GB1562491A

GB1562491A - Dissolving and/or dispersing solid material

Info

Publication number: GB1562491A
Application number: GB318/75A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1976-10-04
Filing date: 1976-10-04
Publication date: 1980-03-12

Description

(54) DISSOLVING AND/OR DISPERSING SOLID MATERIAL (71) We, GRAHAME ERNEST JOHN WHITE, of 11 Abbotsway, Monks Risborough, Aylesbury, Buckinghamshire, a British subject and RONALD BAYES, of 22 The Grove, Marton, Teesside, a British subject, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to apparatus and processes for dissolving and/or dispersing solid material, particularly though not exclusively such apparatus and processes for dispensing discrete portions of liquid, for instance for human consumption.

In apparatus for dispensing drinks, for instance, tea coffee. cocoa, soft drinks or soups, liquid is added to a container which contains solid material which then dissolves and/or disperses in the liquid. In order that the dispensing cycle shall be as short as possible, it is highly desirable that the solution and/or dispersion of the solid material shall be as rapid as possible.

According to this invention in one aspect there is provided apparatus for solution and/or dispersion of solid material in a liquid, in combination with a container for the liquid, the apparatus including a support for the container, generating means for sonic and/or ultrasonic vibrations and a tool for applying the vibrations to liquid in the container when supported by the support, the tool and the container support being relatively movable to bring the tool into the contaainer, wherein the arrangement is such that the container is maintained in a predeterminde position relative to the tool while the tool applies the vibrations to the liquid, and the shape of the container and/or of the tool is such that. at least when the container is in said predetermined position relative to the tool, there is defined a region of the container of a shape such that solid material in the region is substantially confined in close proximity to the tool during application of vibrations to the liquid, According to the invention in another aspect there is provided a process for dissolving and/or dispersing a solid material in a liquid including the steps of: - (i) providing solid material and liquid in a container, (ii) introducing a tool into the liquid in the container by relative movement of the container and the tool, and (iii) generating, by means of said tool, a field of sonic and/or ultrasonic vi brations in the liquid in the container, whilst confining the solid material in the field in the close proximity of the tool, in order to dissolve and/or dis perse the solid material in the liquid.

The invention thus makes use of the capacity of sonic, preferably high-frequency, and/or ultrasonic vibrations to cause the rapid solution and/or dispersion of suitable solid material in a liquid.

Preferably the solid material is in the form of a compressed body of particulate material such as a tablet or pellet, since this makes possible good portion control and convenient handling of the material.

Hitherto, it has been usual in dispensing apparatus to add the material to a container in loose powder form, To achieve high efficiency, the solid material must, as mentioned above, be confined in the vibration field within the region of highest intensity. For this reason also it is advantageous that the material is in the form of a single body. The material may be confined by the shape of the container for the liquid or by the shape of the tool or both. The tool may contact the solid material. The most suitable shape for the tool in relation to the solid material, e.g. to a tablet of the material, and in relation to the container will be found to exist for each particular process in which the invention is employed. The tool is desirably shaped so as to concentrate the field of vibration onto the region in which the solid material is confined. The vibrations which are generated are preferably such as to cause near-cavitation or actual cavitation at the interface between the solid material and the liquid. Two or more vibra tion-generating tools may be employed, operating simultaneously on the solid material, and/or a fixed reflector may be placed opposite to a tool so as to increase efficiency.

Preferably the support for the container cooperates with the container to maintain the container in the predetermined position, so that the solid material is suitably located in relation to the tool.

Whe apparatus of the invention may include means for introducing solid material, preferably pelletized or tabletized, into a container. Alternatively containers may be supplied to the apparatus with the solid material already in situ in a desired location.

The apparatus of the invention may include or be combined with or associated with means for supplying the containers, e.g. a vending machine for cups containing solid material to be dissolved or dispersed.

Conveniently the tool is fixed in position and raising means are provided to move the container support, for example a platform, relative to the tool.

All operations in the apparatus may be automatically carried out after initiation of a dispensing operation.

The drinking container used in the apparatus of the invention, which is e.g. a beaker, cup or the like, preferably has a base and a sidewall and one or more projections upwardly directed from the base interiorly of the container, the projection or projections defining a central area of the base suitable to receive solid material.

Such a container is preferably of plastics material.

Other drinking cOntainers useful in the apparatus and process of the invention are those having one or more of the following features:a) a base having in its upper surface a plurality of spaced apart projections adapted to support a body, e.g. a tablet, of solid material above the re mainder of the base and to allow pass age of liquid beneath the body; b) a circumferential recess in the sidewall spaced a distance less than one quarter of the height of the container, prefer ably between 5 mm. and 20 mm., above the base, adapted to receive and locate a filter which will retain solid material between itself and the base; c) in the interior surface, a stacking shoulder spaced by at least 6 mm and preferably not more than 10 mm. from the upper surface of the base of the container. Conventional plastics cups have stacking shoulders at most 5 mm.

above the base. The greater height envisaged provides a space at the hot- tom of the cup (when in a stack) of suitable depth to receive a tablet of solid material.

Various embodiments of the invention will now be described by way of example with reference to the accompanying diagrammatic drawings, in which: Fig. 1 is a vertical cross-section through parts of dispensing apparatus embodying the invention, showing a drinking cup in position and with some parts indicated diagrammatically; Fig. 2 is a vertical section through the bottom part of a cup useful in the invention, showing also a support to be used in conjunction with it; Fig. 3 is a vertical section through the bottom part of another cup useful in the invention; Fig. 4 is a diagrammatic perspective view of another apparatus embodying the invention; Fig. 5 is a diagrammatic view of yet another apparatus embodying the invention; Fig. 6 is a view of parts of the apparatus of Fig. S in a modified version; and Fig. 7 is a vertical section through a cup useful in the invention.

The dispensing apparatus shown in Fig.

1 has a cup support or base 2 of stainless steel on which can be stood cups which are to be filled with liquid. A cup 4 is shown in position. A short distance above its base 5 it has a stacking shoulder 6 joined to the base by a upwardly tapering conical portion 8. The cup 4 is supplied to the dispensing apparatus with a tablet 10 located in the bottom of the cup, the tablet being held against lateral movement by the inner edge of the shoulder 6. The tablet 10 contains, in compressed particulate form, the dried solids which when dissolved andj or dispersed in liquid supplied to the cup by the dispensing apparatus will provide a drink, e.g. soup, milk, cocoa, coffee or tea (containing also if required sugar). Preferably, the shoulder 6 is at least 6 mm for example 8 mm above the base 5 since this allows the tablet to be of suitable size and yet not project above the shoulder.

The apparatus illustrated in Fig. 1 also has a vibration-generating tool 12 also of stainless steel having a head 14 of diameter slightly larger than that of the tablet 10 and a stem 16 connecting the head 14 to an ultrasonic generator and moving means generally indicated by box 18 for insertion and removal of the tool. The tool 12 forms an acoustic coupling connected to the transducer of the ultrasonic generator. The apparatus also includes water supply means generally indicated by box 20 to supply metered quantities of water through a tube 22 into a cup 4 placed upon the base 2. The water is hot when supplied if required for the particular drink being made. The water supply means 20 and the ultrasonic generator and moving means 18 are under the control of control means generally indicated by box 24. The moving means 18 is arranged to move the tool 12 vertically from the upper position in which it permits the placing of a cup 4 upon the base 2 to a lower position illustrated in Fig. 1, in which its head 14 is closely spaced from or engages the tablet 10 in the cup. Conveniently, the tool may rest upon the shoulder 6 of the cup in its lower position. The tool 12 and base 2 are both of stainless steel and the base 2 could be a second tool connected to the same generator as the tool 12. Further vibrating tools may be provided laterally of the tablet 10 as indicated by broken lines 26.

A suitable operational cycle for this apparatus is as follows. With the tool 12 in its upper position, a cup 4 containing a tablet 10 is placed upon the base 2 (which may include locating means to ensure correct positioning of the cup). The cycle is initiated by insertion of a coin and/or by depression of a control button. Immediately, the control means causes the downward movement of the tool from its upper to its lower position, and at the same time causes the water supply means 20 to supply a portion of the water with which the cup is to be filled. Because of the volume displaced by the tool 12 when in the cup, not all of the water can be added at first but the cup can only be filled to a suitable level, e.g. as shown in Fig. 1. Alternatively, all the water can be supplied initially but the cup will not be completely filled when removed from the apparatus. The tool can have a centering action on the cup as it enters so that the cup is maintained in a predetermined position during application of the vibrational energy. When it has reached its lower position and sufficient water has been ad added, the control means causes the ultrasonic generator to vibrate the tool 12 so that the tablet 10 is subjected to high intensity ultrasonic vibrations which cause it to dissolve and disperse rapidly in the liquid. While it is bemg dissolved and dispersed, the tablet is retained by the shape of the cup and by the tool within the most intense portion of the vibrational field generated by the tool 12.

The strength of the field is greatly enhanced by the presence of the base 2 which as mentioned above acts as a reflector.

The most suitable frequency for any operation can easily be found by experiment. Sonic frequencies should be avoided where the sound might be offensive or injurious to people within earshot. A preferred range is 20 k/cs up to 200 k/cs but higher frequencies up to for example 1 m/cs may be found suitable in certain applications.

The power output from the ultrasonic generator must be chosen to suit the particular application. Outputs in the range 50250 watts have been found suitable in different applications. 150--250 watts is preferred in beverage vending.

The period for which the tablet 10 is subjected to ultrasonic vibration to cause complete solution and/or dispersion can be very short, preferably less than five seconds for example two seconds. At the end of the period, the control means 24 causes withdrawal of the tool 12 from the cup and the supply of further water to make up the volume displaced by the tool. At the end of the cycle the cup 4 containing the thoroughly dispersed or dissolved solids can be removed.

The apparatus may additionally be provided with means for receiving a stack of cups and for supplying them during the operating cycle under control means 24 into the correct position of the base, as in known dispensing apparatus. The cups may be placed in the stack with the tablets 10 already in position, preferably secured in some suitable manner, or the apparatus may include means for dispensing the solid material to be dissolved and/or dispersed into the cup or before or after it is located on the base 2 in the operational cycle of the apparatus. In the latter case, powdered material may be used, but if the material is in a single body it is preferred that the upper surface of the base of the cup has a shape of an inverted dome and that the body is in the form of a sphere or other suitable shape which will locate itself under gravity in the bottom of the dome in order that it shall always be in a correct position in relation to the transducer.

It is highly advantageous if the vibrationgenerating tool or a reflector opposed to such a tool extends at least partially round the sides of the material in the base of the cup. Fig. 2 shows one way in which this may be achieved. A cup 30 shown only partially is of similar shape to the cup 4 of Fig. 1 but has in its base an annular recess 32 which provides a projecting ring in the upper surface of the base surrounding a circular area which contains a tablet 34 of dried drink material of a shape to fit snugly into the said area.

The reflector 36, on which the cup 30 stands while a tool enters as in Fig. 1 from above in order to assist in the solution and/ or dispersion of the tablet 34, has a peripheral rim 38 and within the rim an upwardly projecting annular ring 40 of shape corresponding to the recess 32. The ring 40 serves both to locate the cup 30 on the reflector 36 and also to increase the intensity of the filed applied to the tablet 34 because it surrounds the table in the horizontal plane.

Fig. 3 shows part of a cup 42 also useful in the invention. When a tool is inserted into a cup into the close proximity of a tablet as shown in Fig. 1, but no opposed tool outside the cup nor a reflector is provided. It is advantageous to support the tablet above the base of the cup. For this purpose, the cup may as shown in Fig. 3 have a plurality of projections 44 in its base providing an array extending over an area of the base which may be comparable with that of the tablet. The tablet can thus be supported above the base so as to allow flow of liquid beneath the base during the dispersion and solution operation.

The process of the invention can be used for example to cause rapid infusion of tea leaves, which might be placed loose in the base of a cup. Preferably the tea leaves are confined by a suitable paper filter, for instance as in a tea-bag.

The material of such a filter is practically no barrier to ultrasonic vibrations.

Alternatively, the tea leaves may be comfined by a filter incorporated in the cup and located above the base of the cup and for this purpose, the cup of Fig. 3 has a recess 46 in its side wall at a suitable distance above its base. This distance is preferably between 5 mm. and 20 mm., suitably 10 mm. The cup may be supplied to the dispensing apparatus with a filter sheet in position with its edges retained by the recess 46 and with material to be dissolved or infused underneath, or the material may be inserted and the filter placed in position as part of the dispensing cycle.

A tool having a planar end face which is vibrated perpendicularly to that end face will produce in a liquid a stream or jet of liquid moving perpendicularly away from the end face. When solid material is confined by a filter as above described, this stream or jet will wash liquid containing the material dissolved by infusion or the solids out of the space in which the solid is confined.

The apparatus of Fig. 4 is a machine intended to be used, e.g. by the public for the addition of hot water to a cup (one being shown in readiness in the Figure) already containing solids to be dissolved or dispersed, followed by the application of ultrasonic vibration to assist the solution or dispersion. The cup 48 is presented to the machine by the user who may have obtained the cup, complete with solids in situ, from an associated machine which is adjacent or even in the same casing as the machine illustrated. The associated machine may be for instance a coin-operated vending machine.

The machine of Fig. 4 has an outer casing 50, the bottom portion of which is occupied by a water tank and heater 52 and by an ultrasonic frequency generator 54. Heated water from the tank and heater 52 is stored in a header tank 56 from which it is dispensed when necessary through a tube 58. The output from the generator 54 is converted into vibrations by a convertor 60 which vibrates a tool or horn 62. The horn 62 is fixed in position and is located above a vertically movable cup support 64. A drain 65 is provided below the support 64 to collect spilled water.

Means (not shown) for moving the support 64 are provided.

The cycle of operations is actuated by means of push button controls 66. The valves and electrical apparatus required for control are not shown, and may be conventional.

The support 64 has its upper surface shape so that the cup is located in the correct position in relation to the horn 62, e.g. by means of a cooperating rib and recess as shown in Fig. 2 or Fig. 6.

Access to the machine to place a cup on the support 64 may be through a door in the casing 50. In this case, the action of opening and closing the door may be arranged mechanically to cause the raising and lowering of the support 64.

A specific example of the operation of this machine will be described below in connection with Fig. 7.

The apparatus of Fig. 5 is similar to that of Fig. 4 in that the user places the cup 70 in position. It is different in several respects. The cup support 72 is stationary and the convertor 74 and horn 76 are arranged to move vertically in a guide 78.

Pellets of solid to be dissolved or dispersed in the cup are supplied down a chute 79 by a dispenser 80 built into the machine.

A stack of pellets is shown at 82. The cup support 72 holds the cup in position by means of two arms 83 which engage the lip of the cup on opposite sides.

The embodiment of Fig. 6 shows a modification of that of Fig. 5 in which the stationary support 72 holds the cup in position by means of an annular rib 84 which is received by a recess 86 provided in the base of the cup.

The cup 90 of Fig. 7 is similar to that shown in Fig. 6. Its sidewall 90 has a stacking shoulder 92, and in the base 94 there is an upwardly projecting annular rib 96 rectangular in cross-section. The rib 96 provides interiorly a projection surrounding a central area 98 of the base, and exteriorly a recess suitable to receive a correspondingly shaped rib on the cup support in the apparatus with which the cup is used.

When designed for use with the machine of Fig. 4, the cup 90 has dimensions such that the horn 62 can pass through the aperture defined by the stacking shoulder 92 but cannot pass within the rib 96 to contact the central area 98 of the base 94. The rib 96 thus acts to prevent the horn crushing residual solid material against the base which might lead to accumulation of material on the horn. Instead the residual solid material remains within a body of water above the central area 98 which cannot be pushed away by the horn.

In a preferred mode of operation of the machine of Fig. 4 with a cup of Fig. 7, after the cup, with a pellet in position within the rib 96, is in position on the support 64 the generator 54 is switched on.

The support 64 is then moved upwardly until the lower end of the horn is 20mm above the base 94 of the cup (i.e. well above the pellet which does not project above the stacking shoulder 92). Water is added to fill the cup to a depth of 20 mm.

The upward movement of the support 64 is then continued until the horn engages or is very close to the rib 96, which may be 2 mm above the base 94. This movement is preferably at a rate such that the horn does not contact the pellet, but is always relatively advancing towards the pellet as the top of the pellet dissolves or disperses in front of it. This means that the rate of relative advance of the horn must be not greater than the rate at which the pellet is eaten away.

After the horn reaches its point of closest approach to the base of the cup, the support 64 is withdrawn, the cup fully filled and the ultrasonic generator switched off.

An ultrasonic frequency of 30 k/cs at a wattage of 150-250 has been found suitable in such an operation, with a horn of 44 mm diameter and at least 150 mm length.

WHAT WE CLAIM IS: - 1. Apparatus for solution and/or dispersion of solid material in a liquid, in combination with a container for the liquid, the apparatus including a support for the container, generating means for sonic and/ or ultrasonic vibrations and a tool for applying the vibrations to liquid in the contaainer when supported by the support, the tool and the container, wherein the arrangement is such that the container is maintained in a predetermined position relative to the tool while the tool applies the vibrations to the liquid, and the shape of the container and/or of the tool is such that, at least when the container is in said predetermined position relative to the tool there is defined a region of the container of a shape such that solid material in the region is substantially confined in close proximity to the tool during application of vibrations to the liquid.

2. Apparatus according to claim 1 including means to supply liquid into the container when carried by the support.

3. Apparatus according to claim 2 wherein water is supplied into the container during a programmed operational cycle which includes the relative movements of the tool into and out of the contaainer.

4. Apparatus according to claim 3 wherein the programmed operational cycle includes the steps of causing the tool to apply the vibrations to liquid in the container while the container is in said predetermined position relative to the tool and to continue to apply the vibrations as the tool is relatively withdrawn from the container.

5. Apparatus according to any one of the preceding claims wherein the support is a platform and includes one or more projections to engage the underside of a container and hence maintain the container in a predetermined position thereon.

6. Apparatus according to any one of the preceding clailms wherein the tool is fixed in position and raising and lowering means are provided to move the container support relative to the tool.

7. Apparatus according to any one of the preceding claims having a housing within which the container support is mounted, the housing having a door for access to the container support.

8. Apparatus according to claim 7 wherein operation of the door causes movement of the container support.

9. Apparatus according to any one of the preceding claims including, or in combination or association with, a dispensing unit for supplying the containers.

10. Apparatus according to claim 9 including a plurality of containers.

11. Apparatus according to claim 10 as dependent on claim 5 wherein each contaainer has one or more recesses in its underside adapted to receive the said projection or projections of the platform.

12. Apparatus accordinng to claim 10 or claim 11, wherein each container has a base which has in the interior of the container one or more upward proiections to restrict lateral movement of solid material over the ;base and to limit relative movement of the tool towards the base.

13. Apparatus according to any one of the preceding claims wherein the or each container has a base and a sidewall and one or more projections upwardly directed from the base interiorly of the container,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. exteriorly a recess suitable to receive a correspondingly shaped rib on the cup support in the apparatus with which the cup is used. When designed for use with the machine of Fig. 4, the cup 90 has dimensions such that the horn 62 can pass through the aperture defined by the stacking shoulder 92 but cannot pass within the rib 96 to contact the central area 98 of the base 94. The rib 96 thus acts to prevent the horn crushing residual solid material against the base which might lead to accumulation of material on the horn. Instead the residual solid material remains within a body of water above the central area 98 which cannot be pushed away by the horn. In a preferred mode of operation of the machine of Fig. 4 with a cup of Fig. 7, after the cup, with a pellet in position within the rib 96, is in position on the support 64 the generator 54 is switched on. The support 64 is then moved upwardly until the lower end of the horn is 20mm above the base 94 of the cup (i.e. well above the pellet which does not project above the stacking shoulder 92). Water is added to fill the cup to a depth of 20 mm. The upward movement of the support 64 is then continued until the horn engages or is very close to the rib 96, which may be 2 mm above the base 94. This movement is preferably at a rate such that the horn does not contact the pellet, but is always relatively advancing towards the pellet as the top of the pellet dissolves or disperses in front of it. This means that the rate of relative advance of the horn must be not greater than the rate at which the pellet is eaten away. After the horn reaches its point of closest approach to the base of the cup, the support 64 is withdrawn, the cup fully filled and the ultrasonic generator switched off. An ultrasonic frequency of 30 k/cs at a wattage of 150-250 has been found suitable in such an operation, with a horn of 44 mm diameter and at least 150 mm length. WHAT WE CLAIM IS: -

1. Apparatus for solution and/or dispersion of solid material in a liquid, in combination with a container for the liquid, the apparatus including a support for the container, generating means for sonic and/ or ultrasonic vibrations and a tool for applying the vibrations to liquid in the contaainer when supported by the support, the tool and the container, wherein the arrangement is such that the container is maintained in a predetermined position relative to the tool while the tool applies the vibrations to the liquid, and the shape of the container and/or of the tool is such that, at least when the container is in said predetermined position relative to the tool there is defined a region of the container of a shape such that solid material in the region is substantially confined in close proximity to the tool during application of vibrations to the liquid.

10. Apparatus according to claim 9 including a plurality of containers.

the projection or projections defining a central area of the base suitable to receive solid material.

14. Apparatus according to claim 13 wherein the projection or projections are each provided by an upstanding hollow rib formed in the base, the rib thus providing a recess in the exterior face of the base.

15. Apparatus for solution and/or dispersion of solid material substantially as herein described with reference to and as shown in Fig. 1 of the accompanying drawings.

16. Apparatus for solution and/or dispersion of solid material substantially as herein described with reference to and as shown in Fig. 4, Fig. 5, or Fig. 6 of the accompanying drawings.

17. Process for dissolving and/or dispersing a solid material in a liquid including the steps of: (i) providing solid material and liquid in a container, (ii) introducing a tool into the liquid in the container by relative movement of the container and the tool, and (iii) generating, by means of said tool, a field of sonic and/or ultrasonic vi brations in the liquid in the con tainer, whilst confining the solid ma terial in the field in the close proxi mity of the tool, in order to dissolve and/or disperse the solid material in the liquid.

18. Process according to claim 17 including providing a container holding the solid material in a tabletized or pelletized form, and the sonic or ultrasonic vibration is such as to cause fragmentation of the tablet(s) or pellet(s).

19. Process according to claim 17 or claim 18 wherein the solid material is confined in position on the base of the container away from the sidewalls thereof during the application of the said field, and the tool does not contact the sidewalls, so that liquid can move past the tool.

20. Process according to claim 19 wherein the solid material is confined in position by at least one upward projection on the container base, which projection also serves to limit relative movement of the tool towards the base.

21. Process according to any one of claims 17 to 20 wherein the relative movement of the tool and container is coordinated with the application of the said field so that the tool moves relatively towards the solid material as the material closest to the tool is dissolved or dispersed, whereby the undissolved material is maintained close to the tool.

22. Process for ,dissolving and/or dispersing solid material in a liquid substantially as herein described with reference to Fig. 1 of the accompanying drawings.

23. Process for dissolving and/or dispersing solid material in a liquid substantially as herein described with reference to Fig. 4, Fig. 5 or Fig. 6 of the accompanying drawings.