WO2006003353A1

WO2006003353A1 - Liquid treatment filter

Info

Publication number: WO2006003353A1
Application number: PCT/GB2004/002901
Authority: WO
Inventors: Lee Lovelace
Original assignee: Morphy Richards Limited
Priority date: 2004-07-02
Filing date: 2004-07-02
Publication date: 2006-01-12

Abstract

A liquid treatment filter (180, 1400) comprising a chamber (210, 211, 1407) for housing a filter material, an inlet (205, 1402) to control the flow of liquid through the filter and an outlet (200, 1401, 1502). The liquid treatment filter further comprises an inner dividing wall or insert configured to deflect the flow of liquid between the inlet and outlet. The internal flow deflection means is configured to extend the contact time between the liquid and filter material providing a compact filter cartridge.

Description

LIQUID TREATMENT FILTER

Field of the Invention

The present invention relates to a liquid treatment filter and in particular, 5 although not exclusively, to a filter configured to provide a plurality of liquid flow paths through the filter so as to extend the contact time between the liquid and the liquid treatment material within the filter.

Background to the Invention o Water treatment filters have been used for some years, particularly in the treatment of household tap water. Typically, such filters for use in the home comprise a granular ion exchange resin and/or activated charcoal which function to remove minerals and chloride from the water prior to consumption.

5 A common liquid treatment filter, found in the art, comprises a generally cylindrical body provided with an inlet at one end of the cylinder to allow a flow of liquid into an inner chamber housing the filter material and an outlet provided at an adjacent end to allow a flow of liquid out of the chamber. Typically, the filter cartridge is positioned within a water filter jug at a mid-point therein separating an o upper non-treated water storage compartment and a lower treated water storage compartment. Examples of such liquid treatment filters are disclosed in WO 98/32705, GB 2269586, WO 98/17582, WO 98/05401 , US 3747767 and EP 0992458.

5 Common to such known liquid treatment filters is the use of a mesh or similar woven grating positioned at the outlet and configured to prevent loss of the granular filter material from the inner chamber. Water flows under gravity, from the inlet to the outlet in direct contact with the granular liquid treatment material. In some examples, the mesh extends across substantially the whole of o the cylindrical base section. Other examples include the separate locating of a mesh over separate orifices provided at the base of the cylinder so as to provide a plurality of independent mesh covered outlets.

Typically, the granular liquid treatment medium is stored within a single 5 chamber between the inlet and outlet. This particular configuration is disadvantages for a number of reasons.

One considerable disadvantage with known liquid treatment filters is the tendency for the outlet to become blocked by the granular filter material following o only short or moderate periods of use.

The clogging of the outlet results from the force exerted by the moist granulate material in the region of the outlet. The inventors have realised two mechanisms by which the outlet becomes clogged firstly, the material may be 5 compacted under its own weight at the bottom of the chamber and secondly the structure of the outlet may deform in response to the weight of the compacted, moist filter material. With conventional filters, the inventors have observed blockage of the outlet following the processing of as little as 10 litres of liquid. Prior to blockage, the amount of time taken to process 1 litre of liquid increases o from anywhere up to 10 to 15 mins.

A further problem exists with typical prior art filter devices in that the filter material is housed within a single chamber whereby the liquid flows from the inlet to the outlet via a single flow path. In order to provide sufficient contact between 5 the liquid and the treatment material within the filter conventional devices are generally large in size particularly with regard to cartridge length. So as to accommodate a bulky liquid treatment cartridge within a conventional water jug the volume available for pre and post treated water within the water jug must be compromised. The user is therefore disadvantaged with respect to the amount of o available filtered water for a given size of filter jug. What is required therefore is a filter device of compact construction configured with an outlet that is resistant to clogging whilst providing an extended contact time between the liquid and filter material.

Summary of the Invention

A liquid treatment filter device is provided of relatively compact construction comprising at least one outlet configured to be resistant to blocking by the filter material and at least one liquid flow deflection means within the chamber housing the filter material configured to extend the time of contact between the liquid and the filter material.

The liquid flow rate according to a specific implementation is controlled by a cross-sectional area of the inlet, the multiplicity, size and relative positioning of the liquid flow deflection means within the chamber and optionally a cross- sectional area of the outlet. In certain specific embodiments, the liquid flow deflection means comprises at least one or a plurality of internal chamber walls defining a plurality of channels or internal sub-chambers configured to house the filter material so as to provide a network or labyrinth of internal channels or chambers through which the liquid must flow between the inlet and outlet. Such a configuration provides for an extended time of contact between the liquid and the filter material and importantly avoids excessive force placed on the outlet created by the weight of the moist, granular filter material.

According to a specific implementation the liquid flowing through the filter between the inlet and outlet is forced to follow a plurality of different flow path directions so as to maximise efficient use of the filter chamber size. The shape and relative positioning of the internal chamber or channel walls may provide for a liquid flow path both under and against gravity. Accordingly in one specific embodiment, a filter is provided with liquid flow deflection means provided within the internal chamber configured to provide a first liquid flow path against gravity and a second liquid flow path under gravity. -A-

According to a first aspect of the present invention there is provided a liquid treatment filter comprising: at least one chamber being defined by an outer chamber wall, said chamber capable of housing a liquid treatment medium; at least one inlet configured to allow a flow of a liquid into said at least one chamber; at least one outlet configured to allow a flow of said liquid out of said at least one chamber; said filter further comprising and characterised by: at least one inner channel wall positioned within said at least one chamber, said at least one channel wall being configured to guide the flow of said liquid from said inlet to said outlet in a plurality of different flow directions; wherein a liquid flow path within said filter is extended by said at least one channel wall.

The channel wall may comprise a plurality of walls positioned within the chamber so as to form a network of channels through which the liquid flows. Alternatively, the chamber may be divided into a plurality of inter-linked chambers through which the liquid flows, in particular two inner sub-chambers being defined by a single inner channel wall and an exterior wall of the filter cartridge, the channel wall comprising at least one orifice configured to allow the flow of liquid from a first chamber into a second chamber as the liquid flows from the inlet to the outlet.

The chamber configured to house the liquid treatment material is defined by an outer chamber wall which may be formed integrally or non-integrally with the at least one channel or chamber wall positioned within the chamber. Additionally, the filter may further comprise a filter cap configured for releasably affixing to the chamber so as to provide a seal for the filter enclosing the liquid treatment material. The cap may comprise a projection extending into the chamber, the inlet being positioned substantially at one end of the projection as a plurality of orifices or slits, the size or cross-sectional area of which being configured to control the flow of the liquid into the filter.

According to a second aspect of the present invention there is provided a liquid treatment filter comprising: a main body defining a chamber capable of housing a liquid treatment medium; at least one inlet configured to allow a flow of a liquid into said chamber; at least one outlet configured to allow a flow of said liquid out of said chamber; said filter further comprising and characterised by: at least one internal chamber wall dividing said chamber into a plurality of sub- chambers; wherein said filter is configured to allow a flow of said liquid from said inlet to said outlet through said plurality of sub-chambers involving at least one direction change of the flow of said liquid through said filter.

Preferably, the internal chamber wall comprises a plurality of orifices configured to allow the flow of liquid between the sub-chambers. According to a specific implementation, the inlet is provided at a first sub-chamber and the outlet is provided at a further sub-chamber, both the inlet and/or the outlet being in direct contact with the liquid treatment medium, the plurality of sub-chambers being capable of housing the liquid treatment medium.

The outlet may comprise a plurality of slits being defined by a plurality of ribs or elongate members arranged in a step-like configuration, the outlet being provided at a base region of the main body of the filter. Additionally, the outlet may be formed as at least one projection extending from the outer chamber walls or base section of the filter body into the chamber. The slits, forming the outlet, may also extend from the chamber walls or base section into the chamber.

According to a specific implementation, the chamber is divided into a inner sub-chamber and an annular sub-chamber the inlet being provided at the inner sub-chamber and the outlet being provided at the annular outer sub-chamber.

According to a third aspect of the present invention there is provided a liquid treatment filter comprising: a main body defining a chamber capable of housing a granulate filter material; an inlet configured to allow a flow of a liquid into said chamber; an outlet configured to allow a flow of said liquid out of said chamber; said filter further comprising and characterised by: at least one inner chamber wall being housed within said chamber, said inner chamber wall defining a first sub-chamber and a second sub-chamber; at least one orifice formed within said inner chamber wall; wherein said inlet is provided at said first sub-chamber and said outlet is provided at said second sub-chamber, said filter being configurable to allow a flow of said liquid from said inlet to said outlet via said first sub- 5 chamber and said second sub-chamber.

A cross sectional width of the at least one projection may decrease away from the chamber wall or base section into the chamber whereby at least one face of the at least one projection is tapered or sloping into the chamber. The o orifices or slits of the outlet are formed on the at least one face whereby clogging of the outlet is inhibited as the granular filter material is configured to cascade down the sloping faces. The orifices or slits of the outlet may be bordered by ridges or ribs which also serve to inhibit deposition of the moist granular filter material at the outlet. 5

Where the inner chamber is divided into a first sub-chamber and a second sub-chamber, the at least one insert defining the sub-chambers is configured to deflect the flow of liquid through the filter so as to provide a liquid flow in a first direction and a liquid flow in a second direction being substantially transverse to o one another.

Preferably, the filter further comprises a mesh substantially enclosing the outlet configured to prevent loss of a carbon based filter material.

5 According to a fourth aspect of the present invention there is provided a water treatment filter cartridge comprising: a main body defining a chamber configured to house a granular water filter material; at least one inlet capable of allowing a flow of water into said chamber; at least one outlet capable of allowing a flow of said water out of said chamber; said filter further comprising and o characterised by a plurality of inner chamber walls defining a network of channels within said chamber; wherein said plurality of channels are configured to house said granular water filter material, said water being configured to flow from said inlet through said plurality of channels, in contact with said granular water filter material and out of said filter via said at least one outlet.

According to a fifth aspect of the present invention, there is provided a liquid treatment filter comprising: a main body defining a chamber capable of housing a granulate liquid treatment material; an inlet capable of allowing a flow of a liquid into said filter; an outlet capable of allowing a flow of said liquid out of said filter; said filter further comprising and characterised by flow deflection means housed within said chamber, said flow deflection means being configured to deflect a flow of said liquid flowing between said inlet and said outlet within said chamber; wherein said filter is configured to provide a plurality of flow paths of said liquid flowing between said inlet to said outlet.

The liquid treatment filter is configured to control the flow rate of liquid through the device, in part, by the cross-sectional area of the inlet whereby a total cross-sectional area of the inlet is less than a total cross-sectional area of the outlet. Further, the filter may comprise a sealing lid configured to mate with the main body of the filter so as to provide a seal for the granular filter material within the chamber. A projection may be incorporated at the sealing lid, the inlet being provided at substantially one end of the projection within the chamber.

Preferably, the projection comprises a cylindrical-like configuration, whereby the outlet is provided at a cone-like end portion of the projection.

According to a sixth aspect of the present invention there is provided an insert for a liquid treatment filter, said filter comprising a chamber capable of housing a liquid treatment medium, an inlet configured to allow a flow of a liquid into said chamber and an outlet configured to allow a flow of said liquid out of said chamber, said insert being characterised in that a flow direction of said liquid through said filter is diverted by said insert, said insert being positioned between said inlet and said outlet; wherein said flow of said liquid within said chamber between said inlet and said outlet involves a flow of said liquid in a first direction and a flow of said liquid in a second direction, the liquid flow between said inlet and said outlet being in contact with said liquid treatment medium.

According to a further specific aspect of the present invention, there is provided a liquid filter jug, a liquid heating appliance and a liquid cooling appliance, each comprising a filter as described herein.

Brief Description of the Drawings

For a better understanding of the invention and to show how the same may be carried into effect, there will now be described by way of example only, specific embodiments, methods and processes according to the present invention with reference to the accompanying drawings in which:

Fig 1 herein illustrates a cross-sectional side elevation view of a liquid filter jug comprising a filter according to a specific implementation of the present invention;

Fig 2 herein illustrates a cross-sectional side elevation view of a filter comprising a first inner sub-chamber and an annular sub-chamber according to a specific implementation of the present invention;

Fig 3 herein illustrates a cross-sectional side elevation view of the filter of figure 2 herein further comprising the granular filter material according to a specific implementation at the present invention;

Fig 4 herein illustrates a perspective view of a filter cartridge insert configured to deflect the flow of liquid flowing through the filter cartridge according to a specific implementation of the present invention;

Fig 5 herein illustrates a side elevation view of the insert of figure 4 herein; Fig 6 herein illustrates a perspective view of a sealing lid comprising a projection and cartridge inlet formed at one end of the projection according to a specific implementation at the present invention;

Fig 7 herein illustrates a plan view of the inlet of figure 6 herein;

Fig 8 herein illustrates a cross-sectional side elevation view of a lower portion of the filter cartridge comprising two outlets arranged in an apex-like configuration at a base region of the filter according to a specific implementation at the present invention;

Fig 9 illustrates one outlet of the filter cartridge comprising a plurality of ribs arranged as a triangular prism or pyramid in addition to a support rib extending over a portion of the outlet according to a specific implementation at the present invention;

Fig 10 herein illustrates a plan view of a lower portion of the filter cartridge comprising four outlets positioned at a base section of the cartridge according to a specific implementation at the present invention;

Fig 11 herein illustrates a plurality of ribs defining a plurality of outlet orifices arranged as slots or slits, the ribs being arranged as a triangular prism according to a specific implementation of the present invention;

Fig 12 herein is a graph of flow rate of liquid through the filter cartridge;

Fig 13 herein is a graph of liquid flow rate for a liquid flowing through the filter cartridge;

Fig 14 herein is a cross-sectional side elevation view of a filter cartridge comprising a plurality of internal channel walls defining a plurality of internal channels through which liquid is configured to flow according to a further specific implementation of the present invention.

Detailed Description There will now be described by way of example a specific mode contemplated by the inventors. In the following description numerous specific details are set forth in order to provide a thorough understanding. It will be apparent however, to one skilled in the art, that the present invention may be practiced without limitation to these specific details. In other instances, well known methods and structures have not been described in detail so as not to unnecessarily obscure the description.

A liquid treatment device is provided and in particular an insert for a liquid treatment filter device configured to deflect flow of a liquid flowing between the inlet and outlet of the filter so as to extend the liquid flow path through the filter.

Extended contact is therefore provided between the liquid treatment material and the liquid so as to provide greater treatment of the liquid by the filter.

Additionally, a liquid treatment filter is provided with an outlet comprising a plurality of orifices in the form of slits or slots configured to be in direct contact with the liquid treatment medium. The orifices, slits or slots comprise a width or diameter being equal to or less than the width or diameter of the granular liquid treatment material whereby loss of the treatment material from the filter cartridge is prevented by the dimensions and configuration of the outlet. Requirement for a mesh to prevent loss of the filter material is thereby avoided.

According to the relative dimensions and configuration of the inlet and outlet together with consideration of the internal liquid flow channels or chambers, the filter cartridge is configured to control the flow rate of liquid through the cartridge over extended periods of use without an observed blocking of the outlet by the filter material. A compact filter cartridge is thereby provided being of reduced overall volume with regard to prior art filter devices whilst providing extended contact between the liquid and liquid treatment material.

Referring to figure 1 herein there is illustrated a cross-sectional elevation view of a liquid treatment jug 100 comprising pre-treated liquid storage chamber 101 ; post-liquid treatment chamber 102; filter jug body 103; chamber dividing walls 104; handle 105; spout 106; lid 107; and filter cartridge 108.

Jug body 103 defines an inner chamber being divided by chamber walls 104 and cartridge 108 into two chambers 101 , 102. The chamber walls 104 and cartridge 108 are positioned substantially midway between jug base 111 and lid

107. Chamber wall 110 being connected to wall 104, in part, defines spout 106 together with main body 103. Lid 107 is moveable between an open and closed positioned allowing the transfer of a liquid into chamber 101. Handle 105 is positioned on an exterior of main body 103 so as to allow a user to grasp the filter jug and decant water therefrom.

Positioned between filter cartridge 108 and inner walls 104 is provided filter securing means 109 configured to releaseably secure the filter cartridge 108 to the jug 100. Securing means 109 may comprise any form of releasable attachment including a snap-fit attachment, bayonet type fitting and the like.

In use, untreated liquid, particularly water, is poured into pre-storage chamber 101 by displacing lid 107. The untreated liquid flows through filter cartridge 108 and into the lower chamber 102 positioned directly underneath chamber 101. The flow of liquid through the filter cartridge from chamber 101 into chamber 102 being under the force of gravity. Housed within filter cartridge 108 is a filter treatment medium (not shown) which functions to remove minerals and/or selected ions, in particular chloride, from the untreated liquid. Following the transfer of liquid from the chamber 101 to chamber 102, the treated, filtered liquid maybe decanted from the jug 100 via spout 106 being connected directly to chamber 102.

5 According to the present invention the filter material within the cartridge 108 is in direct contact with a filter cartridge outlet (not shown) positioned at a base region of the cartridge.

Referring to figures 2 and 3 herein there is illustrated a cross-sectional o elevation view of the liquid treatment filter as detailed with reference to figure 1 herein comprising at least one outlet 200; at least one support rib 201 ; a plurality of elongate members 202; an outer chamber wall 203; an inner chamber wall 204; at least one inlet 205; an inlet support member 206; orifices 207; filter lid 209 and chambers 210, 211. 5

At least one outlet 200 is provided at a base region of the filter 108. The at least one outlet is defined by a plurality of elongate members, or ribs 202 being arranged in a step-like triangular prism configuration tapering inwardly towards the chamber 210, 211. The elongate members or ribs 202 maybe formed o integrally or non-integrally with the exterior wall 203 so as to define a plurality of orifices or slits formed between the elongate members or ribs being configured to allow the flow of fluid from within chamber 210 out of the filter cartridge.

According to the specific implementation of the present invention the filter 5 comprises an inner wall 204 configured to divert or deflect the flow of liquid between the inlet 205 and outlet 200. The inner chamber wall 204 defines the first chamber 211 and second chamber 210, both chambers being configured to house the granular filter material. Inlet 205 comprises a plurality of orifices or slits configured to allow the flow of liquid from the liquid storage chamber 101 through o column 208 and into filter chamber 211. According to the present invention the plurality of orifices formed at the inlet are formed as a plurality of slits on a conical end portion of cylindrical member 206 projecting into an interior of filter chamber 211. A plurality of orifices 207 interconnect chambers 211 and 210 allowing the free flow of liquid between the chambers from inlet 205 to outlets 200. Filter lid 209 provides a seal for filter chambers 210, 211 preventing the escape of the liquid treatment material. Accordingly, water stored within chamber 101 is prevented from entering the filter other than by the inlet 205. Similarly, liquid flowing out of chamber 211 is prevented from escaping from the cartridge other than passing into chamber 210.

A mesh or similar webbing 212 maybe provided at an interior side of outlet 200 relative to inner chamber 210. According to the specific implementation of the present invention involving a plurality of outlets, the mesh 212, positioned at a base region of the filter cartridge is configured to span and cover all of outlets

200.

The support ribs 201 are provided, substantially transverse to the elongate members 202 so as to provide a structural support.

In use, the liquid flows from a source of untreated liquid, such as an untreated liquid storage chamber 101 past the filter lid 209 as indicated by arrows 301 , 302. Both filter chambers 211 and 210 house the liquid treatment filter material being a granular iron exchange/chloride removal resin. The liquid, on passing through inlet 205 is forced to flow against gravity, arrow 303, in an upward direction through the inner chamber, in contact with the ion exchange resin. The liquid flows through the plurality of orifices 207, arrow 304, and into the second, annular chamber 210, also housing the ion exchange resin. The liquid then flows under gravity down the second chamber, in contact with the filter material and out of the cartridge outlets 200, arrow 305.

Referring to figures 4 and 5 herein there is illustrated a perspective and side elevation view of the liquid treatment filter insert 204 as detailed in figures 1 to 3 herein. The insert comprises a walled section 400 defining a cone-like shape with tapering side walls as detailed in figure 5 herein extending between a plurality of orifices 402 positioned at one end of the walled section 400 and locating means 401 positioned at an opposite end of the walled section 400. Locating means 401 comprises means suitable for co-operating with the main body of the filter cartridge so as to correctly seat the insert within the cartridge. 5 For example, locating means 401 is formed as a ridge configured to fit within a groove forming part of the interior of the main body of the cartridge.

The thickness and corresponding strength of the internal chamber wall 400 of the insert is such so as to provide a means for separating the granular filter o material into first and second sub-chambers 210, 211. Additionally, the thickness and strength of the insert wall 400 is sufficient so as to deflect the flow of liquid between the inlet 205 and at least one outlet 200.

The plurality of orifices 402 are defined by a plurality of elongate ribs or 5 strips 403 extending away from the internal chamber wall 400 of insert 204. The width of the orifices 402 is sufficient to allow the free flow of liquid between the inner sub-chamber 211 to the annular sub-chamber 210. According to further specific embodiments, the size and in particular the width and length or diameter of the orifices 402 maybe selectively adjusted so as to control the flow rate of 0 liquid through the cartridge. The size of the orifices 402 is also configured to prevent passage of the granular ion exchange resin between sub-chambers 210, 211.

The plurality of orifices 402 are boarded at their outer most regions by 5 boarder 404, the thickness of which varies around the perimeter of the upper portion of insert 204. According to the specific implementation of figures 4 and 5 herein boarder 404 is devoid of orifices. However, according to a further specific implementation boarder region 404 may comprise a plurality of orifices or slots distributed around the edge of the insert. The width of the slots may be the o same, smaller or greater than the width of orifices 402. In operation, the slots positioned within boarder 404 are configured to encourage air to pass from the outer, annular sub-chamber 210 through the inner chamber 211 and out of air escape slots provided within the filter lid 209. The provision of the slots within boarder 404 and the air escape slots within filter lid 209 serves to prevent air bubbles forming within the inner chambers which would otherwise inhibit the flow of liquid through the filter cartridge. Accordingly, means are provided to allow air to escape from the inner channels and/or inner chambers, the air being expelled through suitable air escape slots provided within the filter cartridge.

As detailed with reference to figures 2 to 4 herein, the main body of the cartridge 203 and the sub-chamber dividing wall 200 are formed non-integrally whereby the insert 204 maybe releasable attached to an interior of the cartridge.

According to further specific implementations, the internal chamber wall 400 maybe formed integrally with the main body of the cartridge 203.

Figure 6 herein is a perspective view of the inlet and sealing cap of the filter cartridge 108. The sealing cap 209 comprises a wall section 602; drainage means 600; sealing lip 601 ; cylindrical projection 208; conical end portion 604; plurality of orifices 603 and upper surface 605.

Sealing lip 601 defines a perimeter of the sealing cap configured to mate with the main body 203 of the cartridge 108 so as to provide a tight seal preventing loss of liquid and the granular resin from the within the cartridge when in use. Drainage means 600 are located in close proximity to the projection 208 defining channel-like guide means serving to guide liquid from a region above the cartridge down into projection 208 and through the inlet formed by the plurality of orifices 603 at an end portion of projection 208. Upper surface 605 being an upper portion of wall 602 is in contact with untreated liquid when in use, the only means by which liquid flows into and through the cartridge is via the plurality orifices 603. Sealing cap 209 is configured to snap fit onto main body 203 so as to seal the filter material within the cartridge. Additional sealing means may also be provided at the interface between the cap and main body 203, for example o- rings and the like.

5

According to the specific implementation of the present invention projection 208 is configured to project into the inner sub-chamber 211 whereby liquid flows out of orifices 603 into a lower region of chamber 211. By positioning the inlet in close proximity to the liquid deflecting means 204 a liquid treatment filter is o provided configured to provide a plurality of liquid flow path directions through the filter cartridge, thereby extending the exposure and contact time of the liquid and filter material housed within the cartridge.

Figure 7 herein illustrates a plan view of the conical end portion 604 of 5 projection 208 comprising a plurality of orifices 603 in the form of slits radially distributed about a central point of the cylindrical end portion. The dimensions of the orifices or slits 603 prevent loss of the granular filter material from within the inner chamber.

0 Referring to figures 8 and 9 herein, there is illustrated a side elevation view of a lower portion of the filter cartridge 108 as detailed with reference to figures 2 and 3 herein. Provided at a base region of filter 108 is at least one outlet being defined by a plurality of elongate members or ribs 202 arranged in a step-like configuration tapering inwardly towards inner chamber 800. According to the 5 specific implementation of the present invention inner chamber 800 is divided into a first sub-chamber 211 and second sub-chamber 210 by flow deflection means 204. The elongate members or ribs 202 may be formed integrally or non- integrally with the exterior wall 203 so as to define a plurality of orifices or slits formed between the elongate members or ribs configured to allow the flow of o liquid from within chamber 800 out of the filter cartridge. Figure 9 herein illustrates the ribs 202 arranged in a step-like configuration, the outlet orifices being positioned at at least one face of a pyramid or triangular prism tapering inwardly towards the interior of the filter cartridge. According to further specific implementations of the present invention, the pyramid of triangular prism-like configuration of the at least one outlet may project outwardly from the interior of the filter cartridge. According to the specific implementation, as the outlet is formed as a step-like structure, the orifices of the outlet are formed at the angle between the steps of the pyramid or triangular prism. One or more support ribs 201 are provided on each face of the pyramid or triangular prism, substantially transverse to and in contact with the elongate members or ribs so as to provide structural support inhibiting separation of the elongate members and a corresponding widening of the orifices. The support ribs 201 may extend the full distance across the outlet or may extend over a portion of each outlet face. According to the specific implementation of the present invention the elongate members or ribs are inclined towards the interior of the filter chamber at an angle of approximately 120°.

Figure 10 herein illustrates a plan view of the lower region of the filter cartridge from the interior of the cartridge. Four outlets 200 are provided at a lower base section 1000, 1001 of the filter cartridge 108. At least one chamber wall 203 connects the base section 1001, 1000 to a sealing lip 1002 positioned at an upper region of the filter cartridge and configured to receive sealing lip 601 of cap 209. Securing means 109 are provided at opposed regions of the cartridge 108 configured to mate with suitable anchoring means configured to anchor the filter cartridge 108 into position as detailed with reference to figure 1 when for example the cartridge is secured within a water filter jug. Central base region 1000 is configured with a groove-like recess configured to receive projection 801 of the liquid flow deflection means 204 so as to provide a dual chamber cartridge, each of the inner sub-chambers being configured to house the filter material.

Referring to figure 11 there is illustrated a perspective view of outlet 200 being defined by a plurality of elongate members or ribs 202 arranged in a cascading stepped configuration formed as a triangular prism. Each elongate member 202 comprises a substantially vertical face 1102 and a substantially horizontal face 1101. A plurality of slits 1100 are defined by neighboring elongate members and inparticular slits 1100 are bordered along their length by a substantially horizontal face 1101 of a first elongate member and a substantially vertical face 1102 of a neighboring elongate member. The elongate members are held in place, in the step-like arrangement, at least one support rib 201 (not shown) and suitable structural support means (not shown) positioned at the end regions of the prism-like structure.

Each elongate member is displaced substantially above a lower, neighboring elongate member whereby an upper edge 1103 of a lower positioned rib is substantially aligned with a lower edge 1104 of a neighboring upper rib. The width of these slits or distance between adjacent faces 1101 and 1102 of neighboring slits is in the approximate range 0.125 mm to 0.175 mm, the width being less than a diameter or thickness of the granular filter material.

In use, the granular filter material is housed within each of the inner sub- chambers or channels in direct contact with the outlet slits 1100. Due to the relatively positioning of the substantially transverse faces 1102, 1101 defining the slits, the granular filter material is prevented from packing densely against the slits thereby avoiding blocking of the outlets. Due to the positioning of the slits on sloping faces of the prism-like structures, the granules are stacked, one on top of one another on faces 1101 against faces 1102. Accordingly, a network of granules is built up directly upon the ribs 202 such that the force exerted by the moist granular material onto the outlet is distributed across the plurality of faces 1101 and 1102, the granules being allowed to cascade down the faces of the prism.

Referring to figure 12 herein there is illustrated a liquid flow rate graph illustrating the amount of time taken for consecutive single litres of liquid to flow through the filter cartridge. Data point 1200 corresponds to the time taken for a first liter of liquid to flow through the filter cartridge, this taking 1 minute 44 seconds. The time taken to process the 25th litre of liquid through the filter cartridge_;, data point 1201 is 1 minute 42 seconds and the time taken for the 45th litre of liquid to flow through the filter cartridge, data point 1202 is 1 minute 44 seconds.

The results presented in figure 12 illustrate the substantially constant flow rate of liquid through the filter cartridge being largely independent of the number of litres having been processed. The results confirm the free flow of liquid through the device without observed blocking of the outlet which otherwise would result in an observed increase in the flow rate of liquid through the device and a corresponding positive gradient of the results presented in figure 12. With investigations concerning prior art filter cartridges, the inventors have observed it taking as long as 600 seconds to process a first litre of liquid due to the clogging of the mesh outlet of the filter cartridge.

Figure 13 herein illustrates liquid flow rates through the filter cartridge comprising four outlets as detailed with reference to figs 2 to 11 herein. Data point 1300 corresponds to the time taken for the 15th litres of liquid to flow through the filter device, this being 2 minutes 16 seconds with the 45th litre (data point 1301 ) taking two minutes to process and the 85th litre (data point 1302) taking 2 minutes 5 seconds to process. Figure 13 further confirms the absence of outlet clogging by the moist granular filter material due to the observed substantially uniform liquid flow rates.

Referring to figure 14 herein, there is illustrated a liquid filter cartridge 1400 according to a further specific implementation of the present invention comprising at least one outlet 1401 ; at least one inlet 1402; a main body 1403 defining an inner chamber of the filter cartridge; a sealing lid 1404; at least one channel wall 1405 defining a plurality of channels 1407. The main body 1403 defines an internal chamber which is segregated into channels 1407 by the plurality of channel walls 1405 configured to divert the flow of liquid flowing from the inlet 1402 to the at least one outlet 1401. The main body 1403 and sealing lid 1404 are configured to mate together so as to securely house a granular filter material within each of the channels 1407. The channel walls 1405 may comprise any form of member or plate positioned substantially across a cross section of the filter cartridge however at least one gap or orifice is provided 1406 in this cross section to allow the flow of liquid from one channel to the next. The filter material is housed within each of the channels 1407 in direct contact with the outlet 1401. Each neighboring channel wall projects from the main body 1403 at alternating opposed regions of the cartridge so as to form a plurality of staggered ribs or plates whereby neighboring gaps or orifices 1406 positioned in the plane of the channel walls 1405 are provided at opposed regions of the cartridge body along its length.

In operation, liquid flows from the inlet 1402 and into a first channel 1407 in a first flow direction and into a second channel 1407 in an opposite flow path direction to that of the proceeding channel. The liquid flow path direction between the inlet and outlet must therefore change, involving a plurality of flow path directions through the filter. Extended contact between the filter material and the liquid flowing through the cartridge is therefore achieved providing a more compact filter cartridge than is found in the art.

According to a further embodiment of the present invention, figure 15 herein illustrates a perspective view of a lower portion of a filter cartridge 1500 comprising a chamber wall 1501 ; two projections 1502; a base region 1503; a first face of a projection 1504 and a second face of a projection 1505.

Each projection 1502 extends from base region 1503 towards the interior of the filter cartridge. Each projection comprises a length extending a distance over base region 1503, each projection being curved along its length. First and second walls 1504, 1505 taper inwardly from base region 1503 towards the interior of the chamber defined by chamber walls 1501. Accordingly, each face 1504, 1505 is a sloping face being aligned transverse to the base 1503 and walls 1501. Each projection 1502 is formed as a truncated prism having a length corresponding to an arc of a circle.

Figure 16 herein illustrates a perspective view of one projection 1502 as detailed with reference figure 15 herein. Each projection comprises a plurality of ridges 1600 extending across each face 1504 and 1505. The projections extend outwardly away from face 1504 extending between a region of the projection being inner most within the chamber and the base region 1503. As illustrated with reference to figure 16 herein the ridges extend between an upper region of the projection and a lower region of the projection in a plane substantially transverse to a plane of base region 1503. A region of each face 1504 separates each projection. Each projection, in the form of a square based truncated prism, curved along its length, comprises a substantially flat upper surface 1604. Upper surface 1604 is substantially parallel to base section 1503.

A plurality of slits 1601 are provided in close proximity to each projection 1600, each slit being formed on face 1504. In particular, each slit 1601 is positioned at the angle between ridges 1600 and face 1504 and extend a distance of the height of projection 1502, that is from base region 1503 towards the interior of the chamber defined by chamber walls 1501. Slits 1601 may be provided at one side of each ridge or may be provided on both sides at the junction with the face 1504. Alternatively, the slits may be formed at any position along the length of each ridge or in close proximity thereto. As detailed with reference to figure 5 herein the width of slits 1601 is configured to inhibit loss of the granular filter material from the filter cartridge chamber, whilst allowing a flow of liquid out of the chamber.

Figure 17 herein is a cross-section, elevation view of the cartridge outlet as detailed with reference to figure 15 herein. The projection 1502 extends from base region 1503 inwardly towards the cartridge chamber defined by walls 1501. A width of the projection decreases from base region 1503 to the chamber interior whereby faces 1504, 1505 taper inwardly towards the chamber interior from base 1503. The granular filter material therefore is configured to cascade down the tapering faces of the projection which serves to inhibit blockage of the slits 1601 by the filter material.

Figure 18 illustrates a plan view of the interior of the filter cartridge as detailed with reference to figure 15 herein. Two projections are provided at base region 1503 positioned opposed to one another. Each projection being substantially curved along its length is configured to correspond to the curvature of the perimeter of base section 1503. Accordingly each face of the projection is also curved along its length.

As illustrated with reference to figure 18 herein each ridge extending from faces 1504, 1505 comprises a substantially rectangular or square cross-section. Each face and ridge being terminated at base 1503 and upper surface 1604 of each projection.

According to further specific implementations, projections 1502 may be formed with non-tapering faces 1504, 1505, whereby each face is aligned substantially perpendicular to base section 1503. According to yet further specific implementations, projections 1502 may extend from the chamber walls 1501 where the internal chamber is defined by the chamber walls without inclusion of base section 1503.

Claims

Claims:

1. A liquid treatment filter (180, 1400) comprising:

at least one chamber (210, 211 , 1407) being defined by an outer chamber wall (203, 1403, 1501), said chamber capable of housing a liquid treatment medium;

at least one inlet (205, 1402) configured to allow a flow of a liquid into said at least one chamber;

at least one outlet (200, 1401 , 1502) configured to allow a flow of said liquid out of said at least one chamber;

said filter further comprising and characterised by:

at least one inner channel wall (204, 1405) positioned within said at least one chamber, said at least one channel wall being configured to guide the flow of said liquid from said inlet to said outlet in a plurality of different flow directions;

wherein a liquid flow path within said filter is extended by said at least one channel wall.

2. The filter as claimed in claim 1 wherein said at least one inner channel wall comprises a plurality of walls (1405) positioned within said at least one chamber to form a network of channels (1407) through which said liquid flows.

3. The filter as claimed in claims 1 or 2 wherein said at least one chamber is divided into a plurality of inter-linked chambers (210, 211 , 1407) through which said liquid can flow.

4. The filter as claimed in claim 1 wherein said at least one chamber is divided into a first chamber and a second chamber by a single inner channel wall, said inner channel wall comprising at least one orifice (207, 1406) configured to allow a flow of said liquid from said first chamber into said second chamber between said inlet and said outlet.

5. The filter as claimed in claim 4 wherein said at least one orifice comprises a plurality of slits (1100).

6. The filter as claimed in anyone of claims 1 to 5 wherein said outer chamber wall is formed integrally with said at least one inner channel wall.

7. The filter as claimed in anyone of claims 1 to 5 wherein said outer chamber wall is formed non-integrally with said at least one inner channel wall.

8. The filter as claimed in anyone of claims 1 to 7 wherein said inlet is formed within a filter cap (209, 1404) configured for releasably affixing to a portion of said outer chamber wall.

9. The filter as claimed in claim 8 wherein said cap comprises a projection (208), said projection extending into said chamber, said inlet being positioned substantially at one end of said projection.

10. The filter as claimed in any one of claims 1 to 9 wherein said inlet comprises a plurality of orifices (603) configured to control the flow of said liquid into said filter.

11. A liquid treatment filter (108, 1400) comprising:

a main body (203, 1403, 1501 ) defining a chamber (210, 211 , 1407) capable of housing a liquid treatment medium; at least one inlet (205, 1402) configured to allow a flow of a liquid into said chamber;

at least one outlet (200, 1401 , 1502) configured to allow a flow of said liquid 5 out of said chamber;

said filter further comprising and characterised by:

at least one internal chamber wall (204, 1405) dividing said chamber into a o plurality of sub-chambers;

wherein said filter is configured to allow a flow of said liquid from said inlet to said outlet through said plurality of sub-chambers involving at least one direction change of the flow of said liquid through said filter. 5

12. The filter as claimed in claim 11 wherein said at least one internal chamber wall comprises a plurality of orifices (207, 1406) configured to allow a flow of said liquid between said sub-chambers.

0 13. The filter as claimed in claims 11 or 12 wherein said inlet is provided at a first sub-chamber of said plurality of sub-chambers and said outlet is provided at a further sub-chamber of said plurality of sub-chambers.

14. The filter as claimed in anyone of claims 11 to 13 wherein said inlet 5 and said outlet are configured to be in direct contact with said liquid treatment medium, said plurality of sub-chambers being capable of housing said liquid treatment medium.

15. The filter as claimed in anyone of claims 11 to 14 wherein said inlet 0 comprises a plurality of orifices (603) and said outlet comprises a plurality of orifices (1100, 1601).

16. The filter as claimed in claim 15 wherein said outlet comprises at least one projection extending from a base region of said chamber, said plurality of orifices being provided on said at least one projection.

17. The filer as claimed in anyone of claims 11 to 16 wherein said chamber is divided into an inner sub-chamber (211) and an annular sub-chamber (210) said annular sub-chamber surrounding a portion of said inner sub-chamber.

18. The filter as claimed in claim 17 wherein said inlet is provided at said inner sub-chamber and said outlet is provided at said annular sub-chamber.

19. The filter as claimed in anyone of claims 11 to 17 wherein in a total cross-sectional area of said inlet is less than a total cross-sectional area of said outlet, said cross-sectional area of said inlet being configured to control a flow rate of said liquid through said filter.

20. The filter as claimed in anyone of claims 11 to 18 wherein said liquid treatment medium comprises a granulate ion exchange resin.

21. The filter as claimed in anyone of claims 11 to 19 further comprising a mesh, said mesh being provided over and about said outlet.

22. A liquid treatment filter (180, 1400) comprising:

a main body (203, 1402, 1501) defining a chamber (210, 211, 1407) capable of housing a granulate filter material;

an inlet (205, 1402) configured to allow a flow of a liquid into said chamber;

an outlet (200, 1401, 1502) configured to allow a flow of said liquid out of said chamber; said filter further comprising and characterised by:

at least one inner chamber wall (204, 1405) being housed within said chamber, said inner chamber wall defining a first sub-chamber and a second 5 sub-chamber;

at least one orifice (207, 1406) formed within said inner chamber wall;

wherein said inlet is provided at said first sub-chamber and said outlet is o provided at said second sub-chamber, said filter being configurable to allow a flow of said liquid from said inlet to said outlet via said first sub-chamber and said second sub-chamber.

23. The filter as claimed in claim 22 wherein said first sub-chamber and 5 said second sub-chamber are configured to house said granulate filter material.

24. The filter as claimed in claims 22 or 23 further comprising a sealing lid (209, 1404) configured to mate with said main body and seal said chamber.

0 25. The filter as claimed in claim 24 wherein said lid comprises a projection (208) configured to project into said first sub-chamber, said inlet being provided at one end of said projection.

26. The filter as claimed in anyone of claims 22 to 25 wherein said inlet 5 comprises at least one orifice (603) and said outlet comprises a plurality of orifices (1100, 1601) being formed on at least one projection extending from a base region of said filter.

27. The filter as claimed in claim 26 wherein said inlet and said outlet o are configured to be in direct contact with said granulate filter material.

28. The filter as claimed in anyone of claims 22 to 27 wherein the flow of said liquid through said filter involves a flow in a first direction through said first sub-chamber and a flow in a second direction through said second sub-chamber, said first and second flow direction being transverse to one another.

29. The filter as claimed in anyone of claims 26 to 28 wherein a total cross-sectional area of said at least orifice of said inlet is less than a total cross- sectional area of said plurality of orifices of said outlet whereby a flow rate of said fluid through said filter is controlled by said inlet.

30. The filter as claimed in anyone of claims 22 to 29 wherein said main body and said at least one inner chamber wall are formed integrally.

31. The filter as claimed in anyone of claims 22 to 29 wherein said main body and said at least one inner chamber wall are formed non-integrally.

32. The filter as claimed in anyone of claims 22 to 31 further comprising a mesh substantially enclosing said outlet.

33. A water treatment filter cartridge (180, 1400) comprising:

a main body (203, 1403, 1501 ) defining a chamber configured to house a granular water filter material;

at least one inlet (205, 1402) capable of allowing a flow of water into said chamber;

at least one outlet (200, 1401 , 1502) capable of allowing a flow of said water out of said chamber;

said filter further comprising and characterised by: a plurality of inner chamber walls (204, 1405) defining a network of channels within said chamber;

wherein said channels are configured to house said granular water filter 5 material, said water being configured to flow from said inlet through said plurality of channels in contact with said granular water filter material and out of said filter via said at least one outlet.

34. The filter as claimed in claim 33 wherein said main body and said o inner chamber walls are formed integrally.

35. The filter as claimed in claim 33 wherein said main body and said inner chamber walls are formed non-integrally.

5 36. The filter as claimed in anyone of claims 33 to 35 wherein said outlet comprises a plurality of slits being formed on at least one projection (200, 1401 , 1502) projecting into said chamber from said main body.

37. The filter as claimed in claim 36 wherein said plurality of slits o comprise a width being less than a diameter of each granule of said granulate filter material wherein said slits are configured to inhibit loss of said granular filter material from said chamber.

38. The filter as claimed in anyone of claims 33 to 37 further comprising 5 a mesh configured for positioning at said outlet, said mesh being configured to inhibit loss of a carbon based filter material from said filter.

39. A liquid treatment filter (108, 1400) comprising:

0 a main body (203, 1403, 1501 ) defining a chamber (210, 211 , 1407) capable of housing a granulate liquid treatment material; an inlet (205, 1402) capable of allowing a flow of a liquid into said filter;

an outlet (200, 1401 , 1502) capable of allowing a flow of said liquid out of said filter;

said filter further comprising and characterised by:

flow deflection means (204, 1405) housed within said chamber, said flow deflection means being configured to deflect a flow of said liquid flowing between said inlet and said outlet within said chamber.

40. The filter as claimed in claim 39 wherein said outlet comprises a plurality of projections extending into said chamber from a base region of said filter, each projection comprising at least one face being aligned transverse to said base region, each face comprising a plurality of orifices comprising a width being less than a diameter of each granule of said granulate liquid treatment material.

41. The filter as claimed in claim 40 wherein said inlet comprises a plurality of orifices (603), wherein a total cross-sectional area of said orifices of said inlet is less than a total cross-sectional area of said orifices of said outlet, said inlet being configured to control a rate of flow of said liquid through said filter.

42. The filter as claimed in anyone of claims 39 to 41 further comprising a sealing lid (209, 1404) configured to mate with said main body and to seal said filter, said inlet being provided at said sealing lid.

43. The filter as claimed in claim 42 further comprising an inlet projection (208) configured to project into said chamber, said inlet being provided at substantially one end of said inlet projection within said chamber.

44. The filter as claimed in claim 43 wherein said inlet projection comprises a cylindrical-like configuration and said inlet is provided at a cone-like end portion of said projection.

45. An insert (204, 1405) for a liquid treatment filter (108, 1400), said filter comprising a chamber (210, 211 , 1407) capable of housing a liquid treatment medium, an inlet (205, 1402) configured to allow a flow of a liquid into said chamber and an outlet (200, 1401, 1502) configured to allow a flow of said liquid out of said chamber;

said insert being characterised in that:

a flow direction of said liquid through said filter is diverted by said insert, said insert being positioned between said inlet and said outlet;

wherein said flow of said liquid within said chamber between said inlet and said outlet involves a flow of said liquid in a first direction and a flow of said liquid in a second direction, the liquid flow between said inlet and said outlet being in contact with said liquid treatment medium.

46. A liquid filter jug (100) comprising a filter as claimed in anyone of claims 1 to 45.

47. A liquid heating appliance comprising a filter as claimed in anyone of claims 1 to 45.

48. A liquid cooling appliance comprising a filter as claimed in anyone of claims 1 to 45.