IE61043B1 - Apparatus and method for dispensing cooled liquids - Google Patents

Abstract

A cooling system (flow flex) for multiple dispense point beer or beverage systems in which the beverage is cooled immediately prior to dispense by passage through a heat exchanger 15 and in which a coolant is also passed through the heat exchanger 15 from a central source comprising bath 5, the arrangement being such that the tap 27 which controls flow of beverage to the dispense point also controls the flow of cooling water through the heat exchanger 15 to prevent excess chilling of the beverage when no beverage is being dispensed. Optionally, there may be provided a trickle of coolant through the heat exchanger to keep the beverage chilled during rest periods.

Description

This invention relates to liquid coolers and has particular, but not exclusive, reference to beer coolers. There are two principal forms of beer coolers in present production, the first is a shelf cooler and the second is a remote cooler. With a shelf cooler there is provided a heat exchanger located directly below the bar incorporating its own refrigeration system and the refrigeration system passes heat from the beer into the area below the bar.

Shelf coolers are simple portable units which have good temperature control and are able to cool the beer close to the dispense point,. They do have the disadvantage however of taking up valuable space below the bar and they are expensive when many are required for a large public house. Furthermore, putting heat into the working area of the bar is a disadvantage, particularly in hot nights during the summer, and the units tend to be noisy and operate in dirty, sticky areas which result in the condensers becoming easily blocked.

The second type of beer cooler is a remote cooler which is normally provided in a cellar where there is more space and which is intended to cool a number of beer lines. Noise is not a problem because the cooling unit is remote from the bar. The unit is economical in that one large cooler may suit many beers and the heat is generated away from the bar area. There are disadvantages however, in that a remote cooler cools all beers and lagers to a similar temperature and there is no choice of temperature at the tap. The unit requires a cold water recirculation line from the cellar to the bar to keep the beers cool in the passage from the cellar to the bar. Γ According to one aspect of the invention, we ζ provide apparatus for dispensing cooled liquid such as beer or lager comprising means for supplying a liquid from a store eg a keg to a dispense point eg, a tap, said store being remote from said dispense point, a liquid cooler at or adjacent the dispense point, said liquid cooler comprising a heat exchanger to exchange heat between the liquid and a cooled fluid, and control means for permitting full flow of said cooled fluid into said heat exchanger only in response to the initiation of opening or the opening of the dispense point- Said control means preferably also includes means for reducing or stopping the flow of cooled fluid into said heat exchanger in response to the initiation of closure or the closure of the dispense point.

The cooled fluid, typically water, may be carried in a feed line fx*om a fluid cooler remote from the dispense point, which line passes adjacent a plurality of the said dispense points. Each dispense point may have its own liquid cooler ox- alternatively each pair or trio of dispense points may have a single liquid cooler. In the alternate case, cooled fluid is drawn into the heat exchanger in response to the actuation of opening or the opening of any of the pair or trio of dispense points. The liquid coolers or their associated connections to the feed line may differ according to the type of liquid to toe cooled. It may be desirable to dispense one type of liquid (eg lager) at a lower temperature than another (eg beer). Liquid coolers associated with higher temperature dispense may have a lower heat exchange effective surface area than those for lower temperature dispense. Alternatively, they may have means which permits a lower volume rate throughput of cooled fluid than for the lower temperature dispense liquid, coolers.

A common return line may run parallel to the common feed line for cooled fluid. Fluid passing through the heat exchanger of each liquid cooler is returned to the fluid cooler via this return line. There may be a pressure responsive valve at the end of the cooled fluid feed line {ie after passing the plurality of dispense points) which opens above a predetermined pressure value to pass cooled fluid to the return line, and thence to the fluid cooler. Alternatively, there may be a temperature-responsive valve between said feed and return lines to permit a proportion of the fluid feed to be recirculated via the return line to the fluid cooler in the event that the fluid temperature in the fluid feed at a particular point rises above a predetermined value.

The cooled fluid may be passed into the heat exchanger of a liquid cooler prior to the opening of the dispense point. This may be done by having a time delay between the initiation of opening eg the pressing of a button, and the opening which permits cooled liquid to flow from the dispense point. r The cooled fluid may be permitted to trickle (' flow at a low rate through the liquid cooler during the time when full flow is prevented by the control means.

Bv wav of example embodiments of the present invention will now be described with reference to the accompanying drawings of which FIGURE 1 is a schematic view of a system in accordance with the present invention, and FIGURE 2 is a schematic part sectional view of a cooling module in accordance with the present invention.

Referring to Figure 1, this shows a system in accordance with the invention for. dispensing beer from a keg 1 into a glass 2. The beer is cooled within a module generally indicated by 3» Cooling water for the module is provided from a remote cooler unit generally indicated by 4. In the remote cooler unit there is provided a bath 5 of water chilled in a conventional manner by an evaporator coil 6. The refrigeration unit incorporates a compressor 7 and an evaporator 8. The evaporator may toe so arranged as to pump hot air to the outside of a building containing th® system. An ice bank 9 builds up on the evaporator 6 to keep the water in the bath 5 close to 0 °C.

Chilled water is withdrawn from th© bottom of the bath 5 via a pump 10 operated toy an electric motor t 11. The chilled water is passed from the pump into a line 12. The line 12 feeds a series of modules such I as module 3 and there is a return line 13 which returns used or warmed water from the modules to the bath 5.

At th© end of the line 12 there is provided a pressure release or toy-pass valve 14 which maintains a Ί ) pressure on the line 12 and which permits the flow or by-pass of water through lines 12 and 13 when no beer is being cooled by any of the modules 3«, Considering now in more detail the modules, such as module 3, there is provided a plate heat exchanger 15 having an inlet 15 for chilled water which is connected by line 17 to the main supply 12.

Water from the plate heat exchanger 15 passes out from exit 50 through line 18 to a valve 19. From valve 19 water returns via line 20 to the main return line 13» Beer from keg 1 passes under the action of pressure supplied by a CO2 line 21 through line 22 to the valve 19. From valve 19 the beer passes via line 23 to inlet 24 for the heat exchanger 15 and thence from exit 25 via line 26 to the glass 2» It can be seen that valve 19 controls both the supply of beer and the supply of cooling liquid- The reason for this is that by controlling single handle 27 both the beer line and the cold water line can be opened so as to permit both beer and cold water to flow through the heat exchanger.

Because the temperature of the cold water entering the plate heat exchanger 15 is always substantially constant and because the beer in line 22 will always have a substantially constant temperature,» the temperature of the beer emerging from line 26 will be dependant on the cooling effect of the plate heat exchanger.

One of the characteristics of a plat® type cooler is the consistency of heat exchange within the unit such that with constant input temperatures the draw off rate of the beer is not a factor effecting the temperature of dispense. Thus, the beer dispense temperature will be the same irrespective of whether J5 litre or 2 litres per minute of beer is drawn r through the system.

The flow of chilled water passing through the imodule should be about 5 litres per minute to give a suitable rate of cooling. In a bath with 15-20 dispense points, this would imply the need of some 100 litres per minute of chilled water flow. It has to be recognised that this is a very high water flow and would need a pipe of approximately 5 cm diameter bore to carry the flow without excessive resistance.

As each of the flow and return pipes need to be 5 cm in diameter, they would be in such a circumstance difficult to plumb around and under the various bar installations.

Statistically however, in a bar with 15-20 taps, if is unlikely that more than half this number would be open at the same time. The dispense rate for beer and lager is usually some 20-25 seconds per litre. Thus, even at 1 litre per minute of the tap, it would still be closed for sense 50% of its time even at peak periods. The normal throughput per tap is further limited by both the time to dispense the beer,, the handling of change at the till, collecting clean glasses, taking orders, etc.

Thus, it can be seen that even if each tap needs a flow of 5 litres per module for cooling, a flow of some 35 litres per minute would cope with all 15-20 taps in view of the selective opening of each tap. t· It will be appreciated that at the heart or the module is the combination of the plate heat exchanger and the operating valve.

Referring to Figure 2, this shows the module attached to a bar 28 by means of a turn buckle 29 attached to the module generally indicated by 3» Cooling water for the plate heat exchanger 15 enters via line 17 and the rate of flow of cooling water through the plate heat exchanger can be controlled by regulating tap 29.

Beer enters the module through inlet line 22 and the ecolao beer passes out of the module through line 26 into the tap control 19. Similarly the flow of water from the plate heat exchanger 15 enters into the tap control 19 via line 18 and water from the tap 19 returns through line 20 into the return line 13.

The tap 19 is a simple flow control tap . operated by handle 27 and is so arranged that both the beer line and the cooling water line are controlled at the same time by the action of the single tap handle 27.

As far as the bar person is concerned, there is no difference between operating handle 27 to control both the beer and water lines, and a conventional beer tap which operates on the beer line only. It has been found in practice that most breweries cool the beer in the cellar so that the storage temperature of the beer emerging from the cellar is about 12 *C. With water in the tank 5 at 1 °c and the water passing through lines 12 having a temperature of about 2-3 “C it has been found that the use of a plate type cooling module of about 20 cm by 8 cm by 3 cm provides for a very efficient cooling system. The optimum benefit in cooling is obtained with a flow rate of about 4-5 litres per minute, but even at 2 litres per minute, cooling is very satisfactory. 3y using a flow rate from the pvaap 10 of about 30 to 35 litres per minute, the main flow lines 12 and 13 can have a diameter of about 2 cm and these therefore may be either flexible or rigid. Furthermore, the tubes connecting the modules to the main flow and return lines ie tubes 17, 20 can be even smaller, say 1 cm diameter. It will be appreciated that numerous modules similar to module 3 may be interconnected as shown at 30 and 40 in Figure 1, where module 30 is shown in slightly less detail than module 3 and module 40 is shown only schematically.

It will further be appreciated that one of the advantages of the system illustrated in Figures 1 and 2 is that it is an entirely mechanical arrangement. However, there may be occasions when, electrical interconnections between the two flow controls, ie the beer control and the cooling water control, are desirable. The present invention envisages such a system.

It may further be advantageous to provide a small bleed for cooling water through the plate heat exchanger 15 so that a small amount of cooling of the beer within the plate heat exchanger is occasioned even when the tap is not opened. Such a system prevents a build up of warm beer in the heat exchanger which might adversely effect the first half litre drawn during the opening of the public house.

It will b® appreciated that there are numerous advantages to the system of the present invention 1. it keeps all heat away from the bar 2. it uses known refrigeration system technology 3. there is very accurate dispense temperatures at the tap 4,, . 6. 7. 8. 9.

. XI. 12. 13. 14. individual temperature control of each product is possible by use of a simple flow regulator either on the module or at the tap the system does not overcool the occasional half litre taut is still able to cope with a high throughput very little space is utilised underneath the bar the system is easy to install and maintain and in the mechanical system no electrical installation is needed the system is robust, of simple design and hence good reliability as there ©re only three moving parts a) tap, b) flow regulator, and c) pressure bypass valve.

Items b and c are known parts and item a can be based on existing technology the system is cost effective the system is very flexible and can easily by extended or modified the system is suitable for all products, beer, lager, ale, soft drinks the system is hygenic and can be cleaned by existing processes the system can be retrofitted into existing bar installations easily and be used with existing remote coolers in cellars with the simple provision of a new pump the system requires a water pump of only modest duty. There is a low power consumption and a low capital cost.

Claims (12)

1. CLAIMS: /

1. Apparatus for dispensing cooled liquid such as beer or lager comprising means for supplying a liquid from a store to a dispense point, the store being remote from the dispense point, a liquid cooler at or adjacent the dispense point, the liquid cooler comprising a heat exchanger to exchange heat between the liquid and a cooled fluid, and control means for permitting full flow of the cooled fluid into the heat exchanger only in response to the initiation of opening or the opening of the dispense point.

2. Apparatus as claimed in Claim 1 in which the control means also includes means for reducing or stopping the flow of cooled fluid into the heat exchanger in response to the initiation of closure or the closure of the dispense point.

3. Apparatus as claimed in Claim 1 or 2 in which the cooled fluid is carried in a feed line from a fluid cooler remote from the dispense point and in which the feed line passes adjacent a plurality of the said dispense points.

4. Apparatus as claimed in Claim 3 in which each dispense point has its own heat exchanger.

5. Apparatus as claimed in any one of Claims 1 to 4 in which cooled fluid is permitted to trickle flow through the heat exchanger when the full flow is closed ,.,

6. Apparatus as claimed in any one of Claims 1 to r 5 in which the cooled liquid and the liquid to be cooled are both controlled by mechanical valves. C

7. Apparatus as claimed in Claim 6 in which th® mechanical valves are physically adjacent on© another.

8. » Apparatus as claimed in any one of Claims 1 to 5 in which the liquid to be cooled and the cooling fluid are controlled by electrically operated valves V · * or a combination of mechanical and electrically operated valves.

9. Apparatus as claimed in any one of Claims 3 to 5 8 in which there is provided a common feed line for the coolant liquid from a reservoir to the individual heat exchangers and a common return.

10. Apparatus as claimed m Claim 9 in which there is provided a bypass valve to interconnect the common 10 feed and return lines to maintain a pressure in the common feed and return lines and to act as a cooled liquid bypass when no liquid is cooled by any of the heat exchangers.

11. Apparatus for dispensing cooled liquid

12. 15 substantially as herein described with reference to and as illustrated by Figures 1 and 2 of the accompanying drawings.