GB2117657A - Equipment for carbonating water - Google Patents

Abstract

The equipment comprises a container for water, means for bringing carbon dioxide and water together in the container with one of them, preferably the carbon dioxide, in a dispersed condition, to cause the water to absorb carbon dioxide and, if the gas is employed in the dispersed condition, means e.g. a gas pump for collecting the unabsorbed gas from the container and recirculating it therethrough or, if the water is in the dispersed condition, means for collecting the carbonated water and recirculating it back to the container. This allows saturation of the water to be achieved at low gas pressures.

Description

SPECIFICATION Gasification of liquids The present invention relates to equipment for gasifying a liquid and more particularly to equip ment for carbonating water.

Equipments are known for use in the home or in retail establishments, such as public houses and cafes, for carbonating water to produce soda water for consumption as such or for use with alcoholic beverages or for making up carbonated soft drinks or so-called "fizzy" drinks using concentrates in the form of syrups.

Conventional equipment intended for use in the home requires high pressure delivery of the carbon dioxide to the water in order to achieve the desired degree of saturation and, thereby, such conventional domestic apparatus must be provided with relatively sophisticated safety devices to guard against the possibility of accidents due to the high carbon dioxide pressures used.

The conventional equipment used in retail establishments can work at lower gas pressures than the domestic equipment if the equipment includes means for reducing the temperature of the water prior to or during carbonation but the use of such cooling means can greatly increase the capital costs of the equipment.

It is an object of the present invention to provide equipment for carbonating water which can operate at low carbon dioxide pressures without requiring cooling of the water.

There is provided by the present invention equipment for carbonating water, which comprises a container for water, means for bringing carbon dioxide and water together in the container with one of them in a dispersed condition to cause the water to absorb carbon dioxide and, if the gas is employed in the dispersed condition, means for collecting the unabsorbed gas from the container and recirculating it therethrough or, if the water is in the dispersed condition, means for collecting the carbonated water and recirculating it back to the container.

The use of a pressure of carbon dioxide insufficient to require the provision of safety devices will generally result in less carbon dioxide in the container being absorbed by the water than would produce saturation thereof. Thus, by recirculating either the undissolved gas or the carbonated water, as the case may be, the concentration of carbon dioxide in the water can be increased and, if the recirculation is continued long enough, saturation of the water can be achieved.

It is presently preferred to use the gas in a dispersed condition and, more particularly, to introduce it into a body of the water in the container in the form of very small bubbles. This is conveniently achieved by passing the carbon dioxide through a foraminous material such as that known as "airstone". Air-stone (believed to be a ceramic foam) is commonly available; finding use, for instance, in domestic aquaria.

In one embodiment of the present invention, gas from a conventional pressurised cylinder of carbon dioxide is passed through a pressure reduction valve into a pressure container containing water so that the carbon dioxide is dispersed in the water, and gas not absorbed during passage thereof through the water, is collected and pumped back to the container by means of a gas pump; the container during this operation being sealed against ingress of the atmosphere. In the embodiment, the pump is located in a pump chamber sealed, in use, against the atmosphere and providing an aperture to which the pressure container may be sealed so that the interior of the container is in communication with the interior of the pump chamber.A line from the gas cylinder is introduced through into the container to disperse the carbon dioxide adjacent the bottom thereof and the gas not absorbed by the water passes from the container into the pump chamber from where it is pumped back into the container by the gas pump through a line passing into the container and is reintroduced into the liquid adjacent the bottom of the container. A further line may be passed through an aperture in the pump chamber and connected to a tap so that carbonated water may be drawn off by the user from the container. It is preferred in the embodiment that the pump chamber comprise a valve by which, when a pressure of carbon dioxide builds up in the pump chamber, the gas can be used to purge atmosphere from the pump chamber and thus avoid pumping air into the container.The valve also permits the remains of the recirculated gases to be vented from the equipment.

The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. lisa perspective view of an equipment in accordance with the present invention.

Fig. 2 is a detail ofthe equipment of Fig. 1 showing parts hidden in Fig. 1.

Fig. 3 is a central vertical section through a second embodiment of the invention.

Fig. 4 is a perspective view thereof complete with a water container, and Fig. 5 is a front elevation of the second embodiment.

Referring to Fig. 1 of the drawings, the equipment comprises a base 1 by which the equipment can be stood on a surface, a cylindrical column 3 erected on the base to contain a pressurised cylinder of carbon dioxide, a housing, generally indicated at 5, mounted on an arm 7 secured by a grip 9 on the cylindrical column, a pressure flask 11 to contain water to be carbonated, and a tap 13 from which carbonated water may be taken off from the container.

The housing 5 comprises a chamber 15 which is air-tight except for an aperture 17 (see Fig. 2) provided in the floor thereof. The housing provides an internally threaded collar 19 which is sealed to the underside of the floor of the chamber to surround the aperture; and the neck of the flask is formed with an external screw thread so that the neck of the container can be screwed into the collar to form an airtight seal therewith and so that the interior of the flask is in communication with the interior of the chamber. The chamber houses a gas pump 23 mounted on supports 25 lying on the floor of the chamber; and the upper wall 27 of the chamber has secured therein a purge valve 29 by which the interior of the chamber can be opened to atmosphere.The upper wall of the chamber also has passed therethrough in an air-tight manner an electrical lead 31 for an electric motor (not shown) for driving the gas pump.

The carbon dioxide cylinder 33 is stood upright in the column 3 and has secured to the top end of the cylinder a pressure reduction valve 35; the valve being connected to a line 37 which is passed through the upper wail of the chamber in an air-tight manner, through the gas pump chamber and into the pressure flask through the aperture in the pump chamber so that the line terminates adjacent the bottom of the container. The line has secured to the bottom end thereof air-stones so that gas passing through the line into the container must pass through the air-stones; the effect of the air-stones being to introduce the carbon dioxide into the water in the container in the form of very fine bubbles. The output of the gas pump is connected to a line 41 which is also passed through the aperture of the pump chamber again to terminate adjacent the bottom end of the pressure flask.This line also is equipped at the bottom end thereof with air-stones so that carbon dioxide passing through the line into the water in the container again appears in the form of very fine bubbles. A third line 43 is also provided to extend from adjacent the bottom of the pressure flask through the aperture of the pump chamber and through the pump chamber and the upper wall thereof in an air-tight manner to connect with the tap.

The pressure reduction valve 33 reduces the pressure of the carbon dioxide in the cylinder to a valve which is incapable of giving rise to any danger and, in use of the equipment, the gas from the pressure reduction valve is passed into the pressure flask through the air-stones to be bubbled through the water contained in the flask in the form of very fine bubbles. Not all the carbon dioxide thus introduced into the water is absorbed thereby, and unabsorbed gas passes through the aperture in the floor of the pump chamber into the chamber and is taken in at the inlet of the pump to be recirculated thereby through the line connected to the pump outlet again to be introduced into the water in the form of very fine bubbles. This leads to a further absorption of the carbon dioxide.This may be continued indefinitely and if continued for sufficiently long would result in saturation of the water with carbon dioxide at the prevailing temperature and pressure but, in practice, the user will be given instruction to continue operation of the gas pump for a predetermined period of time calculated to produce an acceptable level of carbonation of the water.

Alternatively, operation of the pump could be controlled by a timer so that, following start up, it will automatically shut off at the end of the predetermined time.

Once the flow of carbon dioxide is commenced from the gas cylinder, the purge valve may be opened so that air content in the pump chamber and the pressure vessel is vented therefrom.

When carbonation of the water has proceeded for the prescribed time, a user may then draw off soda water through the tap; the user normally only removing the pressure flask for the purpose of refilling the flask with water to produce a further amount of soda water. In order to prevent a loss of carbon dioxide when the flask has been removed, a pressure reduction valve is provided with a control 51 to enable the user to shut off the supply from the cylinder.

The second embodiment illustrated in Figs. 3 to 5, is generally similar to the first embodiment and like reference numerals are used for like parts in the two embodiments. However, the second embodiment is not intended for use as a soda syphon and accordingly does not have the tap 13. It is intended for use with a standard bottle 53 called a "PET" (polyethy -lene terephtholate) bottle to enable soda water to be made up in the bottle and then the bottle to be removed and, if wished by the user, capped. A "PET' bottle is one now in very common use commercially and is therefore cheaply available.

In the second embodiment, the "air-stones" are made up into a generally cylindrical structure 55 compartmented into a lower compartment 55A into which is received the inlet line 37 and an upper compartment 55B into which is received the recirculation line 41 from the pump outlet. The connecting piece 19 in this instance is also somewhat differently formed in having atop wall 56 which comprises an aperture (not shown) matching with the aperture (not shown) in the floor of the pump chamber to admit carbon dioxide to the pump chamber and thus to the pump inlet (not shown).

Further, the arm 7 is in this instance integrally formed with colum 3, and the pump chamber is modified also to house the reduction valve.

Still further, the inlet line is formed internally of connecting piece 19 with a "T" joint 57. The lines 37 and 41 are flexible to permit removal and installation of the bottle and, in these circumstances, the "T" joint is a more convenient joint than, say, an elbow joint. It will be understood in this connection that the upper end of the upright limb 59, of the line 37 need not be closed since it is received in a blind recess 61 in the underside of the top wall 56 of the piece 19.

The second embodiment is operated by turning on the control 51 to admit gas into the bottle via line 31 and compartment 55A of the structure 55 and, as in the first embodiment, gas taken in by the pump is returned to the container via line 41 and compartment 55B of structure 55. The control is turned off after a recommended period of time by the user, who then removes the bottle. No switch is provided for the electrically operated pump and the latter is stopped simply by disconnecting the lead 31 from the main supply.

Claims (13)

1. Equipment for carbonating water, which comprises a container for water, means (hereinafter called dispersing means) for bringing carbon dioxide and water together in the container with one of them in a dispersed condition to cause the water to absorb carbon dioxide and, if the gas is employed in the dispersed condition, means for collecting the unabsorbed gas from the container and recirculating it therethrough or, if the water is in the dispersed condition, means for collecting the carbonated water and recirculating it back to the container.

2. Equipment according to claim 1, wherein said dispersing means disperses the carbon dioxide into the water in the form of bubbles.

3. Equipment according to claim 2, wherein said dispersing means comprises a foraminous material for effecting said dispersion of the carbon dioxide.

4. Equipment according to claim 3, wherein said material is a ceramic foam.

5. Equipment according to any of the preceding claims, wherein said dispersing means comprises a pressure reduction valve to receive carbon dioxide from a source thereof under pressure.

6. Equipment according to any of the preceding claims, wherein said collecting means for unabsorbed gas comprises a pump the inlet of which is connectible to the water container in a gas tight manner to receive unabsorbed gas therefrom and the outlet of which is connectibleto the container to pump carbon dioxide received by the pump back into the body of the water in the container.

7. Equipment according to claim 6, wherein the pump is an electrically driven one.

8. Equipment according to claim 7, wherein the pump is one intended to be driven from a mains supply.

9. Equipment according to claims 6,7 or 8, wherein the container connects with the pump inlet by a screw-threaded connection.

10. Equipment according to any of the preceding claims, wherein a valved outlet for the container is provided to permit carbonated water therein to be drawn off from the container.

11. Equipment according to claim 6 or any of the preceding claims 7 to 10 as dependent thereon, wherein said pump is housed in a chamber comprising a vent valve so that the chamber can be vented to atmosphere.

12. Equipment for carbonating water, substantially as hereinbefore described with reference to Figs. 1 and 2 of the accompanying drawings.

13. Equipment for carbonating water su bstantial- ly as hereinbefore described with reference to Figs. 3 to 5 of the accompanying drawings.