GB2596281A

GB2596281A - Dispensing apparatus

Info

Publication number: GB2596281A
Application number: GB2008654.2A
Authority: GB
Inventors: Ben-David Jonathan; Soon Kim Heung
Original assignee: WLI UK Ltd
Current assignee: WLI UK Ltd
Priority date: 2020-06-09
Filing date: 2020-06-09
Publication date: 2021-12-29
Also published as: WO2021250386A1; GB202008654D0

Abstract

A water dispenser includes a vessel, one or more UVC LED arrays 4 to emit UVC radiation into the vessel; a water inlet 7; a water outlet 8; and means for causing water to take a path which has a length greater than the minimum physical distance between the inlet and outlet, so as to be acted upon by the UVC radiation. Suitably, one or more conduits form an undulating or serpentine path for water to flow between the inlet and outlet. The conduit may comprise one or more straight paths 12 and one or more curved paths 14, 15, or a plurality of curved paths. Alternatively, the conduits comprise two or more nested conduits (70, 71, 72, Fig 18(a)) of different widths. One or more baffles (21, Fig. 4) may be disposed within the vessel, e.g. interdigitated baffles. The dispenser may include a curved inlet, e.g. u-shaped or c-shaped, to one or more conduits adjacent to one or more UVC LEDs to cause UV radiation from the LEDs to diverge. In another embodiment, a screw thread (39, Fig. 6) is mounted in the vessel, comprising a shaft (40, Fig. 5) and one or more helical blades (41, Fig. 5).

Description

Dispensing Apparatus This invention relates to dispensing apparatus. In particular, it relates to dispensing apparatus which dispenses water or other fluids which has been sterilised.

Water dispensers are commonly used. It is generally required to sterilise the water dispensed by them to ensure that it is potable and safe to drink. Methods such as filters have been used in the past but more recently UV radiation has been used to sterilise the water before being dispensed. UV lamps are used to pass UV radiation across a conduit or into a tank of water in order to sterilise the water and destroy any pathogens. Typically this will be UVC radiation.

UVC radiation has wavelengths between 200-290nm and is known to be germicidal so is ideal for this purpose.

Typically, a UV lamp was used for this. In one arrangement, used by the present applicant, water was fed from a reservoir through a coiled, typically helical conduit, which was wrapped around a UV lamp such that UV radiation from the lamp was omitted to the conduit and served to sterilise and disinfect the water in the coiled conduit.

More recently, UVC LEDs have become available. These are much more efficient and notably more compact than a UVC lamp. It is desirable to use such UVC LEDs for efficiency and because of their size in making sure a significant amount of water is fully sterilised by passing across the LED. Typically, an array of LEDs is used, mounted on a board, such as a printed circuit board.

The present invention arose in attempt to provide an arrangement for most effectively sterilising water in a water dispensing acted upon by an array of UVC LED elements.

According to the present invention there is provided a water dispenser including a vessel, one or more UVC LED arrays arranged to emit UVC radiation into the vessel; a water inlet; a water outlet; and a means for causing water to take a path which has a length greater than the minimum physical distance between the inlet and outlet so as to be acted upon by UVC radiation emitted from the one or more UVC LED arrays.

By increasing the path length over the 'physical', ie shortest, distance between the inlet and outlet the exposure time of water to the UVC radiation is 113 increased, improving efficiency of sterilisation.

The means may comprise one or more conduits forming a serpentine or undulating path for water to flow. The conduits may comprise one or more straight paths and one or more curved paths, or a plurality of curved paths.

The UVC LED arrays may be mounted within the vessel, or provided outside it but able to emit UVC radiation into the vessel and any conduits of other water paths within it.

The means may comprise one or more baffles to cause the water to take an indirect path between the inlet and outlet, thus extending the distance the water has to travel.

Preferably, the or each baffle extends from a surface of the housing towards an opposing surface, but does not contact the opposing surface, thereby providing a water path around the baffle.

The baffles may comprise a first group of at least one baffle extending inwardly into the vessel from a first side of the vessel, and a second group of at least one baffle extending inwardly into the vessel in a second generally opposing direction from an opposing side of the vessel. There may be three baffles in each group or more or less than this. There need not be the same number of baffles in each group.

The baffle or baffles extending from opposite directions may interdigitate within the vessel to cause the water to pass over an undulating path. This ensures the water must take the undulating path and not take a 'short cut' between the inlet and outlets.

The means may comprise a nested structure in which water passes through at least one first tube of a first width and also through at least one second tube of a second, smaller width, which is disposed within the first tube, whereby the water is caused to travel through both tubes whilst being acted upon by the UVC LED radiation.

With such a nested structure the radiation form a particular UVC LED may act upon the same water a plurality of times, improving sterilisation and reducing the possibility of any particular part of the water not having come into contact with the sterilising UV radiation.

zo Embodiments of the invention will now be described, by way of example only; Figures 1 and 2 show a further example of a UVC LED reflector and module; Figures 3 and 4 show a second example; Figure 5 shows a third example; Figure 6 shows an exploded view of the components of Figure 5; Figures 7 to 15 show a separate example; Figures 16 and 17 show a further example; Figures 18, 18A and 19 show a further example; Figure 20 shows a further example; Figures 21 and 22 show a further example; Figures 23 to 26C show a further example; Figures 27 and 28 show a further example, and Figure 29 to 34 show further examples.

Figures 1 and 2 show a first example. This comprises a housing 1 which is typically a cylindrical housing having; a closed bottom 2 and side walls 3. A UVC (\I 15 LED array 4 is mounted on the bottom surface 2. This comprises a number of UVC LEDs 5 and appropriate circuitry for driving these and these will be LEDs emitting radiation in the UVC bandwidth. UVC LEDs are commonly available per se. a)

O A water path is formed by a coil conduit 6 having an inlet 7 and an outlet 8.

In the example shown the inlet and outlet are both at the top but they may be otherwise arranged.

Between the inlet 7 and outlet 8 the conduit traverses an undulating path. In the example shown, from the inlet the conduit is straight to its the bottom where it has a curved portion 9 which causes the water to return in the direction generally parallel but opposite to the direction of the inlet 7, via a straight part 10. From here it passes to a further 1800 curved part 11 and so on. After several undulations (the number of which may vary) the conduit passes through a straight part 12 via an angled part 13 to the outlet B. This is mounted within the housing 1 such that water within the conduit is acted upon by the LED array 4. Each LED might be arranged underneath or generally in the vicinity, of one of the curved parts such as 14, 15, for example but not necessarily.

The conduit may instead be curved, instead of having curved and straight portions. Any conduit which is undulating or serpentine may be used in other embodiments.

Thus, as water passes from the inlet to the outlet it traverses a path which is much greater than the physical distance between the inlet and outlet, and is acted upon by each of the LEDs in turn, meaning that over the whole distance of the water travels, the water is acted upon by radiation from all of the LEDs and therefore is sterilised to maximum efficiency.

In this example, the upright parts such as 10 and curved parts 9 form part of a generally ring-like (eg circular or oval) cross-section structure (seen from above in this example) and the outlet 11 is in the middle of these (ie is within the outer ring formed by parts 9, 10, etc). One of the LEDS 5a may be mounted directly under the outlet 8 to emit UV radiation directly up and into the outlet.

The housing is made of a reflective material such as, for example, stainless steel, aluminium or other material which can reflect radiation. It may also be Teflon or many other materials. The conduit may be made of quartz or other glass or other material which is transmissive of UVC radiation and therefore through which the UVC radiation can pass in order to sterilise water within the conduit.

Figures 3 and 4 show an example comprising an inlet 7 and 8 outlet which pass water into vessel 20. This vessel will also be mounted inside a housing, such as the one shown in Figure 1 or will form the housing itself. The inlet and outlet 7 and 8 may be vertically disposed as shown (ie extend perpendicularly from the plane of the base of the vessel and the UVC LED array is positioned on the surface. The inlet and outlet are not connected to the bottom surface and there is a gap between the bottom of the inlet and outlet and the surface. Within the vessel 20 is provided a UV transmissive baffle or plate 21. In other embodiments more than one such baffle may be provided on one or more inner surfaces of the vessel Thus, water from the inlet surface passes into the vessel. The baffle 21 is preferably connected to or integral with the base and sides of vessel 20 but there is a gap between the top of the baffle and the top of vessel 20. Thus, water from the inlet passes into the vessel and is forced to travel up one side of baffle 21, across the top of this and down again where it eventually reaches the outlet 8. This is clearly shown in Figure 3. Thus, results in water path which is relatively long and the water is acted upon by LEDs in the UVC LED array during its transverse along the path.

113 Figures 5 and 6 show an embodiment in which an inlet 7 and outlet 8 are also provided together with a vessel 30. The vessel comprises an auger or screw thread 31. In this example, the UVC LED is provided towards the top of the vessel. The structure comprises attachment bolts 33, a cooling part 34, a PCB support 35 for supporting the LED array 32, a further plurality of bolts 36 for securing part of the assembly, a plate 37 made of, for example, quartz or glass which is therefore transmissive to UVC radiation, or other suitable material. The apparatus also includes the screw thread part 39 and these parts then fit within the vessel 30.

Note that this and the previous embodiment and other embodiments, there 20 may be a separate housing and vessel, or the housing and vessel can be the same component.

The screw thread part 39 includes a central shaft 40 and a helical blade 41 (or a heraldic of blade). As shown in Figure 5, the inlet 7 and outlet 8 extend into the housing 30 to a certain extent and the blade extends outwards from the shaft. The helical blade creates water turbulence which improves sterilisation efficiency and extends the distance the water travels.

It may, in some embodiments, but not necessarily, extend to an extent which overlaps the entrance to the inlet and outlet. In these embodiments, one or more of the blades lie in between the inlet and outlet, preferably two or more of these (two are shown in the Figure), so that water from the inlet cannot pass directly to the outlet but must be directed by the blades of the screw thread to take a path longer than the direct distance between the inlet and outlet.

The UVC LED array 32 is mounted above the blade to act upon the water.

The blades will typically be of a UV transmissive material. Again, the vessel may be of a reflective or transmissive material such as stainless steel, aluminium, Teflon and so on.

Figures 7 to 15 show an embodiment in which dividers/baffles are added 113 into the housing extending down from the top plate, so as to provide a longer flow path for the water between the inlet and outlet, whilst being acted upon by the UVC LED. In this case, the UVC LED is preferably at the top. Note that in any embodiment the UVC LED may be at the bottom or indeed the sides, or more than one UVC LED array may be provided.

The embodiment provides a plurality of bolts 50, a cooling part 51, a PCB support 52 and a UVC LED array 53. In this embodiment, and that of the previous one and others, the UVC LED board may require cooling. Thus, a cooling block 51 is provided which may be made of reflective/conductive material such as aluminium or stainless steel to be able to take heat from the LED array and cool it. This is preferably in contact with water in the chamber or housing 1 for better cooling so that the heat can be dissipated into the water within the housing Further bolts 54 secure these parts in place.

A cooling part 55 comprises a plate 56 and baffles 57 extending downwardly from the plate. In this example two are shown but there may be one or more than two. The housing also includes one or more upwardly providing baffles 58, in this case three, which are arranged such that the baffles 57, when the plate 56 is mounted on the housing, can sit inbetween respective ones of the baffles 58. That is, they interdigitate when the plate 56 is mounted upon the housing the baffles 57 do not reach the bottom of the housing and the upwardly extending baffles 58 within the housing do not reach the undersurface of plate 56. Thus, water from the inlet is constrain to move past each baffle in turn in an undulating manner, again increasing the flowpath between inlet and outlet. This is shown most clearly in Figures 11 and 13. The flowpath is shown in Figure 11. In this example the inlet 7 is located above the outlet 8.

In one example four LEDs are provided on the LED array, as shown in Figures 9 and 10. The plate is of a transmissive material and one particular advantageous material may be Teflon or Quartz. Teflon has exceptional resistance to high temperatures, chemical reactions, corrosion and cracking under stress.

113 Teflon products are also very high UV transmittance and can provide a good alternative to cork or other materials traditionally used. A typical example of Teflon is PTFE but one example which is more preferably used is FEP which has very good UV transmittance. Any UV transmissive Teflon may be used.

A shown in Figures 9, 10 and 12 the bottom surface of the plate (the plate where the baffle extends outwardly from) is most preferably not flat but has a curve in its surface, typically of a U or C shape. This amplifies UV light and serves to increase UV exposure of water within the tank or housing. The dashed lines in Figure 9 show typical UV radiation paths and Figure 12 is an exploded view which shows how these U shape coils cause the UVC LED radiation to divert outwards at the interface between the surface of the plate and water/air within the housing to cause the UVC radiation to diverge and therefore reduce the chance of areas where water may not come into contact with the UVC radiation.

Figures 16 and 17 show an embodiment in which both the top plate and housing including 3 baffles which interdigitate as before. These are baffles 16 extending from the top plate and baffle 61 extending from the housing. Of course, there may be more baffles in the top or bottom parts than this.

Figure 16 also shows the U shape or curved parts on the bottom of the plate and this is shown at 62. These positions then line up with LEDs and UVC LED array.

Figures 18, 18A and 19 show a further embodiment from the inlet 7, from the bottom in this case, water passes through a nested array of tubes 70, 71, 72. Note that although three such nested tubes may be arranged the number may be more than this or less. These may be coaxial. A first smallest diameter tube 70 extends from tube 70 upwards in the housing 1. A second, wider tube, 71 is provided outside inlet 7 and tube 70 is open at its top with a space inbetween this and the UVC LED (which is also at the top in this embodiment) so that water passes upwards through inner tube 70 and then passes down tube 71. Tube 71 is again also open at its bottom so that water pass from here to a third wider diameter 113 tube 72 and passes up this, as shown by the arrows A in Figure 18. In one embodiment, inner tube 70 may be of 9cm diameter, tube 71 of 30mm diameter tube 72 of 40cm diameter and the housing of 52cm diameter. Any dimension may be used, however, in a nested arrangement in which progressively wider tubes are used. The more 'layers' (nested tubes) the better.

This embodiment, or others may include the curved, eg or C shape part, to the UVC reflector.

As shown in Figure 16, this embodiment comprises bolts 100, a cooling body 101, PCB support 102, LED PCB array 103, further bolts 104, a quartz, glass or other transmissive cylindrical body 105, a seal 106, housing 107 and bottom components for securing the housing, including sealed bolts and a bottom cap 108.

Note that in this and other embodiments, in addition to, or instead of a UVC LED array at the top it may also alternatively be provided at the bottom (ie where the inlet comes in in Figure 18), or on the side. Tubes 70 to 72 may be made of Teflon, cork or other UV transmissive or reflective material.

Figure 20 shows another example of nested tubes. These may be quartz or Teflon tubes 110, 111 and 112.

Figure 21 and 22 show an embodiment in which a single relatively large diameter Teflon or other transmissive or reflective sleeve 120 which is placed within the housing 1 but spaced inwardly from this to leave a gap between the side walls of the sleeve and inside surface of the housing. A seal 121 is provided between the inlet 7 and outlet 8. The gap is provided allowing water to pass at the top and bottom of the sleeve between this and the housing. Thus, from the inlet 7 water cannot pass direct to outlet 8 but must pass down the gap 121 between the sleeve and the housing into the inner volume of the sleeve, up the inside of the sleeve, back to the gap between the sleeve and housing and from then into the 113 outlet, as shown by arrows B. Again, this increases the distance between the inlet and outlet in order to maximise exposure to UVC. In this case, it may be desirable to have a UVC LED at the top 125 and also at the bottom 126.

An exploded view of this is shown in Figure 22 illustrating the sleeve 120 and housing 1. This also shows seals 128 and 129 and the seal 130 which in use sets a position sealing the gap between the sleeve and the housing and part between the inlet 7 and outlet 8 so as to block water passing directly from the inlet to the outlet.

Nested tubes enable water to pass twice or more through radiation emitted by one or more UVC LEDs, reducing the likelihood of any pockets of water not being impinged upon by the UV radiation.

Figures 23 to 25C show an embodiment in which inside the housing 1 there is provided a plurality of tubes extending generally radially within the housing such that radiation passes through each of the tubes such that water must pass through each of the tubes. The tubes are shown at 140 and the Figures 25A to 25C and 24. In this case, a UVC LED array may be provided on the side 141 of the housing. This may be of relatively long length dimension corresponding to most of the length of the tubes 140 for most efficient radiation and sterilisation. Again, the housing may be of reflective material such as aluminium, stainless steel and the tubes are courts and so on. Instead at the side, the UVC LED array may be arranged at the bottom, middle, top or anywhere between the bottom and top, as before. Figures 25A to 25C show various arrangements. In this case, the inlet and outlet are shown at the top from the respective tubes. Water passes through all the tubes in turn so these are connected at the top and bottom by curved or return sections for example or by seals such as seal S in Fig 26B. Water flows between the tubes in recesses R (Fig 25C) Seals are provided at the top and bottom, sealing these recesses, which ensure water flows from one pipe to the next.

Figures 26A to 27 show an embodiment in which a radial array of tubes is 113 provided to form a ring-like array of tubes but also in which there is a central main chamber/conduit lying within the radial array of tubes and to which the outlet is connected. This is most clearly shown in Figure 27. In this case, water enters through outer array to the one of the outer tubes and passes through the outer tubes. UVC LED may be provided on the top or bottom, or on the side. After passing through all tubes in the outer array of tubes the water passes to an inner main chamber which is connected to one of the outer tubes and is provided radially within the outer array of tubes. These may be typically of larger diameter than the smaller diameter outer tubes. In other embodiments this need not necessarily be so. The outlet 8 is then taken from this inner main chamber and the main chamber is shown at Figure 26D. Figure 27 shows water passing from the inlet 7 where it passes through all the outer tube and then into the inner tube (through an inlet 170 to the inner tube) through the inner tube and then out from the inner tube to the outlet 8. The inner tube is designated 175. There will of course be a connection between the outlet 174 from the outer most tubes via the main tube 170.

Alternatively, water may pass directly through the housing.

The UVC LED array may be arranged on the side (as shown in Figure 26A and 26B) or on the top or bottom, as shown in Figure 26C. Any embodiments may have UVC LED arrays at the top, bottom and/or one or more sides.

Figures 29 and 30 show an embodiment in which water passes from an inlet 7 through a coiled path 200 to a straight path 201 and into an outlet 202. The housing in this case is formed by the cap, in effect forming an end cap 203, of reflective material. This will also generally have a top lid (not shown). The UVC LED array, provided on the top (above the cool part 200) or on the bottom under the cool path 200 to act upon water within the cooling part. The housing has a wide diameter part 204 around the coiled part 200 and then leads to a narrower diameter projection 205 housing the straight part 201 so that UVC radiation is reflected by the reflective walls of the housing to the end parts of the tube 101/102 in order to ensure that UVC radiation is reflected to the outlet 202 which may be the actual dispensing outlet, thus providing sufficient sterilisation of water at the actual point of exit from the outlet (ie the faucet) Figures 31 and 32 show a modification in which the coiled tube is longer. UVC LED arrays 210 and 211 are provided at the top and bottom, Note that by providing an inner support, within the coil, one or more UVC LEDs or LED arrays may alternatively or additionally be provided within the coli, for additional sterilisation, and to make sure the water in the coil is acted upon by UVC radiation from outside and inside, making the radiation more even and even more effective. FIG 32 shows this with an external housing 212 surrounding the coil. This will typically be of be of UV reflective material to improve sterilisation further.

Figure 33 shows a modification with a slightly different configuration of inlet and outlet. This shows upper 210 and lower 222 LED arrays but LEDs may also be provided within the coil.

Figure 23 shows a modification in which an inner tube 215 is provided within the coil, this may support one or more UVC LEDs or arrays. It forms part of the water path itself (being joined to the inlet to the coiled tube 200) and thus provides cooling for the LED array or arrays mounted upon it.

Claims

Claims 1. A water dispenser including a vessel, one or more UVC LED arrays arranged to emit UVC radiation into the vessel; a water inlet; a water outlet; and a means for causing water to take a path which has a length greater than the minimum physical distance between the inlet and outlet as to be acted upon by UVC radiation emitted from the one or more UVC LED arrays.
2. A water dispenser as claimed in claim 1 wherein the UVC LED arrays are 113 mounted within the housing.
3. A water dispenser as claimed in claim 1 and 2 wherein means for causing water to take the path comprises one or more conduits forming an undulating or serpentine path for water to flow between the inlet and outlet.
4. A water dispenser as claimed in claim 3 wherein the conduit comprises one or more straight paths and one or more curved paths, or a plurality of curved paths.
5. A water dispenser as claimed in claim 3 wherein the conduits comprises two or more nested conduits of different widths, arranged such that water must pass through two or more of the nested conduits between the inlet and outlet, whilst being acted upon by UVC radiation.
6. A water dispenser as claimed in any preceding claim comprising one or more conduits for the water, adapted to provide a path through which water must travel which is greater than the minimum physical distance between the inlet and outlet, and wherein at least some of the conduits together provide a generally ringlike structure.
7. A water dispenser as claimed in claim 6 wherein, in addition to the ring-like structure of conduits, an inner conduit is formed within the ring formed by the ringlike structure and water is caused to pass between the conduits forming the ring-like structure and also through the inner conduit when passing between the inlet and outlet.
8. A water dispenser as claimed in any preceding claim comprising one or more baffles disposed within the vessel, which baffles cause water to pass around the baffle between the inlet and outlet.
9. A water dispenser as claimed in 8 wherein the or each baffle extends from a surface of the housing towards an opposing surface, but does not contact the 113 opposing surface, thereby providing a water path around the baffle.
10. A water dispenser as claimed in claim 8 or 9 comprising a first group of at least one baffle extending inwardly into the vessel from a first side of the vessel, and a second group of at least one baffle extending inwardly into the vessel in a second generally opposing direction from an opposing side of the vessel.
11. A water dispenser as claimed in claim 10 wherein the baffle or baffles extending from opposite directions interdigitate within the vessel to cause the water to pass over an undulating path.
12. A water dispenser as claimed in any preceding claim including a curved inlet to one or more conduits adjacent to one or more UVC LEDs in a UVC LED array, to cause UV radiation from the one or more UVC LEDs to diverge.
13. A water dispenser as claimed in claim 12 wherein the curved part is U-shaped or C-shaped.
14. A water dispenser as claimed in claim 1 comprising a screw thread mounted within the vessel and having a shaft and one or more blades mounted to the screw 30 thread, screw thread forming the path through which the water is constrained to flow.
15. A water dispenser as claimed in claim 14 wherein the screw thread comprises a shaft and one or more helical blades.
16. A water dispenser as claimed in claim 14 wherein the inlet and/or outlet 5 extend a distance into the housing and one or more of the blades of the screw thread overlap with the inlet and/or outlet to cause water to flow across the one or more blades between the inlet and outlet.