IE44157B1 - Method and apparatus for producing and dispensing cooled carbonated water - Google Patents

Description

This invention relates to a method and apparatus for producing and dispensing carbonated water.

According to the invention, there is provided a method for producing and dispensing cooled water containing dissolved carbon dioxide gas, in which carbon dioxide gas is introduced directly into a pressurized store of cooled water which is divided by a surface cooled to a temperature below 0°Cy a forced flow is maintained in the water along one side of the cooled surface, and the carbon . dioxide gas is introduced under pressure through a finepored body into the flow in a finely divided form, and water is taken out of the store with a simultaneous release of pressure.

The invention also provides apparatus for producing and dispensing cooled carbonated water, comprising a pressure tight water container containing a cooling element which divides the water container, means for forcing the water to flow along one side of the cooling element, and a carbon dioxide gas introducing device with a porous body arranged to be below the water level and dose to the means for forcing the water to flow.

The invention will now be further described, by way of -1example with reference to the accompanying drawings in which:Figure 1 is a vertical section through a preferred embodiment of apparatus for the preparation and dispensing of carbonated water before start up; and Figure 2 is a view similar to Figure 1 of the apparatus during normal operation.

The water preparation device shown in Figures 1 and 2 consists of a pressure-tight tank 50, in which a water volume 52 is contained. The level of the water surface 53 in the tank 50 is controlled by a corresponding level detecting element 72 by way of a central control instrument, not shown. The control instrument controls a solenoid valve 66 through which water is fed under pressure through the line 67 into the head space 51 of the tank. The feed takes place under pressure in such a manner that the fed water creates no turbulence. For this purpose, the feed pipe 67 ends in an atomising head 68, which atomises the fed water, the mist or spray depositing on the water surface.

The low temperature of the water store 52, which is between 0° and 2°c, preferably a maximum of 1°C, is produced in the tank 50 by means of a refrigeration system. This is in the form of a helical evaporator coil 54, connected by its two connectors 55 and 56 to an external cold producer. -2The Figures show that the cylindrical evaporator coil 54, which extends over practically the complete height of the water store 52, divides the interior of the tank into two concentric zones, namely a zone 59 within the evaporator coil and an annular zone 58 outside the evaporator coil. The significance of this form will be discussed further hereinafter.

The interior of the tank 50 is under a predetermined pressure. This pressure is at the same pressure as the carbon dioxide gas, which is fed from a corresponding source through a solenoid control valve 69 to the water store 52. A feed pipe 70 is used for this purpose, which reaches into the water store close to the tank floor 60, its lower end being connected to a ceramic plug or other porous body 71, through which the carbon dioxide emerges into the water store 52 in very fine bubbles. This is an important prerequisite for fine impregnation of the water by carbon dioxide.

To prevent the accumulation of clouds of carbon dioxide bubbles, which could both detract from the quality of the soda-water and cause formation of larger bubbles and therewith a considerable loss of carbon dioxide in the water, a device is provided to compel practically laminar slow convective flow to take place in the tank. To this end a rotor 61 is supported at the deepest point in the -34415? floor 60 of the tank, drawing the water into its centre and throwing it outwards in a radial direction over the upward sloping floor. In the illustrated example, the drive is provided externally in a contact-free manner by an external rotatably supported magnet wheel 63, which is driven by the motor 62 and drags the rotor 61 magnetically.

The prepared water may be withdrawn through the line 64 by way of the solenoid control valve 65 and fed to the mixing zone.

When the tank is full and the cooling device in operation, an increasing ice layer forms in the region of the evaporator coil 54, first bridging the interspace between the neighbouring pipe turns, so that the evaporator coil 54 together with the forming ice in the tank forms in practice an approximately cylindrical separation wall, which separates the water volume within the evaporator coil 54 flow-wise from the water in the annular zone 58. The convective stream in the water, shown in Figure 2 by the arrow 78, is thus limited to the inner water volume, the stream flows over the floor 60 of the tank and then upwards on the inside of the forming icewall, and then again to the middle of the water store in the upper region. The convective stream has several purposes. It prevents the carbon dioxide from forming clouds in the water. It also assures uniform cooling of the water store, i.e. gives a certain mixing -444157 effect. The convective stream also simultaneously serves for controlling the ice wall growing on the cooling coil 54, in that the water stream continuously gives up heat to the ice layer 80 at the inwardly facing ice surface 80c of the forming ice layer 80, and therefore limits the radially inward growth of the ice layer. As the water is calm in the outer annular zone 58, i.e. there is no convective stream, the ice can grow unhindered in the annular space, i.e. radially outwards, so that a thick layer 80b forms on the outer circumferential surface of the pipe coil 54, while on the inner side of the pipe coil there is only a very thin ice layer 80a. This has the advantage that the thick ice layer 80b serves as a cold store, while the pine coil 54 is covered on its inner side with only a thin ice layer, which cannot noticeably hinder the rapid transfer of heat from the water to the pipe coi1.

The growth of the ice layer must evidently be controlled from the point of view of energy saving and protection of the tank. This is done by corresponding sensors 73, 74, connected into the central control circuit. The evaporator coil 54 can then also be used as an electrode, to form a sensing circuit with each of the' other electrodes 73 and 74. The outer sensing circuit with the electrode 73 prevents the ice layer growing as far as the tank wall and exerting an unallowable pressure on the tank. The -544157 inner sensing circuit with the electrode 74 controls, together with the convective stream, the growth of the ice layer 80a on the inner side of the cooling coil.

In this manner a direct and very effective cooling of the water is obtained, whereby the water assumes a very uniform low temperature. With this arrangement, there is no need to renounce the advantages of an ice layer as a cold store in favour of direct heat transfer from the water to the cooling coil. The arrangement operates particularly economically and may be installed in a very small space.

The system operates with practically no maintenance. The produced soda water is constantly of the highest quality and may be directly withdrawn for drinking without any mixing of flavouring substances, giving a previously unknown high C02 content.

As stated, the arrangement also allows the drink to be dispensed through a delivery opening of large cross-section. The homogenisation of the drink can therefore be advantageously aided, without producing any other hindering effects, by associating with the delivery opening a gauze through which the drink flows out. The fineness of the gauze is determined inter alia by the actual size of the dispensing opening. It can be easily determined empirically by observing the degree of homogenisation of the dispensed drink.

The gauze also prevents entry of foreign bodies such as -644157 insects into the dispensing opening.

As the control of automatic machines is known as such, and the control functions are clear for the expert from the present description, the illustration and detailed description of the control circuit may be dispensed with.

Claims (7)

1. WHAT WE CLAIM ISϊ1. A method for producing and dispensing cooled water containing dissolved carbon dioxide gas, in which carbon dioxide gas is introduced directly into a pressurized 10 store of cooled water which is divided by a surface cooled to a temperature below 0°C f a forced flow is maintained in the water along one side of the cooled surface, and the carbon dioxide gas is introduced under pressure through a fine-pored body into the flow in a finely divided form, 15 and water is taken out of the store with a simultaneous release of pressure.

2. A method according to claim 1, characterized in that an ice coating is formed in the water store on the cooled surface, of which the growth is limited on the said 20 one side due to the forced flow, so that the ice covering between said flow and the cooled surface is appreciably smaller than the ice covering on the side of the cooled surface facing away from said flow. Apparatus for producing and dispensing cooled -74 415 7 carbonated water, comprising a pressure tight water container containing a cooling element which divides the water container, means for forcing the water to flow along one side of the cooling element, and a carbon dioxide gas introducing device with a porous body arranged to be below the water level and close to the means for forcing the water to flow.

3. 4. Apparatus as claimed in claim 3, including means for introducing the water in finely divided form, which means lies above the water level and is connectable to a pressurised water source.

4. 5. Apparatus as claimed in claim 3 or 4, wherein the container is cylindrical and the cooling element is an evaporator coil which divides the interior of the container into two concentric parts, and the forced flow is produced by a rotating device arranged in the centre close to the container base,so that the flow passes along the inner surface of an ice coating when this is formed on the coi1.

5. 6. Apparatus as claimed in claim 5, wherein sensors are provided on both sides of the evaporator coil, at different distances from the coil, to sense the growth of the ice coating, the sensors being connected in a refrigeration circuit. -87. Apparatus as claimed in claim 5 or claim 6, wherein the rotating deivce is driven without direct contact by a magnetic drive arranged outside the container.

6. 8. Apparatus for producing and dispensing cooled, carbonated water substantially as herein described, with reference to the accompanying drawings.

7. 9. A method of producing and dispensing cooled, carbonated water substantially as herein described, with reference to the accompanying drawings.