GB2090920A

GB2090920A - Pressurised beverage dispensing

Info

Publication number: GB2090920A
Application number: GB8200416A
Authority: GB
Original assignee: Grundy Teddington Ltd
Current assignee: Alumasc Grundy Ltd
Priority date: 1981-01-08
Filing date: 1982-01-07
Publication date: 1982-07-21
Also published as: GB2090920B

Abstract

A beverage dispensing system having supply keg 1 pressurised by gas 2 includes a volummetric metering unit 4 and a bar tap 6 supplied with a measured quantity of beverage through line 5. To avoid fob forming throughout the length of line 5 following supply, the line is repressurised using a heating means 11, such as a PTC thermistor, in the valve 9. This causes intensive localised fobbing at the valve to pressurise line 5, the fob being ejected at the next dispense cycle. <IMAGE>

Description

SPECIFICATION Pressurised beverage dispensing This invention relates to pressurised beverage dispensing and more particularly is concerned with an arrangement to reduce or avoid fobbing within the beverage dispense line leading to the dispensing tap or valve.

When dispensing beverages through a volumetric metering unit disadvantageous effects occur between the metering unit and the dispense tap valve at the bar. During the dispensing cycle the beverage output line is subject to a pressure differential between atmospheric pressure at the tap end and full line pressure at the metering unit. When the metering unit has discharged the required quantity of beverage the line is closed at the meter outlet but the line from the meter to the tap reduces to atmospheric pressure. Thus when the tap is closed, for example by means of the customary solenoid valve, beverage at atmospheric pressure is trapped in the section of line between the metering unit and the tap. As the beverage in this portion of the line warms up then carbon dioxide gas breaks out of solution and a fob forms along the entire length of the line.Arrangements are known to prevent this occurring and this can be achieved either by chilling the section of line to a very low temperature or by artificially re-pressurising the line following the dispense operation. Hitherto, re-pressurisation has been achieved through by-passing the metering unit when the tap is closed, but this causes a slight error in the volume of beverage dispensed as some of the beverage does not then pass through the meter unit on its way to the dispense point tap.

It is an object of this invention to provide an easily embodied means whereby the line may be re-pressurised following dispensing without producing the aforementioned error in the quantity of beverage discharged.

According to this invention in a system for dispensing a pre-determined volume of beverage using a metering unit preceding a dispense point tap, there is provided within the dispense point tap valve unit a heating means to supply a controlled quantity of heat to the liquid duct at the valve thereby to cause carbon dioxide to break out of solution at the valve to effect re-pressurisation of the line connecting the valve with the metering unit.

The heating means may be a resistive element which is controlled thermostatically or by a regulating device or circuit with a sensing means but advantageously the heating is effected by means of a positive temperature co-efficient thermistor which is positioned within the valve and connected to a voltage supply which conveniently is the low voltage a.c. supply normally present for operation of the valve or supply of bar illumination lamp units. This preferred embodiment is particularly advantageous in so far as the temperature is controlled whilst the thermistor is permanently connected to the electric supply. The carbon dioxide fob which forms at the valve is expelled when the tap is initially opened to begin the next dispense cycle.

The invention is further described and illustrated in conjunction with the accompanying drawings showing an embodiment by way of example.

In the drawings: Figure 1 shows a system for dispensing metered quantities of beverage, and Figure 2 shows a detail of a solenoid tap valve unit.

Referring to Figure 1, a system for dispensing metered quantities of beverage is generally of conventional form employing a pressurised container 1 for the bulk supply of a beverage with an associated carbon dioxide gas pressurising source 2. Pressurised beverage passes through line 3 into a cooling and metering unit 4 which employs valve means to ensure that precisely determined volume of beverage is dispensed at each cycle through the outlet line 5 connecting the meter 4 with the dispense tap unit 6.The dispense tap unit 6 will generally form an integrally operative part of the meter and includes a press switch 7 which initiates dispensing of the measured volume of beverage by sending an appropriate signal to the meter unit 4 via line 8 and causing a solenoid operated tap valve 9 to open thereby permitting beverage to flow out through the tap nozzle 1 0. The beverage continues to flow until the meter unit has dispensed the predetermined volume whereupon the meter unit valve closes together with the solenoid valve 9.

At this point beverage within the pipe 5 normally warms up thus causing carbon dioxide to break out of solution and severe fobbing then occurs in the pipe 5. In order to avoid this disadvantage and according to a preferred feature of this invention, the solenoid tap valve 9 incorporates therein a heating means 11 comprising a positive temperature co-efficient thermistor and this is supplied with 24 volts a.c.

The thermistor produces a controlled amount of heat which passes to the bar valve and the warming of the valve which occurs produces localised carbon dioxide fob which has the effect of re-pressurising the entire line 5.

As soon as the solenoid tap opens to discharge the next measured volume of beverage the volume of fob is harmlessly expelled from the outlet 10.

Figure 2 shows in longitudinally exploded view a construction of solenoid valve 9 comprising coil 20 which is energized through connections 21 in order to open the valve and having an armature 22 with a movable valve member 23 serving to close or open the valve formed by a seat within the body 4. The armature 22 incorporates a positive temperature co-efficient thermistor coupled via leads 25 to a suitable electrical supply. By virtue of the temperature co-efficient of the thermistor electrical supply thereto may be continuous, the arrangement providing a self control of the heat output to the valve.

Claims

1. In a system for dispensing a pre-determined volume of beverage using a metering unit preceding a dispense point tap, the provision within the dispense point tap valve unit of a heating means to supply a controlled quantity of heat to the liquid duct at the valve thereby to cause carbon dioxide to break out of solution at the valve to effect re-pressurisation of the line connecting the valve with the metering unit

2. A beverage dispense tap including an electric heating means located within the tap valve and arranged to supply heat to liquid in the valve.

3. A system or dispense tap according to Claim 1 or 2, wherein the heating means is a resistive element which is controlled thermostatically or by a regulating device or circuit with a sensing means.

4. A system or dispense tap according to Claim 1 or 2, wherein the heating means is a positive temperature co-efficient thermistor which is positioned within the valve and connected to a voltage supply.

5. A system or dispense tap according to Claim 3 or 4, wherein the valve is solenoid operated, the solenoid armature including the thermistor or resistive element.

6. A beverage dispensing system substantially as described herein and with reference to or as shown in the accompanying drawings.

7. A beverage dispense tap substantially as herein described with reference to either Figure 1 or Figure 2 of the accompanying drawings.