Beverage chiller

The present invention provides an improved beverage chiller comprising at least two interconnected canisters each canister defining a chamber for refrigerant. The chamber includes a plurality of pipes extending along the length of the chamber for the flow of beverage thereghrough. Each canister includes flow control means to ensure flow of beverage up and down the refrigerant chamber in a plurality of cooling passes. The refrigerant chambers are pressure balanced and arranged to be coupled to a source of refrigeration via a thermostatic expansion valve.

FIELD OF THE INVENTION 
The present invention relates to beverage chillers. 
There is a need to chill carbonated and non-carbonated bulk beverages such 
as, for example, beer and wine. In some situations there is a requirement 
to produce a constant flow of chilled beverage at a temperature of as low 
as 2 to 3.degree. C. at a flow rate of up to 50 litres per hour. These 
parameters place demanding requiremrents on suitable equipment. 
One known technique for chilling bulk beverages is to pass the beverage 
through a continually refrigerated ice bag. However this technique suffers 
from a limitation on the flow rate which can be achieved whilst 
maintaining the desired chilled temperatures. 
Another known beverage chiller is a product known as TEMPRlTE. In this 
product, the beverage passes through a single spiral coil that is immersed 
in refrigerant. In order to ensure a constant level of refrigerant this 
product uses a float in conjunction with a cartridge valve. However a 
shortcoming with this equipment is that it requires frequent ongoing 
maintenance with the ensuing cost associated with servicing. For example, 
the float and cartridge valve control utilised in the product is prone to 
sticking in an open position or leaking after a period of use. If such 
conditions are left unchecked, flooding of the refrigerant into the 
compressor can occur and can lead to compressor failure. 
Such problems have brought about the present invention. 
SUMMARY OF THE INVENTION 
According to the present invention, there is provided a beverage chiller 
comprising at least two interconnected canisters, each canister defining a 
chamber for refrigerant, said chamber including a plurality of pipes 
extending along the length of the chamber for the flow of beverage 
therethrough, each canister including flow control means to ensure flow of 
beverage up and down the refrigerant chamber in a plurality of cooling 
passes, said refrigerant chambers being pressure balanced and arranged to 
be coupled to a source of refrigeration via a thermostatic expansion 
valve. 
Preferably the canisters are interconnected such that the beverage 
completes its cooling passes in one canister before completing further 
cooling passes in the second canister. 
Preferably a flow control means is provided at each end of each canister to 
ensure flow of beverage up and down the refrigerant chamber in a plurality 
of cooling passes. It is further preferable that the flow control means 
comprises a partitioned plate provided at each end of each canister. 
It is further preferable that each of the chambers is coupled to a source 
of refrigerant and an evaporator pressure regulator valve. 
Preferably the refrigerant chambers of the canisters are interconnected at 
three points along the length of the canister where a first connection is 
a suction connection that is in turn coupled to a compressor of a 
refrigeration circuit, a second connection is a balancing pipe that 
ensures pressure balance between said canisters, and a third connection is 
a thermal expansion valve feed connection. 
It is also preferable that the pipes of each chamber are arranged in an 
array which is parallel to the principal axis of the canister.

DISCUSSION OF THE PREFERRED EMBODIMENT 
The beverage chiller 10 illustrated in the accompanying drawings comprises 
two stainless steel canisters 11 and 12, of approximately 100 millimetres 
(.apprxeq.4 inches) in diameter and 350 millimetres (.apprxeq.13.5 inches) 
in length. Each canister 11, 12 preferably houses thirty two stainless 
steel pipes 20 of relatively small bore that are arranged in an array 
which is parallel to the principal axis of the canister. The pipes 20 are 
of 4.8 millimetres (3/16 inch) nominal bore and approximately 300 
millimetres (.apprxeq.12 inches) in length and are supported at either end 
by directional flow plates 21, 22. The directional flow plates 21, 22 are 
provided with thirty two small holes 23 and the ends of the pipes 20 are 
welded into these holes. The upper flow plate 21 has its upper surface 26 
segmented into five compartments 30, 31, 32, 33, 34 by upwardly projecting 
and radially extending baffles 27. The lower plate 22 has its lower 
surface 28 segmented into four compartments 35, 36, 37, 38 by radially 
extending baffles 29. Each plate 21, 22 is welded to the interior of the 
canister 11 or 12 at a position approximately 10 millimetres (.apprxeq.0.5 
inch) below the top and bottom of the canister. The canisters are closed 
and sealed at both ends 40, 41. Five segments 43 are individually welded 
to the upwardly projecting baffles 27 to seal the upper end 40 of each of 
the canisters, whilst four segments 44 are individually welded to the 
downwardly projecting baffles 29 to seal the lower end 41 of each of the 
canisters. 
The cavities 50 that house the pipes 20 between the directional flow plates 
21, 22 of the canisters contain refrigerant and are coupled to a standard 
refrigeration circuit which includes a source of refrigerant and an 
evaporator pressure regulator valve. It is understood that the design and 
operation of the refrigeration circuit would be well known to those 
skilled in this art and therefore it is not described in detail in this 
specification. 
As shown in FIG. 1, the refrigerant cavities 50 of canisters 11, 12 are 
interconnected at three points 53, 54, 56 along the length of the 
canisters. The upper connection 53 is a suction connection that is in turn 
coupled to the compressor of the refrigeration circuit. The central 
connection 54 is a balancing pipe that ensures pressure and refrigerant 
level balance between the canisters 11, 12. The lower connection 56 is a 
T.X. (Thermostatic Expansion) valve feed connection. The T.X. valve 
temperature control is located at a point approximately 300 millimetres 
(.apprxeq.12 inches) along on the upper connection 53 on the suction pipe 
to the compressor. 
The end segments 43, 44 are welded against the adjacent outer edges of the 
baffles 27, 29 to define segmented compartments 30 to 34 and 35 to 38 at 
each end of the canisters 11, 12. As shown in FIG. 2, one compartment 30 
at the top of each canister has an opening which constitutes the beverage 
inlet 61 and beverage outlet 62. The compartments 34 are interconnected by 
a bridge 65. 
In use the beverage to be chilled enters the first canister 11 via the 
inlet 61 into compartment 30. The beverage then flows down the four small 
bore pipes 20 contained in segment 30 to reach the compartment 35 defined 
by the lower directional flow plate 22. The beverage then flows up the 
four pipes to reach the upper compartment 31. It then flows down four 
pipes to reach compartment 36, back up to compartment 32, down to 
compartment 37, up to compartment 33, down to compartment 38 until it 
reaches upper compartment 34 from where it proceeds to the second canister 
12 via bridge 65 where the circulation operation is repeated. 
As the beverage passes through the chiller in each canister, it is passed 
through four single pipes concurrently and then returns to a separate set 
of four pipes that are all identical in size. Consequently, the beverage 
is passed through eight sets of four pipes in each canister. This lengthy 
and convoluted route for the beverage to pass is contained within the 
source of refrigerant which means that there is an enormous opportunity 
for heat exchange between the refrigerant and the beverage. Consequently, 
the beverage chiller has the capacity to chill beverages to the desired 
temperatures of 2 to 3.degree. C. whilst providing a flow rate of 50 
litres an hour. The design of the beverage chiller provides a heat 
exchanger of high efficiency which allows the performance criteria to be 
reached with a very compact unit that is very efficient in the use of 
power. 
This system is designed to operate on a variety of refrigerants and 
especially 134A or R12. 
Each canister is mounted with its axis vertical and filled to 75% of full 
capacity with refrigerant. The T.X. valve controls throughput of 
refrigerant whilst at the same time acting as a level control. A T.X. 
valve is a simpler and more efficient means of controlling refrigerant 
levels than the complicated float valve that is currently used. The 
beverage chiller can be incorporated into a refrigeration circuit or could 
be simply coupled to an existing refrigeration system. 
Overleaf are results of a test programme in which water was supplied into 
the beverage chiller at temperature of 17.5.degree. C. and a 10 oz glass 
was drawn off every 20 seconds for one hour. The temperature of each glass 
of water drawn off was noted as ranging from 0.7.degree. C. to 2.9.degree. 
C. at a delivery of 51.2 litres per hour (.apprxeq.11.25 gallons per 
hour). 
__________________________________________________________________________ 
.degree.C. 
.degree.C. 
.degree.C. 
.degree.C. 
.degree.C. 
.degree.C. 
No. 
Temp. 
No. 
Temp. 
No. 
Temp. 
No. 
Temp. 
No. 
Temp. 
No. 
Temp. 
__________________________________________________________________________ 
1. 0.8 31. 
2.3 61. 
1.8 91. 
1.6 121. 
1.7 151. 
1.7 
2. 0.7 32. 
2.3 62. 
1.8 92. 
1.7 122. 
1.6 152. 
1.7 
3. 0.8 33. 
2.3 63. 
1.8 93. 
1.6 123. 
1.6 153. 
1.6 
4. 1.1 34. 
2.2 64. 
1.8 94. 
1.6 124. 
1.6 154. 
1.7 
5. 1.6 35. 
2.2 65. 
1.8 95. 
1.8 125. 
1.7 155. 
1.7 
6. 1.8 2.3 1.8 1.6 1.6 1.7 
7. 2.0 2.3 1.8 1.6 1.7 1.7 
8. 2.1 2.3 1.8 1.6 1.7 1.7 
9. 2.1 2.3 1.8 1.6 1.7 1.7 
10. 
2.1 40. 
2.3 70. 
1.8 100. 
1.6 130. 
1.7 160. 
1.7 
2.1 2.3 1.9 1.6 1.6 1.7 
2.2 2.2 1.9 1.6 1.7 1.7 
2.3 2.2 1.9 1.6 1.7 1.7 
2.3 2.1 1.9 1.6 1.6 1.7 
2.3 2.0 1.9 1.5 1.8 1.7 
2.4 1.8 1.9 1.6 1.7 1.6 
2.4 1.8 1.9 1.7 1.7 1.7 
2.4 2.0 1.9 1.7 1.8 1.8 
2.5 2.0 1.9 1.6 1.7 1.7 
20. 
2.8 50. 
2.2 80. 
1.9 110. 
1.6 140. 
1.7 170. 
1.7 
2.5 2.1 2.0 1.6 1.7 1.7 
2.8 1.9 2.0 1.6 1.7 1.7 
2.7 1.9 2.0 1.6 1.7 1.8 
2.7 1.8 2.0 1.7 1.7 1.8 
2.8 1.7 2.1 1.6 1.8 1.7 
2.8 1.7 1.9 1.6 1.7 1.8 
2.9 1.7 1.8 1.6 1.7 1.8 
2.9 1.7 1.7 1.7 1.7 1.8 
2.6 1.7 1.7 1.7 1.7 1.7 
30. 
2.5 60. 
1.8 90. 
1.7 120. 
1.7 150. 
1.6 180. 
1.7 
__________________________________________________________________________ 
Supply Water at 17.5.degree. C. 
1 .times. 10 oz. Glass samples every 20 seconds for 1 hour. 
Total 180 Glasses (1800 fluid ounces) = 11.25 Gallons = 51.2 liters