WO2004077958A1

WO2004077958A1 - Apparatus for making aqueous mixtures containing ice particles

Info

Publication number: WO2004077958A1
Application number: PCT/EP2004/001187
Authority: WO
Inventors: Ian William Burns; Andrew Baxter Russell; Michael Statham
Original assignee: Unilever Plc; Unilever Nv; Hindustan Lever Limited
Priority date: 2003-03-05
Filing date: 2004-02-09
Publication date: 2004-09-16
Also published as: EP1601254A1; MXPA05009291A; BRPI0408038A

Abstract

Apparatus for making aqueous mixtures containing ice particles comprises a vessel (19) having a base (18) comprising discrete areas (27, 55, 56, 57) which are cooled to a temperature sufficiently low for ice particles having the shape of the discrete areas (27, 55, 56, 57) to form on the surface thereof, areas between the discrete areas on which ice particles do not form (22), and a moving scraper (15) which passes over the surface of base and removes ice particles formed on the discrete areas of the base. The apparatus is suitable for the making and dispensing of iced beverages.

Description

Apparatus for making aqueous mixtures containing ice particles

The present invention relates to apparatus for making aqueous mixtures containing ice particles . In preferred embodiments the present invention relates to apparatus for making and dispensing iced beverages . Iced beverages as used herein, for example the iced beverages which are commonly called slushes, are those which contain both liquid and ice. Heretofore, such iced beverages have been made by scraping the ice off a continuous cooled surface on which it is formed by a scraper which rotates about a horizontal axis. The continuous sheet of ice that is formed on the continuous cooled surface is broken up into irregular shaped particles of ice by the scraper as it rotates . These known machines are described in general terms in USP5967226 (See column 1 line 8 to column 2 line 32 and Figure 1) .

Dispensers which form ice blocks used to cool the water in water fountains or other beverage dispensers are known. In many of these dispensers (see for example USP 4055053, USP 5560211 and USP 5778677) the ice particles are formed in moulds cooled by thermoelectric cooling means . The ice blocks are then released by raising the temperature of the surface of the moulds either by reversing the effect of the thermoelectric means or by allowing the device to stand so that the temperature rises. Devices of this sort do not produce a continuous supply of ice blocks and the need to raise the temperature of the moulds having used energy to cool them down appears to be a wasteful use of energy. The dispenser of USP 5560211 delivers water cooled by the ice blocks but retains the ice blocks within the dispenser. The dispenser of USP 4055053 provides for the separate dispensing of cooled water and the ice blocks. The dispenser of USP 5778677 does permit the dispensing of both ice blocks and cooled water but cannot continuously produce iced beverages. USP 4901539 describes a dispenser for the production of discrete ice particles on the vertical walls of a chamber containing water and ice. The ice particles are dislodged from the walls by warming. This dispenser cannot continuously produce iced beverages .

US Reissue 28924 (USP 3803869) describes a dispenser for hard pieces of ice in which the ice particles are harvested from a horizontal freezing surface by a rotating scraper. The harvested ice particles are then compressed to form rods of ice which are subsequently fractured to give the hard pieces of ice which are separated from any liquid before being dispensed. This dispenser does not therefore produce iced beverages containing both liquid and ice particles.

None of the dispensers described above can produce a continuous supply of ice particles of a desired shape and size which can be dispensed with a liquid beverage to form an iced beverage in a way that is visually attractive to the intended consumer and allows the consumer to observe the process whereby the iced beverage is being prepared.

The present invention provides apparatus for making aqueous mixtures containing ice particles comprising a vessel having a base comprising discrete areas which are cooled to a temperature sufficiently low for ice particles having the shape of the discrete areas to form on the surface thereof, areas between the discrete areas on which ice particles do not form, and a moving scraper which passes over the surface of base and removes ice particles formed on the discrete areas of the base. In a preferred embodiment, the base may be planar and the discrete areas may comprise thermally conductive bodies passing through the planar base, said thermally conductive bodies each having a planar surface which is coplanar with the interior surface of the planar base. Preferably, the thermally conductive bodies have thermally conductive portions extending through the planar base away from the vessel, said thermally conductive portions being cooled by refrigeration means . The thermally conductive portions may contact a cooling body which is cooled by said refrigeration means.

Means for dispensing liquid and ice particles which have been scraped from the discrete areas and which have risen to the top of the vessel may be provided. The dispensing means may comprise an outlet at the top of the vessel and means for admitting liquid beverage composition into the vessel to displace liquid and ice particles through the outlet. The outlet may be located so that the liquid and ice mixture is displaced vertically into the dispensing means or it may be extend outwardly from the upper part of the wall of the vessel, preferably tangentially. The means for admitting liquid beverage composition may comprise a supply tank for holding the liquid beverage composition and pumping means to transfer liquid beverage composition from the supply tank to the vessel. Alternatively, the means for admitting liquid beverage may comprise a pressurised supply tank for holding the liquid beverage composition, means for connecting the supply tank to the vessel and sealing means in the outlet which can be opened to allow passage of liquid and ice particles displaced by liquid beverage composition entering the vessel under the influence of the pressure in the pressurised supply tank. The vessel may be a vertical hollow cylinder made at least in part of a transparent material and may be provided in its upper part with agitating means to prevent aggregation of the ice particles in the vessel and/or to urge the liquid ice mixture towards an outlet extending outwardly from the upper part of the wall of the vessel.

The invention will be illustrated by the following description of an embodiment thereof given by way of example only. The description has reference to the accompanying drawings in which:-

Figure 1 is a schematic sectional view of a first embodiment of an iced beverage dispenser according to the present invention,

Figure 2 is a view taken from the line II-II in Figure 1,

Figure 3 is a cross-sectional view taken along the line III-III in Figure 2,

Figure 4 is a view similar to that of Figure 2 but of a second embodiment,

Figure 5 is a cross sectional view taken along the line V-V in figure 4, and

Figure 6 is a diagrammatic cross sectional view of part of a third embodiment, and

Figure 7 is a sectional view taken in the direction VII-VII of Figure 6

As shown in Figure 1 the iced beverage dispenser is a cart 1 which can be moved from place to place on wheels or castors 2. The cart comprises a cabinet 3 and a vertical hollow column 4 extending from the top surface of the cabinet 3. The whole surface of the column 4 may be transparent or the column may be provided with portions which are transparent so as to enable the interior of the column to be viewed. The cabinet 3 encloses a- supply tank 5 for a liquid beverage composition and a supply pipe 6 whereby the liquid beverage composition can be transferred from the supply tank 5 to the interior of the hollow column 4. The cabinet also contains a compressor 7 and a condensor 8 which are connected to an evaporator 9 by pipes 10, 11 to provide refrigeration means to form the ice particles as will be described hereinafter.

The lower part of the hollow column 4 houses a scraper 15 which is rotated by a motor 16 in the cabinet 3 through a shaft 17 to scrape the upper surface of the ice particle making means shown generally as 18 in Figure 1 and in much greater detail in Figures 2 and 3 and in Figures 4 and 5.

As shown more clearly in Figure 3 the hollow column 4 comprises a cylindrical tube 19 having an outwardly extending annular flange 20 around its lower end by means of which the hollow column 4 is attached to the upper surface of the cabinet 3 for example by nuts 21. The cylindrical tube 19 may be made from glass or a transparent plastic material such as an acrylic plastic for example Perspex®. The thickness of the walls of the cylindrical tube 19 should be such that an effective barrier to the transfer of heat through the walls is provided so as to prevent condensation forming on the outside of the tube as a result of the tube containing a cold mixture of liquid beverage composition and ice. As an alternative (not shown) the cylindrical tube 19 may be constructed with concentric cylindrical walls separated by a gap which contains a gas such as air. A current of air may be directed along the outside of the cylindrical tube 19 to assist in preventing condensation. The air may be warmed, for example by extracting heat from the refrigeration means inside the cabinet 3. The whole of the cylindrical tube 19 may be transparent or the cylindrical tube 19 may have transparent areas through which the interior of the column can be seen.

The ice making means 18 will now be described in more detail with reference to Figures 2 and 3. The base of the cylindrical tube 19 is occluded by a base plate 22. The base plate 22 has a cylindrical section 23 that extends into the lower extremity of the cylindrical tube 19. An annular seal 24 located in an annular groove 25 around the periphery of the cylindrical section 23 ensures a fluid-tight seal. The base plate 22 has an annular section 26 extending outwardly from the cylindrical section 23. The lower extremity of the annular flange 20 of the cylindrical tube 19 abuts the upper surface of the annular section 26. An array of thermally conductive studs 27 extend through the base plate 22. The upper surfaces of the studs 27 are coplanar with the upper surface of the base plate 22. The base plate 22 is preferably made from a material which has a lower capacity to conduct heat than the material from which the thermally conductive studs 27 are made so that ice forms on the ends of the studs 27 but does not form on the upper surface of the base plate 22 between the upper ends of the studs 27. The base plate 22 may be made from a plastic material such as polyethylene terephthalate (PET) or an acrylic plastic such as Perspex®. As the scraper 15 rotates it contacts the upper surfaces of the base plate 22 and the studs 27. The studs extend downwardly below the underside of the base plate 22 and are connected in a thermally conductive manner to an annular cooling plate 28. The studs 27 and cooling plate 28 are made from a thermally conductive material such as a metal eg copper. The cooling plate 28 is cooled by the evaporator 9 which is connected to the underside of the cooling plate in a thermally conducting manner. The evaporator forms part of a refrigeration system contained in the cabinet 3 which also comprises the compressor 7 and the condensor 8. In alternative embodiments (not shown) the cooling plate 28 may be cooled by any known refrigeration system which is capable of reducing the temperature of the cooling plate 28 and the studs 27 to a point where ice forms rapidly on the upper ends of the studs 27. Preferably the temperature of the cooling plate 28 should be less than 0°C possibly as low as -20°C, more preferably in the range -5° to -15°C. Other suitable refrigeration systems include those exhibiting thermoelectric cooling eg peltier cooling. An insulating air gap 29 is provided between the lower surface of the base plate 22 and the upper surface of the cooling plate 28. The insulating air gap is bridged by each of the studs 27. In Figure 3 the studs 27a through to 27e can be seen bridging the air gap 29. Also in Figure 3 can be seen the shaft 17 which drives the scraper 15. The shaft is carried by bearing means 30 passing through the base plate 22. The scraper 15 connected to the shaft 17 by a nut 31.

The hollow column 4 is closed by a cap 36 having an outlet tube 37 leading to a dispensing outlet 38. A motor 39 mounted on the cap 36 turns a shaft 40 and stirrer 41.

The operation of the iced beverage dispenser shown in Figures 1 to 3 will now be described. The interior of the cylindrical tube is filled with a liquid beverage composition. The liquid beverage composition is one which provides the liquid component of the desired iced beverage and is the source from which the ice particles generated by the dispenser are obtained. Suitable compositions contain the following components. The amounts are expressed as w/w% . Ingredient %

Sugars (eg sucrose) 2-25 acidulants (eg citric acid) 0-1.0 preservatives (eg potassium sorbate) 0-0.1 thickeners (eg xanthan or locust bean gum) 0-0.3 flavours qs colourings qs water to 100

Exemplary liquid beverage compositions contain the following components (expressed as w/w%)

Example 1

Ingredient %

Sucrose 8.0

Citric acid 0.4

Lemon and lime flavour 0.3 Potassium sorbate 0.03

Xanthan Gum 0.05

Water to 100

Example 2 Ingredient %

Sucrose 15.0

Lemon concentrate (40® brix) 2.0

Citric acid 0.2

Lemon flavouring 0.05 Potassium sorbate 0.03

Water to 100 In the composition of Example 2 it is preferred to use a clarified lemon concentrate.

The refrigeration system is then activated to cool the cooling plate 28 and the studs 27. The temperature of the upper ends of the studs 27 should be below the freezing point of the composition and is preferably in the range 0° to -20°C, more preferably in the range -5° to -15°C. When the upper ends of the studs have been cooled sufficiently the liquid beverage composition will commence to freeze on the upper ends of the studs 27. As the material of the base plate 22 conducts heat much less readily than the material of the studs 27 the liquid beverage composition only freezes on the upper ends of the studs 27. The cross-section of the studs shown in this embodiment is circular and so discrete circular ice particles form on the upper surface of the studs 17. By using studs of a difference cross- section (for example hexagonal or star shaped) ice particles of the corresponding shape will be formed. The scraper 15 is rotated and scrapes the ice particles from the top surface of the studs 27. The rotation speed of the scraper 15 should be such that the ice particles have time to reach the desired size before they are scraped from the studs 27. Conveniently the rotation speed of the scraper is between 1 and 25, preferably between 5 and 20 most preferably around 12 revolutions per minute. As the ice particles are scraped from the studs 27 they rise up through the liquid beverage and collect in the upper part of the hollow column 4. The rising ice particles cool the liquid beverage composition in the column as they rise to the top. To prevent aggregation of the ice particles the stirrer 41 is activated. When sufficient ice particles have collected in the upper part of the hollow column, dispensing of the iced beverage can commence. The iced beverage consisting of liquid and ice particles is urged into the outlet tube 37 and through the dispensing outlet 38 by introducing liquid beverage composition from the supply tank 5, though the supply pipe 6 and a liquid inlet 32 into the bottom of the hollow column 4. The introduction of this liquid beverage composition into the hollow column 4 displaces the corresponding volume of liquid and ice particles through the dispensing outlet 38. The liquid beverage composition may be transferred from the supply tank 5 to the hollow column 4 by a pump (not shown) . Suitable pumps include manually operated pumps such as the pumps traditionally used to dispense draught beer (the so-called beer engines) or may be electrically powered (for example the pump may be a peristaltic pump) . Alternatively the supply tank 5 may be pressurised with an inert gas such as compressed air, carbon dioxide or nitrogen and the dispensing outlet 11 may be provided with a tap (not shown) to control the egress of iced beverage. When the tap is opened the pressure in the supply tank causes liquid beverage composition to enter the hollow column 4 and to displace iced beverage from the top of the hollow column 4. Cooling means (not shown) may be provided in the supply tank 5 or at a location between the supply tank 5 and the hollow column 4 to reduce the temperature of the incoming liquid beverage composition.

The embodiment described above was intended to be moveable so that the iced beverage can be dispensed wherever the consumer happens to be. The apparatus of the present invention may be fixed in one place for example on the counter of a bar. In this case those parts of the dispenser which were described above as being located within cabinet 3 may be located below the bar counter out of sight of the consumer.

The apparatus of the present invention enable the consumer to watch as the iced beverage is made for them. The visual impact can be enhanced by incorporating lighting into the apparatus of - li ¬

the present invention. For example a strip light 33 (represented by the dotted lines in Figure 1) may be mounted behind the hollow column 4. Unlike the known iced drink dispensers where the ice particles are produced by breaking up a continuous sheet of ice to give irregular shaped ice particles, the apparatus of the present invention produces ice particles of substantially the same size and shape. The shape of the ice particles is determined by the cross sectional shape of the studs 27 and so by using studs of different cross-section, different shapes of ice particles can be produced.

An alternative embodiment is shown in Figures 4 and 5. Many parts of this alternative embodiment are the same as those already described with reference to Figures 1 to 3 and the same reference numerals are used for these parts. In this embodiment the base of the cylindrical tube 19 is occluded by a base plate 50. The base plate 50 has a cylindrical section 51 that extends into the lower extremity of the cylindrical tube 19. An annular seal 24 located in an annular groove 25 around the periphery of the cylindrical section 51 ensures a fluid-tight seal. The base plate 50 has an annular section 52 extending outwardly from the cylindrical section 23. The lower extremity of the annular flange 20 of the cylindrical tube 19 abuts the upper surface of the annular section 52. The base plate 50 is connected to an evaporator 9 on its underside. In this embodiment the base plate 50 is made from a thermally conductive material for example a metal such as copper and has a planar upper surface 53. The planar upper surface 53 carries a circular sheet of thermally insulating material 54 having an array of apertures 55 formed therethrough. As shown in Figure 4 two of these apertures 56, 57 are hidden by the scraper 15. The material from which the circular sheet 54 is made should be such that ice only forms in the apertures 55 where the liquid beverage composition in the hollow column 19 contacts the cold upper surface of the base plate 50. The material of the circular sheet should also be more thermally insulating than the ice that forms in the apertures 55 so that ice continues to form on top of any ice that has formed in the apertures but does not form on the upper surface of the circular sheet 54. As ice continues to form on the top of the ice inside the apertures 54 it builds up above the plane of the upper surface of the sheet 54. The ice that has built up above this surface is then shaved off by the rotating scraper 15.

A further embodiment is shown in Figures 6 and 7. Many parts of this alternative embodiment are the same as those already described with reference to Figures 1 to 3 and the same reference numerals are used for these parts. Figure 6 shows a diagrammatic cross sectional view of the upper part of a cylindrical column 19 having a cap 60. The cap has an impellor 61 supported on a shaft 40 driven by a motor 39. The upper part 62 of the wall of the cylindrical column 19 has an outlet 63 passing through it at a level which is aligned with the impellor 61. As is more clearly shown in Figure 7 the outlet extends tangentially outwards from the column 19. The outlet 63 may be provided with flow control means, for example a tap (not shown) to control the flow of liquid and ice particles through the outlet 63. The apparatus of Figures 6 and 7 may be operated in two ways.

In the first way the outlet 63 is provided with flow control means (not shown) and the column is completely filled with liquid beverage composition and ice particles . When the flow control means is opened to allow liquid and ice particles to pass through the outlet, the liquid and ice particles which had been held above the level of the outlet pass into the outlet under gravity and are dispensed. Rotation of the impellor 61 whilst the flow control means is open directs the ice particles towards the outlet. As more liquid beverage composition enters the column as previously described more iced beverage is displaced through the outlet .

In the second way of operating the apparatus of Figures 6 and 7 the upper extent of the liquid and ice particles in the column is normally level with the lower part of the outlet 63. As liquid beverage composition is introduced into the column as has been described earlier, the level of the liquid and ice particles in the top of the column rises above the lower part of the outlet and can flow into the outlet. Rotation of the impellor 61 assists in directing the ice particles towards the outlet. When the introduction of liquid beverage composition stops the liquid and ice particles will continue to flow into the outlet until the level in the column again drops to the level of the lower part of the outlet 63. In this second way of operating there is no need for flow control means in the outlet .

Claims

1. Apparatus for making aqueous mixtures containing ice particles comprising a vessel having a base comprising discrete areas which are cooled to a temperature sufficiently low for ice particles having the shape of the discrete areas to form on the surface thereof, areas between the discrete areas on which ice particles do not form, and a moving scraper which passes over the surface of base and removes ice particles formed on the discrete areas of the base.

2. Apparatus for making aqueous mixtures containing ice particles according to claim 1 wherein the base is planar

3. Apparatus for making aqueous mixtures containing ice particles according to claim 2 wherein said discrete areas comprise thermally conductive bodies passing through the planar base, said thermally conductive bodies each having a planar surface which is coplanar with the interior surface of the planar base.

4. Apparatus for making aqueous mixtures containing ice particles according to claim 3 wherein the thermally conductive bodies have thermally conductive portions extending through the planar base away from the vessel, said thermally conductive portions being cooled by refrigeration means.

5. Apparatus for making aqueous mixtures containing ice particles according to claim 4 wherein the thermally conductive portions contact a cooling body which is cooled by said refrigeration means .

6. Apparatus for making aqueous mixtures containing ice particles according to any preceding claim wherein the vessel is provided with means for dispensing liquid and ice particles which have been scraped from the discrete areas and which have risen to the top of the vessel.

7. Apparatus as claimed in claim 6 in which the means for dispensing liquid and ice particles comprises an outlet extending outwardly from the upper part of the wall of the vessel

8. Apparatus as claimed in claim 7 in which the outlet extends tangentially from the column

9. Apparatus for making aqueous mixtures containing ice particles according to claim 6 in which the dispensing means comprise an outlet at the top of the vessel and means for admitting liquid beverage composition into the vessel to displace liquid and ice particles through the outlet.

10. Apparatus for making aqueous mixtures containing ice particles according to claim 9 in which the means for admitting liquid beverage comprise a supply tank for holding the liquid beverage composition and pumping means to transfer liquid beverage composition from the supply tank to the vessel .

11. Apparatus for making aqueous mixtures containing ice particles according to claim 9 in which the means for admitting liquid beverage comprise a pressurised supply tank for holding the liquid beverage composition, means for connecting the supply tank to the vessel and sealing means in the outlet which can be opened to allow passage of liquid and ice particles displaced by liquid beverage composition entering the vessel under the influence of the pressure in the pressurised supply tank.

12. Apparatus for making aqueous mixtures containing ice particles according to any preceding claim wherein the vessel is a vertical hollow cylinder made at least in part of a transparent material

13. Apparatus for making aqueous mixtures containing ice particles according to any preceding claim wherein the upper part of the vessel is provided with agitating means.