GB2228310A

GB2228310A - A beverage cooling system

Info

Publication number: GB2228310A
Application number: GB9003369A
Authority: GB
Inventors: Christopher Michael Cook; Andrew Rigby
Original assignee: IMI Cornelius Inc
Current assignee: Cornelius Inc
Priority date: 1989-02-15
Filing date: 1990-02-14
Publication date: 1990-08-22
Anticipated expiration: 2010-02-14
Also published as: GB9003369D0; GB8903409D0; GB2228310B

Abstract

An insulated multi-beverage pipeline (python) cooling system incorporates a temperature sensor 14 to control the speed of a pump 8 and hence the flow of cooling water through the python 11 to prevent over or under cooling of the python. The speed of the pump may be controlled or varied automatically according to time. <IMAGE>

Description

Beverage Cooling System This invention relates to beverage cooling systems and has particular reference to beverage cooling systems used in connection with so-called python systems.

A python comprises a large diameter (10 cm) insulated plastics tube containing a plurality of beverage lines which are used to interconnect a series of beverage storage containers with a series of beverage dispense points. The python prevents the beverages, typically beer and lagers, from being over-heated in their passage from a temperature stabilised cellar to the beverage dispense point.

Typically, in a public house or other licensed premises, the beverage dispense lines pass through the bar area which can become very warm. Where the beverage is dispensed intermittently and in the absence of an insulated python the beer would become over-warm in the beverage lines.

Normally, the small diameter beverage lines are placed concentrically around a central, larger diameter, pipe through which cold water is pumped to maintain the product temperature. This water is recirculated via a chiller.

In order that the recirculation system can provide the initial lift for the water, a large pump is necessary to pump the water through the larger pipe and back to the water chiller. However, once the initial lift of water has been provided, a quantity of chilled water far in excess of the system's usual requirements continues to be pumped around the system.

Normally, the chilled water is obtained from a water bath containing an ice bank, the ice bank having been formed on an evaporator of a refrigeration system. The ice bank builds up during periods of low demand and is used to even out the refrigeration load requirement.

Unfortunately, with high water flow rates the excess of water slowly washes the ice bank, thus reducing the efficiency of the cooler unit.

Furthermore, the high flow rate of chilled water can over-chill the drinks in the python and the initial drinks served after the python has been standing for some while can be at too low a temperature.

By the present invention there is provided a beverage cooling system including a water bath, a refrigerator evaporator in the water bath, an insulating tube containing a plurality of beverage lines and a recirculating coolant line, a pump to pump water from the water bath through the recirculating coolant line and back into the water bath, characterised in that there is provided means to vary the output (ie the volumetric flow rate) of the pump so as to have at least two output volumes.

The output of the pump may be varied manually such that the output is reduced after the original lift of water has occurred. Alternatively, the output may be varied automatically such that after the initial lift has been achieved a timer operates to reduce the pump speed to a lower level.

In a further alternative, the pump output may be varied in response to variations of temperature of the interior of the insulating tube, or of the water returning from the insulating tube or reaching the distal end of the insulating tube, or of the temperature of the beverage passing through the beverage lines, preferably at or near the outlet of the beverage lines.

The output of the pump may be increased with an increase in sensed temperature.

The pump output may be varied by varying its speed. The pump is preferably driven by an electric motor, and the motor speed may be variable continuously or in discrete steps. The motor may be controlled by phase angle control. The pump may be a regenerative pump or a centrifugal pump. The output of the centrifugal pump may be varied by throttling the coolant in flow.

By way of example embodiments of the present invention will now be described with reference to the accompanying drawing which is a schematic view of a beverage cooling system in accordance with the present invention.

In the drawing, there is shown an insulated container 1 forming a water reservoir 2 for cooling water. An evaporator coil 3 forms an ice bank 4 in the water reservoir. A refrigeration system of conventional form including a compressor pump 5 to compress refrigerant, a condenser 6 and a fan 7 acts in the normal manner to provide a flow of refrigerant to the evaporator coil 3. The thickness of the ice bank 4 can be controlled by any suitable means.

A pump 8 draws water from the water reservoir 2 via a dip tube 9 and passes it through an outlet pipe 10 into an insulating tube 11 which forms part of a python system. A plurality of beverage lines passes through the insulating tube. The beverage lines are not shown in the drawing but are of a conventional form. The python 11 is also of conventional form and the chilled water is recirculated through loop 12 and back via line 13 into the water reservoir 2. 9 temperature sensor 14 senses the return temperature of water emerging from the python 11 and controls the speed of pump 8 via control box 15. The sensor may be located on a product line under the insulation.

When the system is switched on initially, the water in the line 13 will be warm. This will be sensed by sensor 14 and the control box 15 will operate pump 8 at its maximum speed. As the water circulating through python 11 chills the beverage in the lines within the python, the return water temperature falls and this is sensed by sensor 14.

With the fall in the temperature, control box 15 reduces the speed of pump 8. This reduction causes a reduction in the power requirement of the system, a reduction in the noise of the system, a reduction in the excessive water flow over the ice bank 4 and also reduces the wear on pump 8 and its drive motor.

Controlling the speed of pump 8 thus has a number of significant advantages compared to existing systems. The noise levels are lower, the wear on the pump is lower, and the power requirement for the pump - and hence the electrical costs are lower. There is also a hidden benefit, in that the refrigeration costs are lowered. By reducing overcooling, the amount of chilled water required for recirculation is lowered, and hence the refrigeration load is lowered. There is thus a double power saving.

The pump 8 may be a centrifugal pump, but is preferably a regenerative pump. It is driven by an electric motor - typically a horsepower AC induction motor rated 180 W. Control may be by phase angle control or by chopping the wave form. An electronic control circuit can be used to chop the form of the AC wave for power control purposes. If a centrifugal pump is used, the power output can be controlled by throttling the coolant inflow, which will reduce output and electric motor load.

Claims

CLAIMS:

1. A beverage cooling system including a water bath, a refrigerator evaporator in the water bath, an insulating tube containing a plurality of beverage lines and a recirculating coolant line, and a pump adapted to pump water from the water bath through the recirculating coolant line and back to the water bath, characterised in that there is provided means to vary the output of the pump so that at least two different outputs can be provided.

2. A beverage cooling system as claimed in Claim 1 in which means are provided for determining variations in the temperature of the water returning from the insulating tube, and that control means is provided to vary the pump output in response to variations in said temperature.

3. A beverage cooling system as claimed in Claim 1 in which means is provided for determining variations of temperature in the water reaching the distal end of the insulating tube and that control means is provided to vary the pump output in response to variations in said temperature.

4. A beverage cooling system as claimed in Claim 1 in which means is provided for determining variations in the temperature of å beverage passing through a beverage line which in turn passes through the insulating tube, and that control means is provided to vary the pump output in response to variations in said temperature.

5. A beverage cooling system as claimed in any of Claims 2 to 4 in which the output of the pump is adapted to be increased with an increase in sensed temperature.

6. A beverage cooling system as claimed in any preceding claim in which the pump output is adapted to be varied by means for varying the speed of an electric motor driving said pump.

7. A beverage cooling system as claimed in Claim 6 in which the motor is controlled by a phase angled controller.

8. A beverage cooling system as claimed in any preceding claim in which the pump is a regenerative pump.

9. A beverage cooling system as claimed in any preceding claim in which means is provided to reduce the output of the pump after an initial interval following start up when the pump operates at a higher output.