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Title:
APPARATUS FOR CONDITIONING A LIQUID, CARTRIDGE, AND CONTAINER
Document Type and Number:
WIPO Patent Application WO/2019/175603
Kind Code:
A1
Abstract:
Apparatus for conditioning a liquid is disclosed. In one arrangement, a flow system is provided that guides a flow of liquid under the force of gravity. A first conditioning unit modifies a composition of liquid flowing in the flow system through the first conditioning unit. The flow system divides liquid flowing in the flow system into at least a first sub-flow and a second sub-flow. The liquid in the first sub- flow is modified more than liquid in the second sub-flow by the first conditioning unit. A flow controller allows selective modification of a proportion of the flow of liquid in the flow system that is directed into the first sub-flow relative to the second sub-flow, thereby changing an overall modification of the composition of liquid by the apparatus.

Inventors:
COLONNA-DASHWOOD, Maxwell (Unit 5, Apollo ParkArmstrong Way, Yate Bristol BS37 5AH, BS37 5AH, GB)
MCCULLOUGH, Andrew (The Technology Centre, Framlingham Suffolk IP13 9EZ, IP13 9EZ, GB)
HENDON, Christopher H. (Paced Limited, The Print Rooms Unit 301164-180 Union Street, London Greater London SE1 0LH, SE1 0LH, GB)
Application Number:
GB2019/050741
Publication Date:
September 19, 2019
Filing Date:
March 15, 2019
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
PACED LIMITED (The Print Rooms, Unit 301164-180 Union Street, London Greater London SE1 0LH, SE1 0LH, GB)
International Classes:
C02F1/00; A47J31/06; A47J31/60; F16K11/06; C02F1/28; C02F1/42; C02F1/68; C02F101/10
Foreign References:
DE102008001635A12009-08-27
US20060032796A12006-02-16
EP2899164A12015-07-29
EP1106578A12001-06-13
TW201020217A2010-06-01
DE102006005780A12007-08-16
US20160244341A12016-08-25
Attorney, Agent or Firm:
J A KEMP (14 South Square, Gray's Inn, London Greater London WC1R 5JJ, WC1R 5JJ, GB)
Download PDF:
Claims:
CLAIMS

1. An apparatus for conditioning liquid, comprising:

a flow system configured to guide a flow of liquid under the force of gravity; and

a first conditioning unit configured to modify a composition of liquid flowing in the flow system through the first conditioning unit, wherein:

the flow system is configured to divide liquid flowing in the flow system into at least a first sub flow and a second sub-flow, wherein liquid in the first sub-flow is modified more than liquid in the second sub-flow by the first conditioning unit; and

a flow controller configured to allow selective modification of a proportion of the flow of liquid in the flow system that is directed into the first sub-flow relative to the second sub-flow, thereby changing an overall modification of the composition of liquid by the apparatus.

2. The apparatus of claim 1, wherein:

the flow system comprises a first outlet and a second outlet; and

the flow system is configured such that the first sub-flow leaves the flow system via the first outlet and the second sub-flow leaves the flow system via the second outlet.

3. The apparatus of claim 1 or 2, wherein the flow system is configured so that:

the first sub-flow flows along a first flow path and the second sub-flow flows along a second flow path; and

the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is achieved by changing a flow resistance of either or both of the first flow path and the second flow path.

4. The apparatus of claim 3, wherein the second flow path comprises flow through an orifice and the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is implemented by configuring the apparatus to allow a cross-sectional area of the orifice to be selectively modified.

5. The apparatus of claim 4, wherein the cross-sectional area of the orifice is selectively modified by changing a rotational position of a first opening relative to a second opening, an overlap between the first opening and the second opening defining the cross-sectional area of the orifice.

6. The apparatus of claim 5, wherein, relative to an axis of the rotation of the first opening, the first opening has a radial width that varies in a circumferential direction to provide a continuous modification of the cross-sectional area of the orifice as a function of rotational position of the first opening relative to the second opening.

7. The apparatus of claim 5 or 6, wherein:

the first opening is provided in a plate connected to a control stem having a longitudinal axis, the plate comprising one or more radial protrusions, each radial protrusion being configured to be insertable axially through a corresponding respective opening in an annular lip;

the annular lip is connected to a wall containing the second opening;

the radial protrusions and annular lip are configured such that subsequent rotation of the plate about the longitudinal axis brings one or more of the radial protrusions into engagement with a lower surface of the annular lip; and

the engagement is such as to force the plate having the first opening against the wall having the second opening to promote formation of a seal between the plate and the wall, the seal surrounding the orifice formed by the first opening and the second opening.

8. The apparatus of any preceding claim, wherein:

the first conditioning unit comprises a first reservoir containing a first liquid conditioning material; and

the apparatus further comprises a second conditioning unit comprising a second reservoir containing a second liquid conditioning material.

9. The apparatus of claim 8, wherein:

the second conditioning unit comprises an inlet tube configured to receive the second sub-flow, the second sub-flow entering the inlet tube at an upper end of the inlet tube and exiting the inlet tube into the second reservoir at a lower end of the inlet tube; and

a height in the inlet tube, or at the lower end of the inlet tube, where the second sub-flow first encounters the second liquid conditioning material is lower than an upper level of the second liquid conditioning material in the second reservoir.

10. The apparatus of claim 9, wherein the height in the inlet tube, or at the lower end of the inlet tube, where the second sub-flow first encounters the second liquid conditioning material is at least 10% of a height of an internal volume of the second reservoir below the upper level of the second liquid conditioning material in the second reservoir.

11. The apparatus of any of claims 8-10, wherein a level of the second liquid conditioning material where the second sub-flow first encounters the second liquid conditioning material when flowing downwards through the flow system is lower than the upper level of the first liquid conditioning material where the first sub-flow first encounters the first liquid conditioning material when flowing downwards through the flow system.

12. The apparatus of any of claims 8-11, wherein the first liquid conditioning material comprises an ion exchange material.

13. The apparatus of claim 12, wherein the ion exchange material comprises at least two different types of ion.

14. The apparatus of claim 12 or 13, wherein the first liquid conditioning material is configured to reduce a concentration of bicarbonates in liquid flowing through the first liquid conditioning material.

15. The apparatus of any of claims 8-14, wherein the second liquid conditioning material contains no ion exchange material.

16. The apparatus of any of claims 8-15, wherein either or both of the first liquid conditioning material and the second liquid conditioning material comprise activated carbon.

17. The apparatus of any of claims 8-16, wherein:

the first sub-flow passes through the first reservoir and not through the second reservoir; and the second sub-flow passes through the second reservoir and not through the first reservoir.

18. The apparatus of any of claims 8-17, wherein the first liquid conditioning material is held separated from the second liquid conditioning material.

19. A cartridge configured to be removably inserted into a container for holding liquid, wherein: the cartridge comprises the apparatus for conditioning liquid of any preceding claim, and is configured such that if liquid is provided in an upper region of the container the liquid can flow through the flow system of the apparatus to a lower region of the container.

20. A container for holding liquid comprising the apparatus of any of claims 1-18, configured such that if liquid is provided in an upper region of the container the liquid can flow through the flow system of the apparatus to a lower region of the container.

Description:
APPARATUS FOR CONDITIONING A LIQUID, CARTRIDGE, AND CONTAINER

The present disclosure relates to an apparatus for conditioning a liquid, particularly to an apparatus for conditioning drinking water in a domestic context to be used for brewing a beverage, particularly coffee.

It is known that drinking qualities of beverages such as tea and coffee can depend on the composition of water that is used to prepare them. Where a beverage is prepared in a professional setting, such as in a factory or coffee shop, it is economically feasible to use highly sophisticated filtering systems to tailor the composition of water to optimise the quality of the beverage. For a home user, however, such industrial systems are not appropriate.

It is known to provide filter cartridges which can be inserted into water jugs to improve the general quality of water in a domestic setting. Such cartridges are capable of improving tea and coffee, but only to a limited extent. It is also necessary to choose a particular type of filter cartridge depending on the nature (e.g. hardness) of tap water to be filtered, which can vary from region to region. It is difficult with such a system to adapt efficiently to day-to-day variations in tap water composition.

It is an object of the invention to provide an improved apparatus for conditioning a liquid which at least partially addresses one or more of the challenges mentioned above or other challenges.

According to an aspect of the invention, there is provided an apparatus for conditioning liquid, comprising: a flow system configured to guide a flow of liquid under the force of gravity; and a first conditioning unit configured to modify a composition of liquid flowing in the flow system through the first conditioning unit, wherein: the flow system is configured to divide liquid flowing in the flow system into at least a first sub-flow and a second sub-flow, wherein liquid in the first sub-flow is modified more than liquid in the second sub-flow by the first conditioning unit; and a flow controller configured to allow selective modification of a proportion of the flow of liquid in the flow system that is directed into the first sub-flow relative to the second sub-flow, thereby changing an overall modification of the composition of liquid by the apparatus.

Thus, an apparatus is provided which allows a liquid to be conditioned in a controllable and user- variable way using a simple, gravity fed mechanism. The apparatus is particularly well suited to improving a quality of water to use for brewing tea or coffee in a domestic context. The apparatus can be made compact and implemented at low cost. The ability to vary the conditioning allows a user to quickly tailor the output according to the composition of his or her local water supply and/or according to taste.

Furthermore, the control of the proportion of the liquid that passes through the first conditioning unit opens up new opportunities for efficiently using liquid conditioning materials that require longer contact times between the liquid and the liquid conditioning materials (e.g. longer times than are traditionally required in domestic water filtration apparatuses, such as water filter jugs for drinking water). Such longer times may be optimal, for example, where a complex liquid conditioning material containing multiple different ion exchange materials is used. The control varies not only the proportion of the liquid contacting the liquid conditioning material in the first conditioning unit but also the time it takes for liquid to flow through the flow system overall. The present approach thus provides multi dimensional and flexible tuning of the liquid conditioning. The approach is particularly applicable to applications where a finite fixed body of liquid is to be treated, such as a dose of liquid in an upper portion of a jug, as opposed to liquid being treated from a continuous source such as a mains supply where the control of timing will not apply in the same way.

In an embodiment, the flow system comprises a first outlet and a second outlet; and the flow system is configured such that the first sub-flow leaves the flow system via the first outlet and the second sub-flow leaves the flow system via the second outlet. Providing separate outlets for the two sub-flows provides a more efficient flow of liquid through the flow system and provides greater design freedom for controlling flow without risk of blockage or unpredictable flow patterns.

In an embodiment, the flow system is configured so that: the first sub-flow flows along a first flow path and the second sub-flow flows along a second flow path; and the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is achieved by changing a flow resistance of either or both of the first flow path and the second flow path. In an embodiment, the second flow path comprises flow through an orifice and the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is implemented by configuring the apparatus to allow a cross-sectional area of the orifice to be selectively modified. In an embodiment, the cross-sectional area of the orifice is selectively modified by changing a rotational position of a first opening relative to a second opening, an overlap between the first opening and the second opening defining the cross-sectional area of the orifice. In an embodiment, relative to an axis of the rotation of the first opening, the first opening has a radial width that varies in a circumferential direction to provide a continuous modification of the cross-sectional area of the orifice as a function of rotational position of the first opening relative to the second opening. This approach provides fine control of the division of flow into the first sub-flow and the second sub-flow in a reliable and easy to manufacture structure.

In an embodiment, the first opening is provided in a plate connected to a control stem having a longitudinal axis, the plate comprising one or more radial protrusions, each radial protrusion being configured to be insertable axially through a corresponding respective opening in an annular lip; the annular lip is connected to a wall containing the second opening; the radial protrusions and annular lip are configured such that subsequent rotation of the plate about the longitudinal axis brings one or more of the radial protrusions into engagement with a lower surface of the annular lip; and the engagement is such as to force the plate having the first opening against the wall having the second opening to promote formation of a seal between the plate and the wall, the seal surrounding the orifice formed by the first opening and the second opening. This approach provides a robust and easily manufactured sealing arrangement. When the apparatus is used to implement a filter cartridge in a jug, the approach allows quick and easy installation of multiple cartridges without changing the control stem.

In an embodiment, the first conditioning unit comprises a first reservoir containing a first liquid conditioning material; and the apparatus further comprises a second conditioning unit comprising a second reservoir containing a second liquid conditioning material. In an embodiment, the second conditioning unit comprises an inlet tube configured to receive the second sub-flow, the second sub-flow entering the inlet tube at an upper end of the inlet tube and exiting the inlet tube into the second reservoir at a lower end of the inlet tube; a height in the inlet tube, or at the lower end of the inlet tube, where the second sub-flow first encounters the second liquid conditioning material is lower than an upper level of the second liquid conditioning material in the second reservoir. This configuration increases a head height of liquid at the position where the liquid enters the second liquid conditioning material relative to the case where the inlet tube is absent. The increased head height increases the pressure and leads to quicker flow of liquid through the second reservoir, thereby enabling the second sub-flow to provide a more efficient bypassing role.

In an embodiment, an average flow direction of liquid in the first conditioning unit is oriented away from the vertical by at least 30°. Orienting the flow away from the vertical allows the apparatus to be made more compact in the vertical direction.

In an embodiment, the first conditioning unit comprises one or more flow disrupting members configured to induce a serpentine flow through the first conditioning unit. Creating a serpentine flow allows the first conditioning unit to be made more compact.

In an embodiment, a liquid conditioning material of the first conditioning unit is configured to reduce a concentration of bicarbonates in liquid flowing through the liquid conditioning material.

Adjusting the concentration of bicarbonates is particularly useful where the apparatus is used to provide water for brewing tea or coffee.

In an embodiment, the apparatus further comprising a second conditioning unit configured to modify a composition of liquid flowing in the flow system through the second conditioning unit. The provision of a second conditioning unit provides additional flexibility in how the liquid is conditioned.

In an embodiment, the first conditioning unit and the second conditioning unit are configured so that the first sub-flow and the second sub-flow are recombined with each other before exiting the second conditioning system. This facilitates manufacture by reducing the number of required outlets from the flow system.

In an embodiment, the first conditioning unit and the second conditioning unit are configured so that the first sub-flow and the second sub-flow do not mix with each other before both sub-flows have exited the second conditioning system. This facilitates optimal control of flow characteristics in the first and second sub-flows.

In an embodiment, a liquid conditioning material of the first conditioning unit is held separated from a liquid conditioning material of the second conditioning unit. This facilitates recycling of either or both of the liquid conditioning materials of the two conditioning units by avoiding irreversible mixing of the liquid conditioning materials.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which corresponding reference symbols indicate corresponding parts, and in which:

Figure 1 is a schematic side sectional view of a flow system of an apparatus for conditioning liquid according to an embodiment;

Figure 2 is a schematic top sectional view through a first conditioning unit of the flow system of Figure 1;

Figure 3 is a schematic top sectional view through a second conditioning unit of the flow system of Figure 1;

Figure 4 is a schematic side view of a flow controller according to an embodiment;

Figure 5 is a schematic side sectional view of a cartridge inserted into a container according to an embodiment;

Figure 6 is a side perspective cut-away view of a jug containing an apparatus for conditioning liquid according to a further embodiment;

Figure 7 is a side view of the jug of Figure 6;

Figure 8 is a side perspective cut-away view of a flow system installed in the jug of Figures 6 and 7;

Figure 9 is a side view of the flow system of Figure 8;

Figure 10 is a top perspective view of the jug of Figures 6-9 showing a control stem in a first rotational position;

Figure 11 is a top perspective view of the jug of Figures 6-10 showing a control stem in a second rotational position; and

Figure 12 is a schematic view of a plate containing a first opening that varies in width as a function of circumferential position. Embodiments of the present disclosure relate to an apparatus for conditioning liquid. Examples of such an apparatus are described below with reference to Figures 1-4. The apparatus may be embodied as a cartridge insertable into a container such as a jug. An example of such an embodiment is depicted in Figure 5.

In some embodiments, the liquid being conditioned is aqueous. The liquid may comprise, consist essentially of, or consist of, tap water for instance. As is well known, tap water consists mostly of water but also contains impurities, including acids and bicarbonates. Embodiments of the present disclosure aim to modify the composition of the water by changing the relative concentrations of impurities present in the water. In some embodiments, a concentration of bicarbonates is reduced, which can improve the drinking quality of beverages, particularly coffee, made using the conditioned liquid.

In some embodiments, as depicted in Figure 1, the apparatus comprises a flow system 1. The flow system 1 guides a flow of liquid (broken line arrows) under the force of gravity through the flow system 1 (i.e. the flow is driven by the force of gravity)

In an embodiment, the apparatus comprises a first conditioning unit 4. The first conditioning unit 4 modifies a composition of liquid flowing in the flow system 1 through the first conditioning unit 4. In the example of Figure 1, liquid enters the first conditioning unit 4 at inlet 11 and exits the first conditioning unit 4 at outlet 13. The first conditioning unit 4 may be configured to modify the composition of the liquid in various ways. In some embodiments, the first conditioning unit 4 reduces a concentration of one or more predetermined components of liquid. In some embodiments, the first conditioning unit 4 increases a concentration of one or more predetermined components of liquid.

In an embodiment, the apparatus further comprises a second conditioning unit 6. The second conditioning unit 6 modifies a composition of liquid flowing in the flow system 1 through the second conditioning unit 6. In the embodiment shown, the second conditioning unit 6 is provided in series with the first conditioning unit 4 with respect to at least the first sub-flow. In the example of Figure 1, liquid enters the second conditioning unit 6 at the outlet 13 from the first conditioning unit 4 and exits the second conditioning unit 6 at outlet 15.

In some embodiments, a liquid conditioning material 7 of the second conditioning unit 6 is different from a liquid conditioning material 5 of the first conditioning unit 5. For example, the liquid conditioning material 7 of the second conditioning unit 6 may modify a concentration of a target substance in liquid that is substantially not modified by the liquid conditioning material 5 of the first conditioning unit 4.

In an embodiment, the liquid conditioning material 5 of the first conditioning unit 4 comprises an ion exchange material. The ion exchange material may be configured to reduce a concentration of bicarbonates in liquid flowing through the liquid conditioning material 5. In an embodiment, the first conditioning unit 4 is configured (e.g. by virtue of its dimensions, the imposed flow path of liquid, the amount of the liquid conditioning material 5 through which liquid is forced to flow, and/or the composition of the liquid conditioning material 5) such that the reduction in the concentration of bicarbonates results in the ratio of the number of moles of bicarbonate to the number of moles of acid being less than 1:1 (i.e. less bicarbonate), optionally less than 1 :2, optionally less than 1 :5, optionally less than 1: 10, optionally less than 1:50, optionally less than 1:100. The number of moles of acid is herein understood to mean the number of moles of H + .

In an embodiment, the liquid conditioning material 7 of the second conditioning unit 6 comprises activated carbon.

In some embodiments, as shown in Figure 1, the liquid conditioning material 5 of the first conditioning unit 4 is held separated from the liquid conditioning material 7 of the second conditioning unit 6. Holding the liquid conditioning materials separated facilitates recycling of one or both of the liquid conditioning materials after use. This is because it avoids potentially irreversible mixing of the liquid conditioning materials.

In an embodiment, as depicted in Figures 1-3, the flow system 1 divides liquid flowing in the flow system 1 into at least a first sub-flow and a second sub-flow. The liquid in the first sub-flow is modified more than liquid in the second sub-flow by the first conditioning unit 4.

In an embodiment, a flow controller (e.g. a mechanism that allows the flow to be controlled) is provided that allows selective modification of a proportion of the flow of liquid in the flow system 1 that is directed into the first sub-flow relative to the second sub-flow. An overall modification of the composition of liquid by the apparatus can therefore be controlled.

In some embodiments, the flow system 1 is configured such that the first sub-flow flows through the first conditioning unit 4 to a greater extent than the second sub-flow. In some embodiments, at least 10%, optionally at least 25%, optionally at least 75%, optionally at least 90%, optionally at least 99%, optionally substantially all, of the second sub-flow completely bypasses the first conditioning unit 4. In the example of Figures 1-3, the first sub-flow flows through the first conditioning unit (entering at inlet 11 and exiting at outlet 13) while the second sub-flow completely bypasses the first conditioning unit (entering at inlet 12, passing along bypass channel 14, and exiting directly into the second conditioning unit 6).

Regardless of the extent to which each of the first sub-flow and the second sub-flow flow through the first conditioning unit 4, the second conditioning unit 6 may be configured to receive a relatively large proportion of the total flow of liquid through the flow system 1. For example, the second conditioning unit 6 may be configured such that at least 50%, optionally at least 75%, optionally at least 90%, optionally at least 99%, optionally substantially all, of the flow of liquid through the flow system 1 flows through the second conditioning unit 6.

In some embodiments, as depicted in Figures 1-3, the first conditioning unit 4 and the second conditioning unit 6 are configured so that the first sub-flow and the second sub-flow are recombined with each other before exiting the second conditioning system 6. In the example of Figures 1-3, the second sub-flow recombines with the first sub-flow when it exits the bypass channel 14 and flows into the second conditioning unit 6. This arrangement is advantageous because it allows the outlet 15 to be a common outlet for both flows (i.e. for the first sub-flow and the second sub-flow). Fewer outlets therefore need to be provided in comparison with alternative arrangements in which separate outlets are provided for each of the first sub-flow and the second sub-flow.

In alternative embodiments, the first conditioning unit 4 and the second conditioning unit 6 are configured so that the first sub-flow and the second sub-flow do not mix with each other before both sub flows have exited the second conditioning system 6 (e.g. the first sub-flow and the second sub-flow flow separately through respective portions of the second conditioning system 6). This approach may allow the flow properties of the first sub-flow and the second sub-flow to be optimised more easily, which may for example decrease the amount of time that is necessary for all of the liquid to be conditioned to flow through the flow system 1.

Embodiments are not limited to comprising only two conditioning units (e.g. the first conditioning unit 4 and the second conditioning unit 6). In some embodiments, one or more further conditioning units are provided, each further conditioning unit comprising a liquid conditioning material that is different in some way to the liquid condition material provided in at least one other conditioning unit (optionally all of the other conditioning units).

In some embodiments, the apparatus is configured so that an average flow direction of liquid in the first conditioning unit 4 (and, optionally, where provided, in the second conditioning unit 6 or in any further conditioning unit) is oriented away from the vertical by at least 30°, optionally by at least 45°, optionally by at least 60°, optionally by at least 75°, optionally by 90° + 20°. In the particular example shown in Figure 1-3, the average flow direction of liquid in the first conditioning unit 4 and in the second conditioning unit 6 is substantially horizontal (i.e. at 90° degrees to the vertical).

Orienting the average flow direction away from the vertical allows the first conditioning unit and the second conditioning unit to be more compact in the vertical direction. Liquid conditioning materials through which the liquid needs to flow to be conditioned can be spread out more in the horizontal direction and/or the rate of flow can be reduced (thereby allowing the liquid to contact the liquid exchange materials for a longer period of time for the same flow length). Alternatively or additionally, the liquid can be made to flow in a serpentine path through the liquid conditioning materials (i.e. through the first conditioning unit 4 and/or through the second conditioning unit 6). In some embodiments, the serpentine flow is induced via one or more flow disrupting members such as baffles or other flow obstacles. In the example of Figures 1-3, as shown in Figures 2 and 3, baffles 20 and 21 are provided as flow disrupting members for inducing a serpentine flow through both of the first conditioning unit 4 and the second conditioning unit 6. The serpentine flow also helps to improve compactness of the apparatus by promoting efficient contact between the liquid and a large proportion of the liquid conditioning material present (filamentary flows through the liquid conditioning material, which may cause regions of the liquid conditioning material not to be fully contacted by the liquid, are reduced). The serpentine flow may also improve the consistency of the liquid conditioning by making the contact with the liquid conditioning material more consistent/reproducible.

The apparatus as a whole can thus be made more compact. When the apparatus forms part of a cartridge for insertion into a container for liquid (e.g. a jug), the vertical height of the jug can be reduced and/or more liquid can be stored and/or conditioned in the jug for a given height of jug.

In some embodiments, the flow system is configured so that the first sub-flow flows along a first flow path and the second sub-flow flows along a second flow path, and the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is achieved by changing a flow resistance of either or both of the first flow path and the second flow path. In an embodiment, an example of which is depicted in Figure 4, this is achieved by arranging for the second flow path to flow through an orifice 31-33 and the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is implemented by configuring the apparatus to allow a cross-sectional area of the orifice 31-33 to be selectively modified. There are many ways this could be achieved. For example, a moveable blocking member may be provided that can be progressively moved to block an orifice. In the example of Figure 4, a rotatable member 30 is provided that engages with an upper surface of the flow system 1. The rotatable member 30 is positioned over the inlet 12 to the bypass channel 14 but does not interfere with the inlet 11 into the first conditioning unit 4 (which is to the right beyond the range of Figure 4). In the example shown, the engagement is provided by cooperation between a cylindrical protrusion 34 from the flow system 1 and a circular indentation 36 in the rotatable member 30, but various other connection mechanisms may be used. When the rotatable member 30 is engaged against the flow system 1, a series of orifices 31-33 can be selectively brought into position above the inlet 12 into the bypass channel 14 of the flow system 1 by rotating the rotatable member 30 about a vertical axis. Each of the series of orifices 31-33 has a different cross-sectional area, so selection of the orifice to align with the inlet 12 defines the size of an orifice in the second flow path. By selecting a relatively large orifice (e.g. orifice 33), the relative proportion of the liquid flowing in the second sub-flow can be increased, thereby providing a lower overall modification of the liquid flowing through the apparatus by the first conditioning unit 4. By choosing a smaller orifice (e.g. orifice 32 or 31), or even blocking the inlet 12 by arranging for no orifice to communicate with the inlet 12 from the upstream side, the relative proportion of the liquid flowing in the second sub-flow can be decreased or suppressed entirely, thereby providing a higher overall modification of the liquid flowing through the apparatus by the first conditioning unit 4.

The provision of discrete orifices 31-33 allows the flow to be modified in corresponding discrete steps. This may be convenient for a user as it is more easily understandable. In other embodiments, however, continuous modification of the flow may be allowed, for example by providing a

circumferentially aligned opening having a radial width that varies along the circumference, instead of or in addition to the discrete orifices. When the apparatus forms part of a cartridge for insertion into a container for liquid (e.g. a jug), the rotatable member 30 may be configured so that it can be rotated manually or electrically by a user.

Figure 5 schematically depicts a typical context in which embodiments of the present disclosure may be used. The flow system 1 is provided in the form of a cartridge for insertion into a container 40 for holding liquid. In this embodiment, the container 40 is a jug for holding water. The flow system 1 can be inserted into a cartridge receiving structure 42 which holds the flow system 1 removably in place during use. A rotatable member 30 such as is depicted in Figure 4 may be provided for controlling the distribution of flow of liquid between the first sub-flow and the second sub-flow as discussed above. A rotation transmission system is provided to allow a user to rotate the rotatable element 30, for example via a rotatable knob 50 provided in a lid 48 of the container. The apparatus for conditioning liquid is configured such that if liquid is provided in an upper region 44 of the container 40 the liquid can flow through the flow system 1 of the apparatus to a lower region 46 of the container. The upper region 44 thus contains unconditioned liquid and the lower region 46 contains conditioned liquid. The conditioned liquid in the lower region 46 can be poured via a spout into a recipient to be used for preparing a beverage (e.g. a coffee machine reservoir).

Figures 6-12 depict a further embodiment in which the flow system 1 is provided in the form of a cartridge removably inserted into a container 40. The container 40 in this example is a jug. The jug comprises a handle 62 for holding the jug. The jug comprises a spout 64 through which liquid can be poured out of the jug after the liquid has been conditioned by flowing through the flow system 1 from an upper region 44 of the jug to a lower region of the jug 46.

The cartridge comprises a first conditioning unit 4 and a second conditioning unit 6. In the present embodiment, the first conditioning unit 4 comprises a first reservoir 73. The first reservoir 73 contains a first liquid conditioning material 5. The second conditioning unit 6 comprises a second reservoir 74. The second reservoir 74 contains a second liquid conditioning material 7. In the embodiment shown, the dividing of the flow into the first sub-flow and the second sub flow is implemented by a portion of the liquid in the upper region 44 passing into the first reservoir 73 via a plurality of first reservoir inlets 75 and thereby becoming the first sub-flow and another portion of the liquid in the upper region 44 passing into the second reservoir 74 via an orifice 80 (discussed in further detail below with reference to Figures 10-12) and thereby becoming the second sub-flow. The first sub flow passes through the first reservoir 73 and not through the second reservoir 74. The second sub-flow passes through the second reservoir 74 and not through the first reservoir 73. The first liquid conditioning material 5 is held separated from the second liquid conditioning material 7.

In this embodiment, the flow system 1 comprises a first outlet 71 and a second outlet 72. The first sub-flow flows along a first flow path through the first reservoir 73 and leaves the flow system 1 via the first outlet 71. The second sub-flow flows along a second flow path through the second reservoir 74 and leaves the flow system 1 via the second outlet 72. In this embodiment, from the point where the flow is divided into the first sub-flow and the second sub-flow to the exiting of the first sub-flow via the first outlet 71 and of the second sub-flow via second outlet 72, the first sub-flow is isolated from the second sub-flow. The first sub-flow does not therefore mix with the second sub-flow within the flow system 1. Liquid from the first sub-flow only mixes with liquid from the second sub-flow after the liquid has left the flow system 1 (i.e. after exiting through the first outlet 71 and the second outlet 72).

The selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is achieved by changing a flow resistance of either or both of the first flow path and the second flow path. In an embodiment of the type shown in Figures 6-12, the selective modification is achieved by changing a flow resistance in the second flow path. In an embodiment, this is achieved by arranging for the second flow path to comprise flow through the orifice 80 and providing a mechanism to allow a cross-sectional area of the orifice 80 to be selectively modified.

In an embodiment, the cross-sectional area of the orifice 80 is selectively modified by changing a rotational position of a first opening 81 relative to a second opening 82. Examples of the first opening 81 and the second opening 82 are depicted and labelled in Figures 8-12. In the embodiment shown, the first opening 81 is provided in a plate 84. The plate 84 is connected to a control stem 86 having a longitudinal axis X (depicted schematically in Figure 7). The control stem 86 is an elongate member extending from the plate 84 to a knob 50. The knob 50, the control stem 86 and the plate 84 are rigidly connected to each other and mounted to the container 40 in such a way as to be rotatable about the longitudinal axis X (e.g. by a user gripping and turning the knob 50).

Rotation of the plate 84 about axis X changes an overlap between the first opening 81 and the second opening 82. The degree of overlap defines the cross-sectional area of the orifice 80. Rotating the knob 50 can thus control the cross-sectional area of the orifice 80 and thereby control (selectively modify) the proportion of the flow directed into the first sub-flow relative to the second sub-flow.

Figures 8 and 9 depict a state in which the orifice 80 is completely closed because there is no overlap between the first opening 81 and the second opening 82.

Figure 10 depicts a rotational position of the first opening 81 in which only a narrow tail of the first opening 81 is aligned with the second opening 82, meaning the orifice 80 is open to a minimal extent. This rotational position of the first opening 81 corresponds to a state in which a relatively low proportion of the flow will be diverted into the second sub-flow. Figure 11 depicts a rotational position in which a widest part of the first opening 81 is aligned with the second opening 82. This rotational position of the first opening 81 corresponds to a state in which a relatively high proportion of the flow will be diverted into the second sub-flow.

As depicted in an exemplary manner in Figure 12, in some embodiments the first opening 81 has a radial width W1-W3 that varies in a circumferential direction to provide a continuous modification of the cross-sectional area of the orifice 80 as a function of rotational position of the first opening 81 relative to the second opening 82. The circumferential direction is here defined relative to the longitudinal axis X of the control stem 86. Starting at circumferential position A in Figure 12 and moving along the broken line in the direction of arrow 90 it can be seen that the radial width (the width in a direction perpendicular to the circumferential direction), continuously increases until about circumferential position B before continuously decreasing again to circumferentially position C.

In an embodiment, the radial width of the first opening 81 varies for at least 50% of the circumferential length of the first opening 81 (e.g. the distance along the broken line from A to C in the example of Figure 12). In some embodiments this variation is linear for at least a portion of the circumferential length. In other embodiments, the variation is non-linear for some or all of the circumferential length. In an embodiment, a rate of change of the rate of increase of the radial width of the first opening 81 with circumferential position, in a circumferential direction of increasing radial width (i.e. in the direction of arrow 90 for the range of circumferential positions between A and B in Figure 12), is positive for at least 25% of the circumferential length of the first opening 81, optionally for at least 50% of the circumferential length of the first opening 81, optionally for at least 75% of the circumferential length of the first opening 81. In an embodiment, the second opening 82 is circular but other shapes which do not extend excessively along the circumferential direction may be used. The inventors have found that configuring the first opening 81 and the second opening 82 in the manners described above provide particularly effective control of the division of flow into the first sub-flow and the second sub flow. In some embodiments, as visible most clearly in Figures 8-11 of the example shown, the plate 84 comprises one or more radial protrusions 92. Each protrusion 92 is insertable axially (e.g. in a direction parallel to the axis X of rotation of the control stem 86) and through a corresponding opening 98 (see Figures 10 and 11 for example) in an annular lip 94. The annular lip is connected to a wall 95 containing the second opening 82. The radial protrusions 92 and annular lip 94 are configured such that subsequent rotation of the plate 84 about the longitudinal axis X brings one or more of the radial protrusions 92 into engagement with a lower surface 96 of the annular lip 94 (see Figures 8 and 9). The engagement is such as to force the plate 84 having the first opening 81 against the wall 95 having the second opening 82 to promote formation of a seal between the plate 84 and the wall 95. The seal surrounds the orifice 80 formed by the first opening 81 and the second opening 82. This approach provides a robust and easily manufactured sealing arrangement, while also allowing quick and easy installation of multiple cartridges without changing the control stem 86.

In a further class of embodiment, of which the arrangement of Figures 6-12 is an example, the second conditioning unit 6 comprises an inlet tube 100. The inlet tube 100 receives the second sub-flow into the second reservoir 74. The second sub-flow enters the inlet tube 100 at an upper end of the inlet tube 100 (which in the example shown forms the second opening 82). The second sub-flow exits the inlet tube 100 into the second reservoir 74 at a lower end 101 of the inlet tube 100. A height in the inlet tube 100, or at the lower end 101 of the inlet tube 100, where the second sub-flow first encounters the second liquid conditioning material 7 (which may happen in the inlet tube 100 where the second liquid conditioning material 7 is present part way up the inlet tube 100 or may only happen at the lower end 101 of the inlet tube 100 where the second liquid conditioning material 7 does not enter the inlet tube at all) is lower than an upper level of the second liquid conditioning material 7 in the second reservoir 74. This configuration increases a head height of liquid at the position where the liquid enters the second liquid conditioning material 7 relative to the case where the inlet tube 100 is absent. The increased head height increases the pressure and leads to quicker flow of liquid through the second reservoir 74, thereby enabling the second sub-flow to provide a more efficient bypassing role. Capillary action means that second liquid conditioning material 7 that is above the lower end 101 of the inlet tube 100 (outside of the inlet tube 100) still contributes to conditioning of the second sub-flow in the second reservoir 74 (i.e. it is still wetted by the liquid). In an embodiment, a mesh or other mechanism is provided for preventing movement of the second liquid conditioning material 7 upwards into the inlet tube 100. A mesh may be provided, for example, at the lower end 101 of the inlet tube 100.

In an embodiment, the height in the inlet tube 100, or at the lower end 101 of the inlet tube 100, where the second sub-flow first encounters the second liquid conditioning material is at least 10%, optionally at least 20%, optionally at least 30%, of a height H of an internal volume of the second reservoir 74 (see Figure 7) below the upper level of the second liquid conditioning material 7 in the second reservoir 74 (e.g. when the second reservoir 74 is filled entirely with second liquid conditioning material 7, the inlet tube 100 would extend down to at least 10% of the second reservoir height H below the top of the second reservoir 74). In an embodiment, the height in the inlet tube 100, or at the lower end 101 of the inlet tube 100, where the second sub-flow first encounters the second liquid conditioning material 7 is less than 60%, optionally less than 50%, of the height H below the upper level of the second liquid conditioning material 7 in the second reservoir 74. If the lower end 101 of the inlet tube 100 is too low, the second liquid conditioning material 7 may not all be effectively wetted by the second sub-flow of liquid.

In an embodiment, a level of the second liquid conditioning material 7 where the second sub-flow first encounters the second liquid conditioning material 7 when flowing downwards through the flow system 1 is lower than the upper level of the first liquid conditioning material 5 where the first sub-flow first encounters the first liquid conditioning material 5 when flowing downwards through the flow system 1. This arrangement ensures that average head height generated pressure of liquid in the second liquid conditioning material 7 is higher than in the first liquid conditioning material 5, thereby favouring the second sub-flow providing an efficient bypassing role.

The first liquid conditioning material 5 may be formulated and/or configured to operate in any of the ways described above for the“liquid conditioning material 5 of the first conditioning unit 4” with reference to Figures 1-5. The first liquid conditioning material 5 may thus comprise an ion exchange material. The first liquid conditioning material 5 may reduce a concentration of bicarbonates in liquid flowing through the first liquid conditioning material 5. In an embodiment, the ion exchange material comprises at least two different types of ion. In an embodiment, the different types of ion comprises both cations and anions. In an embodiment, the ion exchange material comprises both alkaline and acidic resins. In an embodiment, the first liquid conditioning material 5 further comprises activated carbon.

The second liquid conditioning material 7 may be formulated and/or configured to operate in any of the ways described above for the“liquid conditioning material 7 of the second conditioning unit 6” with reference to Figures 1-5. The second liquid conditioning material 7 may thus comprise activated carbon. In an embodiment, the second liquid conditioning material 7 contains no ion exchange material.

In an embodiment, the first outlet 71 and the second outlet 72 are each connected to a sump arrangement to avoid drying out of activated carbon (or other materials) in the respective first and second reservoirs 73, 74. As shown in Figures 8 and 9, in the case of the first outlet 71, the first sub-flow is arranged to leave the first reservoir 73 by flowing through multiple small holes 111 in a lower wall 112 of the first reservoir 73 into a region between the lower wall 112 and an outer casing 113 of the flow system 1. The first sub-flow then moves laterally and rises up and over a first raised sump member 114 before exiting through the outlet 71. The first raised sump member 114 causes a level of liquid to remain continuously within the first reservoir 73 above the lower wall 112 of the first reservoir 73 up to a level corresponding to the height of the first raised sump member 114 (after a first use of the flow system 1), thereby ensuring that the first liquid conditioning material 5 stays humid. In the case of the second outlet 72, the second sub-flow is arranged to leave the second reservoir 74 by flowing through multiple larger holes 121 (relative to holes 111 of the first reservoir 73) in a lower wall 122 of the second reservoir 74 into a region between the lower wall 122 and the outer casing 113 of the first flow system 1. The second sub-flow then moves laterally and rises up and over a second raised sump member 124 before exiting through the outlet 72. The second raised sump member 124 causes a level of liquid to remain continuously within the second reservoir 74 above the lower wall 122 of the second reservoir 74 up to a level corresponding to the height of the second raised sump member 124 (after a first use of the flow system 1), thereby ensuring that the second liquid conditioning material 5 stays humid.

Further embodiments are described in the following numbered clauses:

1. An apparatus for conditioning liquid, comprising:

a flow system configured to guide a flow of liquid under the force of gravity; and

a first conditioning unit configured to modify a composition of liquid flowing in the flow system through the first conditioning unit, wherein:

the flow system is configured to divide liquid flowing in the flow system into at least a first sub flow and a second sub-flow, wherein liquid in the first sub-flow is modified more than liquid in the second sub-flow by the first conditioning unit; and

a flow controller configured to allow selective modification of a proportion of the flow of liquid in the flow system that is directed into the first sub-flow relative to the second sub-flow, thereby changing an overall modification of the composition of liquid by the apparatus.

2. The apparatus of clauses 1, wherein the first conditioning unit is configured to reduce a concentration of one or more predetermined components of liquid flowing through the first conditioning unit.

3. The apparatus of clause 1 or 2, wherein the first conditioning unit is configured to increase a concentration of one or more predetermined components of liquid flowing through the first conditioning unit.

4. The apparatus of any of clauses 1-3, configured such that in use an average flow direction of liquid in the first conditioning unit is oriented away from the vertical by at least 30°.

5. The apparatus of clause 4, wherein the average flow direction of liquid in the first conditioning unit is substantially horizontal. 6. The apparatus of any of clauses 1-5, wherein the first conditioning unit comprises one or more flow disrupting members configured to induce a serpentine flow through the first conditioning unit.

7. The apparatus of any of clauses 1-6, wherein a liquid conditioning material of the first conditioning unit comprises an ion exchange material.

8. The apparatus of any of clauses 1-7, wherein a liquid conditioning material of the first conditioning unit is configured to reduce a concentration of bicarbonates in liquid flowing through the liquid conditioning material.

9. The apparatus of clause 7 or 8, wherein the first conditioning unit is configured such that the reduction in the concentration of bicarbonates results in the ratio of the number of moles of bicarbonate to the number of moles of acid being less than 1 :1.

10. The apparatus of clause 9, wherein the first conditioning unit is configured such that the reduction in the concentration of bicarbonates results in the ratio of the number of moles of bicarbonate to the number of moles of acid being less than 1:10.

11. The apparatus of any of clauses 1-10, wherein the flow system is configured such that at least 10% of the second sub-flow completely bypasses the first conditioning unit.

12. The apparatus of any of clauses 1-11, wherein the flow system is configured such that at least 90% of the second sub-flow completely bypasses the first conditioning unit.

13. The apparatus of any of clauses 1-12, wherein the apparatus further comprising a second conditioning unit configured to modify a composition of liquid flowing in the flow system through the second conditioning unit.

14. The apparatus of clause 13, wherein the second conditioning unit is provided in series with the first conditioning unit with respect to at least the first sub-flow.

15. The apparatus of clause 13 or 14, wherein the second conditioning unit is configured such that at least 90% of the flow of liquid through the flow system flows through the second conditioning unit.

16. The apparatus of clause 15, wherein the first conditioning unit and the second conditioning unit are configured so that the first sub-flow and the second sub-flow are recombined with each other before exiting the second conditioning system.

17. The apparatus of clause 15, wherein the first conditioning unit and the second conditioning unit are configured so that the first sub-flow and the second sub-flow do not mix with each other before both sub-flows have exited the second conditioning system.

18. The apparatus of any of clauses 13-17, wherein a liquid conditioning material of the second conditioning unit is different from a liquid conditioning material of the first conditioning unit. 19. The apparatus of clause 18, wherein the liquid conditioning material of the second conditioning unit is configured to modify a concentration of a target substance in liquid that is substantially not modified by the liquid conditioning material of the first conditioning unit.

20. The apparatus of clause 18 or 19, wherein the liquid conditioning material of the second conditioning unit comprises activated carbon.

21. The apparatus of any of clauses 13-20, wherein a liquid conditioning material of the first conditioning unit is held separated from a liquid conditioning material of the second conditioning unit.

22. The apparatus of any of clauses 1-21, wherein the flow system is configured so that:

the first sub-flow flows along a first flow path and the second sub-flow flows along a second flow path; and

the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is achieved by changing a flow resistance of either or both of the first flow path and the second flow path.

23. The apparatus of clause 22, wherein the second flow path comprises flow through an orifice and the selective modification of the proportion of the flow directed into the first sub-flow relative to the second sub-flow is implemented by configuring the apparatus to allow a cross-sectional area of the orifice to be selectively modified.

24. A cartridge configured to be removably inserted into a container for holding liquid, wherein: the cartridge comprises the apparatus for conditioning liquid of any preceding claim, and is configured such that if liquid is provided in an upper region of the container the liquid can flow through the flow system of the apparatus to a lower region of the container.

25. A container for holding liquid comprising the apparatus of any of clauses 1-23, configured such that if liquid is provided in an upper region of the container the liquid can flow through the flow system of the apparatus to a lower region of the container.