room to develop large bubbles and the bubbles in the beer are small (as well as tending to be small because the beer has been forced through the very small holes 50). The beer flows from the expansion chamber, past the side walls of the head portion 54, past the flange 66, and into the spaces between the fins 68, into the central bore of the adjustable member 38 and hence into the pint (or other volume) glass.

Figure 8 shows the adjustable member in its fully open position.

This is just one 360C rotation of the member 38. The valve projection 64 has been retracted axially and there is now an annular flow path between the part of the plate 42 that defines the hole 48 and the valve projection 64. The expansion chamber 40 is also significantly bigger because the head portion (which part-defines it) has moved away from the plate 42. The gap between the plate 42 and portion 58 increases from 2mm to 3.8mm when the moveable member is fully displaced. Thus the valve projections 64 clears the hole in the plate, but still creates a disturbed flow through the hole 48.

With the adjustable member in its open position there is less flow through the holes 50. Indeed we could arrange things such that there was substantially no flow through the holes 50, but we prefer to have at least some flow through them. This ensures a minimum head effect.

There is a mechanism (not shown) to prevent the removal of the adjustable member 38. This mechanism could just be a stop on the screw threads, or some other stop associated with the movable components.

The annular flow path between the valve projection and the hole 48 is of larger flow cross-section than the holes 50 and so larger bubbles tend to form in the beer, giving a coarser head that settles out faster. The fact that the expansion chamber 90 is also bigger also tends to increase the size of the bubbles, again giving a coarser head that settles out faster.

Of course it will be appreciated that the adjustment of the member 38 (and hence the degree of opening of the hole 48) is infinitely variable under the manual control of the user: he simply turns the knob 76 through a greater or small angle to vary the flow through the hole 48.

Once there is flow through hole 48 there will be a reduction in flow through holes 50.

Adjusting the variable flow valve has the effect of altering the pressure drop over the fixed orifices 50, which also alters the degree of, and quality of, foaming and head formation.

The fact that the beer flows through the narrow annular channel between the outside surface of the head portion 54 and the wall of the bore 33 is believed to calm the beer and improve the head (make it smoother). It gives added control. The beverage is forced to have substantially laminar flow in that region and this is believed to reduce the agitation of the beer.

The barman can now compensate for variations in temperature and pressure of his beer, and for variations in gas content (whether that be because the batch of beer has a varied gas content or because the brand of beer has been changed), to give a well presented glass of beverage which is turbulent initially but settles out to give a good head above a clear body. However, there are limits on the degree of control the barman has: he cannot go beyond the fully open position, which is set by the equipment (ie the Brewery).

The components of the dispense unit are preferably made of mouldable plastics materials (e.g. ABS) suitable to come into contact with food. Some of the precision components (e.g. the orifice plate and/or plunger of the valve) may be made of metal, e.g. stainless steel, if that is necessary or desirable.

We may have a dispense device in a can, or other container, which has fixed and variable dispense orifices, with the variable orifices being adjustable by the user.

Claims (28)

1. A beverage dispense unit having fixed flow path means comprising at least one fixed hole or passageway, and variable flow path means comprising a variable hole or passageway, there being adjustable flow control means adapted to adjust the variable flow path means.

2. A beverage dispense unit according to claim 1, in which the fixed flow path means comprises an orifice plate having at least one fixed hole.

3. A beverage dispense unit according to claim 1 or claim 2, in which the variable flow path means comprises a spigot or valve member which co-operates with a hole, movement of the spigot controlling the size of the variable passage.

4. A beverage dispense unit according to claim 3, in which the spigot or valve member is adapted to move axially towards or away from the hole.

5. A beverage dispense unit according to claim 3 or claim 4, in which the spigot is associated with a screw-threaded member for axial movement.

6. A beverage dispense unit according to any preceding claim, in which the adjustable flow control means is manually adjustable.

7. A beverage dispense according to any preceding claim, in which the adjustable flow control means comprises a member provided on a dispense nozzle of the unit.

8. A beverage dispense unit according to claim 7, in which the member is at the bottom end of the nozzle.

9. A beverage dispense unit according to any preceding claim which has an orifice plate which defines the flow hole of the variable flow path means.

10. A beverage dispense unit according to any preceding claim, in which the flow hole of the variable flow path means is of much larger size than the fixed flow holes of the fixed flow path means.

11. A beverage dispense unit according to claim 10, in which the fixed flow holes have a diameter in the range 0.6mm to 1.lmm and in which there are about five fixed flow holes.

12. A beverage dispense unit according to any preceding claim which has an orifice plate and which has spring biasing means to bias the orifice plate against a seating.

13. A beverage dispense unit according to any preceding claim, in which the unit comprises a member, such as a nozzle, having a bore in which is provided an orifice plate and the adjustable flow control means.

14. A beverage dispense unit as claimed in any preceding claim, in which an expansion chamber is provided downstream of the fixed flow path means.

15. A beverage dispense unit according to claim 14 in which the expansion chamber is adapted to increase in volume as the variable flow path means is opened to increase the flow through the variable flow means.

16. A beverage dispense unit according to claim 15 in which a movable member is provided, said movable member defining in part the expansion chamber and also having provided associated with it one of a hole or valve member of the variable flow means.

17. A beverage dispense unit according to any preceding claim in which a nozzle body is provided to dispense a beverage, and in which the variable flow path means includes a movable member and in which a flow passageway is defined between the movable member and the nozzle body.

18. A beverage dispense unit according to claim 16 or 17 in which a flow passageway is defined inside a movable member.

19. A beverage dispense unit as claimed in any one of claims 16 to 18 which is provided with a nozzle body, and in which the movable member is not detachable from the nozzle.

20. A method of controlling the foaming of beverage when it is dispensed comprising providing one or more fixed dispense orifices or passageways, providing variable dispense means and adjusting the variable dispense means, the overall foaming of the beer being influenced by the fixed dispense orifices as modified by the effect of the variable dispense means.

21. A method according to claim 20, which comprises reducing or increasing the pressure drop across the fixed dispense orifices by adjusting the variable dispense means.

22. A method according to claim 20 or claim 21 which comprises manipulating manually operable adjustment means.

23. A method according to claim 22 which comprises turning manually operable adjustment means through 360C or less for the full range of flow variation.

24. A method according to any of claims 20 to 23 in which the adjustment means is infinitely variable, or substantially so, within limits, and the user adjusts the variable flow to achieve the desired foaming.

25. A method of compensating for variations in temperature, pressure, and gas content of a beverage as it is delivered, the method comprising providing both fixed and variable orifices, and varying the (or each) variable orifice(s) within a predetermined range.

26. A beverage dispense unit substantially as described herein with reference to Figures 3 to 8 of the accompanying drawings.

27. A method of controlling the foaming of a beverage when it is dispensed substantially as described herein with reference to Figures 3 to 8 of the accompanying drawings.

28. A method of compensating for variations in temperature, pressure, and gas content of a beverage as it is delivered substantially as described herein with reference to Figures 3 to 8 of the accompanying drawings.