GB2129775A - Apparatus for use in dispensing beer - Google Patents

Abstract

One kind of apparatus for dispensing beer comprises a pump (6) which is operative to draw beer from a container and discharge it from a dispense head (11). The invention provides an air inlet (15) upstream of the pump so that in use air is sucked into the beer flowing from the container to the pump. The nitrogen in the air improves the quality of the head on the beer dispensed. The pump may be manually operated and the air inlet may be an adjustable needle valve. There may be a non- return valve upstream of the air inlet to prevent the gradual return to the container of beer that has previously been drawn from the container towards the pump. When the dispense head includes a sparkler this assists the formation of an improved head. <IMAGE>

Description

SPECIFICATION Apparatus for use in dispensing beer This invention relates to apparatus for use in dispensing beer, the term beer being used herein in a broad sense to denote any alcoholic beverage made by fermenting hopped wort. More particularly the invention is concerned with apparatus for use in dispensing beer and of the kind (hereinafter referred to as the kind specified) comprising pump means operative to draw beer from a container and to cause it to be discharged from a dispense head.

Apparatus of the kind specified is normally used for dispensing beer from a container in which the beer is held at atmospheric pressure, with the consequence that in use the pump means sucks the beer up from the container, the beer passing through a supply duct from the container to the pump means.

The pressure of the beer flowing along the supply duct during dispense is therefore less than atmospheric pressure. The types of beer that are stored in containers at atmospheric pressure are necessarily beers in which there is not a high concentration of carbon dioxide, for beers with a high concentration of carbon dioxide, have to be stored at pressures greater than atmospheric pressure. In consequence of the relatively low concentration of carbon dioxide in the beer, the beer does not normally have a particularly good head when it is dispensed.

With a view to improving the head it is known to dispense the beer through a sparkler, that is a device which agitates the beer and breaks up the steady stream of beer so as to encourage it to froth.

However the resultant head tends not to be particularly stable.

In a known procedure for dispensing beer using apparatus of the kind specified, the beer is forced through a sparkler that is so adjusted as to give rise to a lot of froth. This is fed into a glass but is allowed to overflow. The overflowing froth falls into a trough or similar collector beneath the dispense head and is fed back into the beer to be pumped to the dispense head. This arrangement is referred to in the trade as an "autoback" or an "economiser". When such an arrangement is used, the overflowing beer is thus recycled, and as it is recycled air is entrained with it.

Now some four fifths of air is nitrogen gas, and it is known that the introduction of nitrogen gas into beer tends to improve the head on the beer when it is dispensed. It is therefore believed that the use of this recycling procedure in which air, and thus nitrogen, is entrained with the beer tends to improve the head of the beer finally dispensed. This procedure is, however, messy to carry out and can readily become unhygienic. For this reason its use is strongly discouraged.

An aim of the preent invention is to provide an improved form of beer dispensing apparatus capable of dispensing beer with an improved head but without any recycling of the beer through the apparatus.

According to the present invention there is provided apparatus, for use in dispensing beer, of the kind specified, characterised in that an air inlet is provided upstream of the pump means, the arrangement being such that when the apparatus is in use air is sucked into the beer flowing from the container to the pump means and is discharged with the beer from the dispense head.

The air inlet is preferably disposed close to the inlet of the pump means. The air inlet is preferably adjustable so that the proportion of air in the beer being dispensed can be varied as desired. A convenient form of air inlet is an adjustable needle valve. If desired the air inlet may incorporate a throat through which the beer has to pass on its way to the cylinder, air, in use, being drawn into the throat by a venturi action.

The pump means preferably comprises a manually reciprocable piston in a cylinder, but it could be of some other kind, such as an electrically driven rotary pump.

When the apparatus is not in use, beer upstream of the air inlet tends gradually to flow in the reverse direction under the influence of gravity, and to draw air through the air inlet and into the supply duct. To prevent or at least to reduce that effect it is preferred to provide a non-return valve upstream ofthe air inlet. This non-return valve is preferably adjacent to the air inlet but that is not essential and it may be near the beer container if desired.

Use of the invention tends to result in beer being dispensed with a head of improved stability so that it has a longer life than the head on-beer dispensed by means of conventional apparatus of the kind specified (with no recycling); the head may also have finer bubbles and be of a more creamy appearance than the head on beer dispensed by means of that conventional apparatus.

In order to ensure that the beer is suitably agitated and broken up as it is dispensed, the dispense head preferably includes a sparkler. This sparkler is preferably of the kind comprising a plate formed with perforations through which the beer is constrained to pass. The use of an effective sparkler, however, tends to result in the beer being discharged from the dispenser in an uncontrolled manner. It is therefore preferred to use a "straightener" which is operative to guide the beer into a more uniform stream after it leaves the sparkler. The "straightener" may comprise a fluted insert. In addition, or alternatively, there is preferably a short length of tube through which the beer is guided after passing through the sparkler, and after passing through the "straightener" where such is provided.

An example of apparatus embodying the present invention is illustrated in the accompanying drawing, which is a side view of the apparatus.

Much of the apparatus illustrated is constituted by a beer engine of a known kind. The beer engine has a base 1, which in use stands on a bar counter (not shown); a bracket 2 depends from one edge of the base and carries an arm 3 which in use extends beneath the bar counter. A screw clamp 4 mounted on the arm can be tightened to secure the base 1 to the bar counter. A downward extension of the bracket 2 also carries a spill-tray 5.

The beer engine also includes a pump comprising a cylinder 6 with a piston which can be reciprocated in the cylinder by means of piston rod 7. An operating handle 8 is mounted for angular movement relative to base 1 and is coupled to the piston rod 7 by means of a linkage 9. The cylinder 6 has an inlet at its lower end, provided with a non-return valve and an outlet at its upper end, the outlet being connected to an outlet pipe 10 terminating in a dispense head 11 which is disposed above the spill-tray 5. The vertical space between the dispense head 11 and spill-tray 5 is sufficient to enable a glass to be held between the dispense head, and the spill-tray.

The piston contains a one-way valve, the arrangement being in such that in use, when the operator pulls the operating handle 8 the piston is raised and the valve closes so as to cause beer above the piston in the cylinder 6 to pass through the outlet pipe 10 and to be discharged vertically downwards from the dispense head, more beer simultaneously being sucked into the cylinder, below the piston, through the inlet and the non-return valve. The return of the operating handle 8 to its initial, upright position (illustrated) causes the piston to be lowered in the cylinder with the result that the non-return valve at the inlet to the cylinder closes while the one-way valve in the piston opens and permits the beer in the cylinder to pass through the one-way valve, with the result that beer that was initially below the piston is finally situated above the piston.

The apparatus illustrated includes features additional to the features of a conventional kind of beer engine described above. Of these an important feature is the provision of an air inlet 12 comprising an adjustable needle valve disposed immediately upstream of the pump. A short length of pipe 13 is fitted between the inlet of the cylinder 6 and a flexible tube 14 constituting the principal part of a supply duct which in use leads to the inlet of the cylinder from a cask or other container which contains beer at atmospheric pressure and is disposed at a level below that of the beer engine. The length of pipe 13, which also constitutes part of the inlet duct, is formed with a lateral port which commmunicates with a chamber inside a cylinder body 15 of a needle valve mounted alongside the length of pipe 13.The body 15 has an open entrance for air at the top and includes an annular valve seat between the open top and the chamber inside the body. A needle with a tapered point at its upper end extends axially upwards through the chamber and enters a valve opening which is surrounded by the valve seat. The needle is mounted on screw means such that its axial position can be adjusted by rotation of a knurled knob 16 at the lower end of the body 15. Axial adjustment of the needle thus varies the extent to which the valve opening is obstructed.

A further non-return valve (not shown) is provided in the supply duct shortly upstream of the length of pipe 13.

The apparatus operates in the following manner.

Each time the operating handle 8 is pulled, the piston rises in the cylinder 6 and sucks beer up the supply duct and past the two non-return valves into that part of the cylinder below the piston. As beer passes through the length of pipe 13 its pressure is a little below atmospheric pressure. Air is therefore drawn into the beer from the chamber in the body 15, the rate at which air enters the length of pipe depending on the setting of the needle of the needle valve.

Simultaneously, beer that on a previous stroke was drawn into the cylinder and has reached a position above the piston, is discharged through the outlet pipe 10 and dispense head 11. As the handle 8 is returned to its initial, upright position the one-way valve in the piston opens, thus enabling the beer in the cylinder to pass through it. The non-return valve at the inlet to the cylinder closes, preventing beer returning back through the inlet. The other nonreturn valve, below the air inlet 12, also closes and thus prevents the beer in the tube 14 descending gravitationally and pulling air into the supply duct through the air inlet, a phenomenon that would gradually occur if no such non-return valve were provided.

The addition of the air to the beer adds additional gas to the beer; moreover a large proportion of that gas comprises nitrogen, which as explained above improves the nature of the head on the beer. A further advantage of the addition of the air is that it helps to break up the continuity of the liquid and thus to encourage the formation of bubbles in the beer.

In the dispense head 11 it would be possible to use a sparkler of the customary kind comprising an end cap having arcuate outlet slots formed around the base of an upwardly directed cone around which the beer is constrained to flow as it passes to those outlet slots. In a preferrred arrangement, however, (as illustrated) the dispense head 11 incorporates a sparkler in the form of a metal disc having a plurality of holes through which the beer is constrained to pass. Immediately downstream of the sparkler disc is a "straightener" formed as an insert of a plastics material and located at the entrance to a short length of pipe 17. At its upstream end the insert has an imperforate disc, the margin of which engages a flange in the head to restrain the insert against axial movement. Downstream of that disc is a longitudinally fluted body of cruciform cross-section.In use, beer passes through the perforate sparkler disc and is thus further boken up into a froth or foam. This then passes around the edge of the imperforate disc of the "straightener" and flows axially along the flutes. This prevents any swirling of the beer that might otherwise occur. The beer then flows along the short length of tube 17 and is discharged in a single coherent stream.

If the beer is discharged directly into a glass it is found that the great majority of the bubbles in the beer rise to the top quite rapidly and that a head is formed on the beer in the glass, this head normally having a structure of relatively small bubbles or cells and normally being relatively stable.

It is to be understood that numerous variations are possible without departing from the scope of the present invention. For example the needle valve may be replaced by some other form of air inlet, such as one incorporating a narrow throat, through which in use the beer passes, and an air duct leading to the throat, the device thus acting as a venturi to encourage the flow or air into the beer.

Claims (8)

1. Apparatus, for use in dispensing beer, of the kind specified, characterised in that an air inlet is provided upstream of the pump means, the arrangement being such that when the apparatus is in use air is sucked into the beer flowing from the container to the pump means and is discharged with the beer from the dispense head.

2. Apparatus according to claim 1 in which the air inlet is adjustable so that the proportion of air in the beer being dispensed can be varied as desired.

3. Apparatus according to claim 2 in which the air inlet comprises an adjustable needle valve.

4. Apparatus according to any one of the preceding claims in which the air inlet incorporates a throat through which the beer has to pass on its way to the cylinder, air, in use, being drawn into the throat by a venturi actioon.

5. Apparatus according to any one of the preceding claims in which the pump means comprises a manually reciprocable piston in a cylinder.

6. Apparatus according to any one of the preceding claims in which there is a non-return valve upstream of the air inlet.

7. Apparatus according to any one of the preceding claims in which the dispense head includes a sparkler.

8. Apparatus, for use in dispensing beer, of the kind specified, substantially as hereinbefore described with reference to the accompanying drawing.