Wipes with foam

Abstract

A foaming component for use in a foaming liquid dispenser, and an insert arranged so that it may be inserted into a liquid dispenser comprising the foaming component. The foaming component comprises a liquid chamber; an air chamber; a sparging component, which comprises a sparging interface and a foaming region; an exit aperture; and a pumping mechanism. The pumping mechanism is arranged such that it can transfer liquid from the liquid chamber directly to the foaming region, and air from the air chamber to the foaming region, via the sparging interface. The forcing of air through the sparging interface causes bubbles to form in the liquid located in the foaming region, resulting in a foamed mixture for dispensing. The pumping mechanism is then used to transfer the foamed mixture from the sparging component through the exit aperture, wherein the sparging interface is arranged such that at least a portion of the foaming region is positioned in between opposing surfaces of the sparging interface.

Claims

1. A foaming component comprising: a liquid chamber; an air chamber; a sparging component comprising a sparging interface and a foaming region; an exit aperture; and a pumping mechanism, the pumping mechanism being arranged to: transfer soap comprising suspended particles therein from the liquid chamber to the foaming region without passing through the sparging interface; transfer air from the air chamber, through the sparging interface, and to the foaming region, whereupon the forcing of air through the sparging interface causes bubbles to form in the soap containing suspended particles therein in the foaming region forming a foamed mixture for dispensing; and transfer the foamed mixture from the sparging component through the exit aperture, wherein the sparging interface is arranged such that at least a portion of the foaming region is disposed in between opposing surfaces of the sparging interface.

2. The foaming component according to claim 1, wherein: the foaming component comprises a stationary section and a translatable section that is translatable with respect to the stationary section; and the stationary section and translatable section combine to form the liquid chamber and the air chamber.

3. The foaming component according to claim 2, wherein: the foaming component is arranged such that translation of the translatable section towards the stationary section reduces both the volume of the liquid chamber and the volume of the air chamber thereby providing the pumping mechanism.

4. The foaming component according to claim 2 wherein: the translatable section is resiliently biased in a direction of increasing separation from the stationary section, thus requiring an external force to translate the translatable section towards the stationary section thereby to effect pumping.

5. The foaming component according to claim 2, wherein: the sparging component is formed as part of the translatable section.

6. The foaming component according to claim 2, wherein: the translatable and stationary sections are annular; the liquid chamber is centrally disposed; and the air chamber surrounds the liquid chamber.

7. The foaming component according to claim 2, wherein: the sparging component is formed as part of the stationary section.

8. The foaming component according to claim 1, wherein: the sparging interface defines a cylindrical foaming region between inner and outer surfaces of the sparging interface.

9. The foaming component according to claim 8, wherein: the outer and/or inner surfaces are annular.

10. The foaming component according to claim 8, wherein: the outer and/or inner surfaces have a substantially fixed radius over a length thereof.

11. The foaming component according to claim 8, wherein: the outer and inner surfaces are concentrically disposed.

12. The foaming component according to claim 8, wherein: the sparging interface further defines a bypass aperture in the outer surface through which bypass aperture air can be pumped into an air pocket formed within the inner surface, whereupon air can be forced through the inner surface into the portion of the foaming region disposed between the outer and inner surfaces.

13. The foaming component according to claim 12, further comprising: a plurality of bypass apertures defined by the sparging interface.

14. The foaming component according to claim 13, wherein the plurality of bypass apertures are substantially perpendicular to the tangent of the outer surface and/or to the tangent of the inner surface, and wherein the plurality of bypass apertures are substantially perpendicular to a central axis of the outer surface and/or inner surface.

15. The foaming component according to claim 8, wherein: a pore size of the inner surface of the sparging interface is different to a pore size of the outer surface of the sparging interface, wherein the pore size of the inner surface of the sparging interface is greater than the pore size of the outer surface of the sparging interface.

16. The foaming component according to claim 1, wherein: the sparging interface defines an outer surface surrounding an inner surface, a portion of the foaming region being disposed between the outer and inner surfaces.

17. The foaming component according to claim 1, wherein: the sparging component is formed such that the foaming region comprises more than one foaming zone.

18. The foaming component according to claim 17, wherein the foaming region comprises a first zone, which is disposed between two sparging surfaces of the sparging interface.

19. The foaming component according to claim 18, wherein translation of the translatable section causes foaming of soap comprising suspended particles therein in the first zone of the foaming region and transfer of the foamed soap comprising suspended particles therein to a second zone of the foaming region.

20. The foaming component according to claim 18, wherein translation of the translatable section causes foaming of soap comprising suspended particles therein in the first zone of the foaming region and transfer of the foamed soap comprising suspended particles therein to a second zone of the foaming region.

21. The foaming component according to claim 20, wherein the sparging interface defines a cylindrical first zone of the foaming region between two surfaces of the sparging interface.

22. The foaming component according to claim 21, wherein the two surfaces of the sparging interface of the first zone are different from two surfaces of the sparging interface of the second zone.

23. The foaming component according to claim 22, wherein the two surfaces of the sparging interface of the second zone are disposed within the two surfaces of the sparging interface of the first zone, and wherein the first and second zones are linked by one or more foaming conduits.

24. The foaming component according to claim 23, wherein the two surfaces defining the second zone are centrally disposed within the two surfaces defining the first zone.

25. The foaming component according to claim 23, wherein there are two foaming conduits.

26. The foaming component according to claim 1, further comprising: a liquid storage chamber for supplying soap comprising suspended particles therein to the liquid chamber.

27. The foaming component according to claim 15, further comprising: a one-way valve between the liquid storage chamber and the liquid chamber arranged to permit fluid to flow from the liquid storage chamber to the liquid chamber.

28. The foaming component according to claim 16, wherein: the sparging interface comprises a porous membrane.

29. The foaming component according to claim 17, wherein: the porous membrane is arranged to have a pore size in the range 10-300 μm.

30. The foaming component according to claim 1, wherein: the foaming component is for a liquid dispenser.

31. An insert comprising: a foaming component comprising: a liquid chamber; an air chamber; a sparging component comprising a sparging interface and a foaming region; an exit aperture; and a pumping mechanism, the pumping mechanism being arranged to: transfer soap comprising suspended particles therein from the liquid chamber to the foaming region without passing through the sparging interface; transfer air from the air chamber, through the sparging interface, and to the foaming region, whereupon the forcing of air through the sparging interface causes bubbles to form in the soap containing suspended particles therein in the foaming region forming a foamed mixture for dispensing; and transfer the foamed mixture from the sparging component through the exit aperture, wherein the sparging interface is arranged such that at least a portion of the foaming region is disposed in between opposing surfaces of the sparging interface, wherein the insert is arranged to be inserted into a liquid dispenser.

32. An insert according to claim 31, wherein the insert is disposable.

33. A liquid dispenser comprising a foaming component, the foaming component comprising: a liquid chamber; an air chamber; a sparging component comprising a sparging interface and a foaming region; an exit aperture; and a pumping mechanism, the pumping mechanism being arranged to: transfer soap comprising suspended particles therein from the liquid chamber to the foaming region without passing through the sparging interface; transfer air from the air chamber, through the sparging interface, and to the foaming region, whereupon the forcing of air through the sparging interface causes bubbles to form in the soap containing suspended particles therein in the foaming region forming a foamed mixture for dispensing; and transfer the foamed mixture from the sparging component through the exit aperture, wherein the sparging interface is arranged such that at least a portion of the foaming region is disposed in between opposing surfaces of the sparging interface.

34. A liquid dispenser according to claim 33, further comprising an insert, wherein the insert comprises the foaming component.

35. A liquid dispenser according to claim 34, wherein the insert is disposable.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) In order that the invention may be more readily understood, it will be described further with reference to the figures and to the specific examples hereinafter.

(2) FIG. 1a shows a cross-section of a disposable insert comprising a foaming component.

(3) FIG. 1b shows the disposable insert of FIG. 1a having undergone a 90 degree rotation about the longitudinal axis of the disposable insert.

(4) FIGS. 2a-c shows the sequential progression of a discharge stroke of the disposable insert.

(5) FIGS. 3a-c shows the sequential progression of the recharge stroke of the disposable insert.

(6) FIG. 4a shows a cross-section of a fixed insert comprising a foaming component, charging of the insert with liquid is illustrated (evenly dashed lines correspond to air and solid lines to liquid).

(7) FIG. 4b shows the disposable insert of FIG. 4a during actuation.

(8) FIGS. 5a and 5b show foam production and flow (dot-dashed lines correspond to foam) in the insert of FIGS. 4a and 4b.

(9) FIG. 6 shows the sparging component of the insert of FIGS. 4 and 5 in cross-section 90° through the lateral axis of the insert.

DETAILED DESCRIPTION

(10) FIG. 1a shows an exemplary foaming component 1 having a stationary section 7 and a translatable section 9 which combine to form a liquid chamber 3 and an air chamber 5. Attached to the translatable section 9 there is provided a sparging component 11 comprising a sparging interface 13 and defining a foaming region 15. It can be seen that the foaming region 15 is disposed between opposing surfaces of the sparging interface 13. In the exemplary arrangement shown, the sparging interface 13 comprises a radially outer surface 13a and a radially inner surface 13b. There is also provided bypass apertures 21. Both surfaces 13a and 13b are annular in cross-section and co-centric.

(11) A one-way liquid intake valve 20 enables liquid to pass from outside the liquid chamber 3, through the liquid intake valve 20 and into the liquid chamber 3. Thus the foaming component 1 may be provided as part of a replacement cartridge for a liquid dispenser, wherein the liquid intake valve 20 is situated between a liquid storage chamber of the replacement cartridge and the liquid chamber 3 of the foaming component 1.

(12) A one-way air intake valve 19 allows air to pass from outside the air chamber 5, through the air intake valve 19 into the air chamber 5.

(13) Thus during a recharge stroke, which will be discussed below, air and liquid can be replenished into the liquid 3 and air 5 chambers. Of course, for one-shot liquid dispensers such recharging is not required.

(14) There is also shown an exit aperture 17 through foamed liquid to be dispensed is ejected.

(15) The basic operation of the foaming component 1 is as follows. The translatable section 9 is translated into the stationary section 7 effecting a compression of the liquid chamber 3 and the air chamber 5. Liquid is thus forced out of the liquid chamber 3, through a liquid transfer valve 27 into foaming region 15. Air is thus forced out of the air chamber 5 through an air channel 23. Some of this air then passes through the outer surface 13a of the sparging interface, whereupon the air is split into a multitude of air streams, into the liquid in the foaming region 15, whereupon air bubbles form in the liquid from the multitude of air streams and the liquid is foamed. The remainder of the air passes through the bypass aperture 21 into an air pocket 25 defined by the sparging interface 13 and then through the inner surface 13b, whereupon air is split into a further multitude of air streams, and passes into the liquid in the foaming region 15 causing further air bubbles to form in the liquid.

(16) Thus the liquid in the foaming region 15 is sparged with air that is infused perpendicular to the direction of flow of the liquid and from two opposing directions in cross section. In other words, the liquid may be sandwiched in cross section between the opposing surfaces of the sparging interface. It will be recognised that in the exemplary arrangement however, the 3-dimensional geometry is such that the sparging interface defines between outer and inner surfaces thereof a substantially cylindrical foaming region. Air can then be sparged into the cylindrical foaming region in radially inward and outwards directions normal 5 to the cylinder surface.

(17) The resulting foamed liquid is then dispensed through the exit aperture 17.

(18) FIG. 1b shows the foaming component 1 shown in FIG. 1a, but rotated 90-degrees about a longitudinal axis 29 running length-wise through the foaming component 1. Thus the bypass apertures 21 have been rotated so that only one can be seen in FIG. 1b, with the other 10 being out of view.

(19) The discharge stroke shall now be described in more detail with respect to FIGS. 2a to 2c. Certain reference signs have intentionally been omitted for the sake of clarity.

(20) Generally, the volumes of the liquid 3 and air 5 chambers are shown to progressively decrease from FIGS. 2a to 2c as the stationary section 7 and translatable section 9 are brought together, resulting in positive pressure in the chambers and thus liquid and air being ejected therefrom resulting in foamed liquid being dispensed from the dispensing aperture 17 of the foaming component 1.

(21) FIG. 2a shows the initiation of the discharge stroke in which the translatable section 9 of the foaming component 1 is pushed in the direction shown by the pair of vertical, upward pointing arrows into the stationary section. In this figure further arrows denote the resultant forcing of air from the air chamber 5, through the air channel 23, whereupon air is split such that one portion of the air is forced through the outer surface 13a of the sparging interface into liquid in the foaming region 15 and another portion of air is forced through the bypass aperture 21, into the air pocket 25, and finally forced through the inner surface 13b of the sparging interface. Thus as shown in the figure, air enters the foaming region 15 from both sides of the foaming region 15.

(22) FIG. 2b shows the foaming component 1 mid-way through the discharge stroke and includes arrows denoting the flow of liquid from the liquid chamber 3, through the liquid transfer valve 27 whereupon it enters into the foaming region 15 and is aerated by air passing through the sparging interface 13 as described above. The air that enters into both sides of the foaming region 15 forms bubbles in the liquid owing to it having passed through the sparging interface 13 which is provided with holes of a sufficiently small diameter to promote the formation of bubbles in the liquid as air is passed through. The small diameter of the holes also prevents any particles suspended in the liquid from entering into the air pocket 25. Positive pressure inside the pocket 25 also helps prevent entry of particles into the pocket 25.

(23) FIG. 2c shows the end of the discharge stroke. The volumes of the liquid 3 and air 5 chambers are at a minimum and no further foamed soap is dispensed.

(24) In a one-shot system, the foaming component would now be depleted. It could then be discarded, replaced or manually recharged. But in the majority of applications it is desirable that the foaming component is automatically recharged following the completion of the discharge stroke. This may be achieved by employing a spring mechanism that serves to resiliently bias the stationary 7 and translatable 9 sections apart, such that following release of an application of a force to discharge at the end of the discharge stroke, the sections are automatically brought together through the action of the spring mechanism, whereupon the recharge stroke commences.

(25) The recharge stroke shall now be described in more detail with respect to FIGS. 3a to 3c. Certain reference integers have again been omitted for the sake of clarity.

(26) Generally, the volumes of the liquid 3 and air 5 chambers are shown to progressively increase from FIGS. 3a to 3c as the stationary section 7 and translatable section 9 are moved apart, resulting in negative pressure in the chambers and thus liquid being sucked into the liquid chamber 3 and air being sucked into the air chamber 5.

(27) FIG. 3a shows the initiation of the recharge stroke in which the translatable section 9 is brought in a direction of separation from the stationary section 7 in the direction of the vertical, downward pointing arrows. This results in negative pressure in the air chamber 5 causing air to be sucked in from the outside, through the one-way air intake valve 19, and into the air chamber 5, in the direction shown by the arrows by the valve 19 in the figure. Employing the air intake valve 19 helps avoid residue foam from a previous discharge operation being sucked up into and potentially clogging the device.

(28) FIG. 3b shows the foaming component 1 mid-way through the recharge stroke and it is shown how liquid during the recharge stroke is sucked via negative pressure created inside the liquid chamber 3, from liquid outside the foaming component 1, through the one-way liquid intake valve 20, and into the liquid chamber 3 thereby to replenish the liquid chamber 3. The smaller arrows in the figure show the direction of travel of the liquid through the liquid intake valve 20.

(29) FIG. 3c shows the foaming component 1 at the point of completion of the recharge stroke. The liquid chamber 3 and air chamber 7 are fully replenished with liquid and air respectively, ready for a discharge stroke.

(30) Although the term recharge is used, it is to be considered that the same stroke could 5 be employed in order to prime the foaming component 1 before the first discharge stroke.

(31) In the example of FIGS. 4-6, there is provided an example of a fixed foaming component 1 having stationary section 7 and translatable section 9 which combine to form a liquid chamber 3 and an air chamber 5. Attached to the stationary section 7 there is provided a sparging component 11, comprising sparging interface 31. The foaming region 33 is disposed between opposing surfaces of the sparging interface 31. The foaming region 33 of this example comprises two zones, a first zone 33a and a second zone 33b. As can be seen, in particular from FIG. 6, the sparging interface 31 of the first zone 33a of the foaming region 33 comprises a radially outer surface 35a and a radially inner surface 35b. The sparging interface 31 of the second zone 33b of the foaming region 33 also comprises a radially outer surface 37a and a radially inner surface 37b. There is also provided two foaming conduits 39. As with the first example, both surfaces of the sparging interfaces 31 of the first 33a and second zones 33b of the foaming region 33 are annular in cross-section and co-centric.

(32) As with the first example, a one-way liquid intake valve 20 is present, allowing the liquid to be provided in replaceable cartridges. The one-way air intake valve 19 is also present in this example. Both intake valves 19, 20 function as described above for the first example.

(33) The operation of the foaming component 1 of this example is as follows. A charge of liquid is provided through intake valve 20, which closes when the liquid chamber 3 is full. The translatable section 9 is translated into the stationary section 7 effecting a compression of the liquid chamber 3 and the air chamber 5. Liquid is thus forced out of the liquid chamber 3, through a liquid transfer valve 27 into the first zone 33a of foaming region 33 and then through the foaming conduits 39 into the second zone 33b of foaming region 33. It will be appreciated that the structure of the foam will change as it flows from the first zone 33a of the foaming region 33 through the foaming conduits 39 to the second zone 33b of the foaming region 33 and to the exit aperture 17. Initially, the foam may be an aerated liquid, or a foam with large unstable bubbles, however, the turbulence applied to the foam as it passes through this tortuous flow path causes the bubbles in the foam to collapse, such that the foam contains multiple small bubbles. This provides a smooth stable foam. Foaming occurs as described above, through the forcing of air out of the air chamber 5 through the sparging component 11 and the resulting foam is dispensed through exit aperture 17.

(34) It should be appreciated that the processes and apparatus of the invention are capable of being implemented in a variety of ways, only a few of which have been illustrated and described above.