WO2018001458A1

WO2018001458A1 - Device for forming a liquid treatment apparatus and liquid treatment apparatus

Info

Publication number: WO2018001458A1
Application number: PCT/EP2016/064979
Authority: WO
Inventors: Jochen Zoeller
Original assignee: Brita Gmbh
Priority date: 2016-06-28
Filing date: 2016-06-28
Publication date: 2018-01-04

Abstract

A device for forming a liquid treatment apparatus (1) includes a main part and a receiving part (33). The receiving part (33) includes a cavity having a mouth, wherein the cavity is arranged to receive through the mouth a connecting head (10) of a replaceable liquid treatment cartridge (3,4,5) having at least one port (12-15) in liquid communication with an interior of the liquid treatment cartridge (3-5), such that the at least one port(s) (12-15) of the connecting head (10) are in sealed liquid communication with corresponding ports (37-40) of the receiving part (33). The receiving part (33) is supported for movement with respect to the main part whilst the connecting head (10) is inserted in the cavity. The device further includes a screening part (35;35'). The screening part (35;35') is provided with an aperture (82;82'). The screening part (35;35') is positioned in front of the receiving part (33). The screening part (35;35') is guided to enable movement with respect to the main part with the aperture (82;82') aligned with the mouth.

Description

DEVICE FOR FORMING A LIQUID TREATMENT APPARATUS AND LIQUID TREATMENT APPARATUS

The invention relates to a device for forming a liquid treatment apparatus.

The invention also relates to a head part for forming a liquid treatment apparatus. The invention also relates to a device including a head part for forming a liquid treatment apparatus.

The invention also relates to a kit of parts for assembling a device for forming a liquid treatment apparatus.

The invention also relates to a method of assembling a device for forming a liquid treatment apparatus.

The invention also relates to a liquid treatment apparatus including a replaceable liquid treatment cartridge and a head part.

International patent application No. PCT/EP2016/057741 was filed before and published after the date of filing of the present applica- tion. It discloses a liquid treatment apparatus including a head part and a replaceable liquid treatment cartridge. The head part includes a housing including left and right housing parts joined together. The liquid treatment cartridge has a housing comprising a vessel of which the opening is closed by a cap-shaped part including a connecting head. A receiving part is movably journalled within the housing of the main part for movement between a first position, in which the connecting head is insertable into and retractable from a cavity defined in the receiving part, and a second position, in which the cartridge is locked to the head part. Movement of the receiving part is coupled to that of the connecting head between the first and second positions. The receiving part is able to carry out a combined displacement and intrinsic rotation between the first and second position within the housing formed by the left and right housing parts and thereby also function as a movable valve member. A cavity in the housing formed by the left and right housing parts obviously has a mouth large enough to accommodate the movement of the inserted section of the cartridge. As the receiving part moves across this mouth between the first and second positions, first and second screening parts close sections of the housing cavity mouth adjacent the receiving part so that foreign objects and dirt cannot enter easily. The screening parts are hingedly attached to the receiving part at one end and journalled to the housing at an opposite end.

The screening parts increase the number of parts, and the manner in which they are guided for movement complicate assembly of the head part.

It is an object of the invention to provide a relatively simple device and liquid treatment apparatus, wherein the device has a receiving part that can move with the inserted connecting head of a liquid treatment cartridge within the confines of a main part, but foreign objects and dirt cannot easily enter the space within which the receiving part is arranged to move.

This object is achieved according to a first aspect by the device according to the invention, which includes: a main part;

a receiving part including a cavity having a mouth, wherein the cavity is arranged to receive through the mouth a connecting head of a replaceable liquid treatment cartridge having at least one port in liquid communication with an interior of the liquid treatment cartridge, such that the at least one port(s) of the connecting head are in sealed liquid communication with corresponding ports of the receiving part,

wherein the receiving part is supported for movement with re- spect to the main part whilst the connecting head is inserted in the cavity; and

a screening part,

wherein the screening part is provided with an aperture, wherein the screening part is positioned in front of the receiv- ing part, and

wherein the screening part is guided to enable movement with respect to the main part with the aperture aligned with the mouth.

The movement of the receiving part may be a purely pivotal movement. It may be a rotary or translatory movement or a combination of a translation with respect to the main part and an internal rotation.

The screening part extends laterally with respect to a direction of insertion through the aperture. It may be essentially impermeable to liquid. Regardless of whether this is the case, it forms a screen on one side of a space in which the receiving part is arranged to move. The space is only open to this side through the aperture. The screening part is situated in front of the receiving part, so that it is adjacent the mouth of the receiving part. The connecting head of the liquid treatment cartridge can be inserted into the cavity of the receiving part by first passing through the aperture and then the mouth of that cavity. It is then surrounded laterally by the screening part, so that foreign objects cannot enter the space in which the receiving part is arranged to move. The main part of the device may be fixed in position more or less permanently. It may in particular include connectors for connecting conduits for supplying liquid to be treated and for carrying away treated liquid. These conduits may be part of the water supply in a building, for example. The receiving part is supported for move- ment with respect to the main part. Because it is movable with the connecting head inserted in the cavity, the connecting head can be inserted with the cartridge at a different orientation from the one it has in a final, operative position. In this operative position, the cartridge will generally be below the device, possibly parallel to and in close proximity to a wall on which the device is mounted. The movement of the receiving part with the connecting head inserted into the cavity allows the cartridge to be inserted from a direction that leaves more space for a user to handle the cartridge.

The sealed liquid communication between the at least one port of the connecting head of the cartridge and the corresponding ports of the receiving part can be established before the movement of the receiving part with the inserted connecting head is effected. This allows the movement of the receiving part to be combined with other operations such as locking the cartridge to the device or operat- ing a valve. Such operations might require a relatively large force, which consequently need not be exerted during insertion of the connecting head into the cavity of the receiving part. Because the screening part is provided with an aperture and positioned in front of the receiving part, it extends to screen off space adjacent the receiving part. The aperture can be aligned with the mouth of the cavity to allow the connecting head of the cartridge to be inserted into the cavity and retracted from it through the aperture. Once inserted through the aperture, the cartridge can couple the movement of the receiving part to that of the screening part. The screening part may therefore be guided for movement independent of that of the receiving part, at least in the absence of the cartridge. However, it is equally possible for the receiving part to be linked to the screening part. The shape of the aperture will generally correspond to that of the connecting head, so that foreign objects of at least a certain size will generally be prevented from passing between the cartridge and the edge of the aperture into the space in which the receiving part is arranged to move.

It is noted that the receiving part may be provided with several cavities, each for receiving a respective connecting head at an end of the cartridge. In that case, the screening part may have multiple apertures or a single aperture through which all of the connecting heads are insertable. Alternatively, there may be multiple screening parts of the type defined above.

In an embodiment of the device, the main part includes a housing defining a housing cavity in which the receiving part is arranged to move, and the screening part extends across a mouth of the hous- ing cavity.

The housing thus defines a housing cavity that may kept essentially closed by the housing and the screening part. The risk that movement of the receiving part is impeded is minimised. An embodiment of the device is arranged to allow movement of the connecting head into and out of the cavity in a first of first and second positions of the receiving part and to prevent such movement in the second position.

Movement of the receiving part with the inserted connecting head thus locks the cartridge to the device or frees it for replacement. Separate steps for locking the cartridge to the device are not absolutely necessary, although they may be required as an extra safeguard. The mere act of moving the cartridge already locks it to the device. The user can then at least let go of it, even if only to manipulate a further locking device.

In a variant of this embodiment, the main part includes at least one section defining a support surface for supporting a protruding part of the liquid treatment cartridge during movement of the receiving part between the first and second positions with the connecting head inserted.

The sections defining the support surfaces thus prevent the cartridge from being retracted, effectively locking it to the device. Because this section or these sections are included in the main part, the receiving part need not carry the weight of the cartridge and any liquid contained in it. This facilitates movement of the receiving part, as well as allowing for a relatively compact construction of the receiving part and the parts with which it is journalled for movement to the main part. In a variant hereof, the support surface includes a detent for arresting movement of the protruding part along the support surface. Because the connecting head is inserted in the cavity of the receiving part and arranged to move with it between the first and second positions, the receiving part is also held in the second position when the detents engage the protruding parts. A separate latching or locking device for directly engaging the receiving part may thus be dispensed with or be of a less robust construction. The main part can then be relatively compact, since it need not afford space for such a latching part in addition to the receiving part. Furthermore, the connecting head and receiving part are relatively easily freed from the second position merely by lifting the cartridge. A separate mechanism extending into the main part to operate a latching device acting on the receiving part can be dispensed with.

In a variant of the embodiment of the device arranged to allow movement of the connecting head into and out of the cavity in a first of first and second positions of the receiving part and to prevent such movement in the second position, wherein the main part includes at least one section defining a support surface for supporting a protruding part of the liquid treatment cartridge during movement of the receiving part between the first and second positions with the connecting head inserted, the support surface is provided by a ledge.

The ledge or ledges allow the cartridge to be supported laterally. They can be provided on the sides of a housing cavity in which the connecting head is arranged to move. The movement may be such that the protruding parts of the cartridge move along the ledge.

In a variant of this embodiment, an end of the ledge borders a channel for receiving the protruding part of the liquid treatment cartridge in the first position of the receiving part. The protruding part can move past the end of the ledge through the channel in the first position to allow the connecting head of the cartridge to be inserted into the cavity of the receiving part. Once the protruding part has passed above the level of the support surface, it is free to move along the ledge. The ledge thus ensures that the cartridge is inserted sufficiently in the first position and is locked to the device once the receiving part has moved out of the first position. The channel may also play a role in aligning an axis of the cartridge with an axis of the cavity corresponding to the intended direction of insertion.

In a variant of the embodiment of the device in which the device is arranged to allow movement of the connecting head into and out of the cavity in a first of first and second positions of the receiving part and to prevent such movement in the second position, wherein the main part includes at least one section defining a support surface for supporting a protruding part of the liquid treatment cartridge during movement of the receiving part between the first and second positions with the connecting head inserted, the receiving part has an axis corresponding to a direction of insertion of the connecting head into the cavity, and an axial distance of the support surface to an axial end of the cavity distal to the mouth decreases towards the second position over at least a section of the support surface.

Thus, the cartridge is pushed further into the receiving part as the receiving part moves from the first to the second position. At this stage, the cartridge is already supported by the main part, so that the user need not carry the full weight of the cartridge. Moreover, the connecting head is already essentially aligned with the cavity. Counteracting forces (e.g. elastic forces due to compression of seal- ing elements or friction forces due to contact between the connecting head and the receiving part) can be overcome without the user needing to exert a very large force.

In a variant of the embodiment of the device in which the device is arranged to allow movement of the connecting head into and out of the cavity in a first of first and second positions of the receiving part and to prevent such movement in the second position, the screening part includes a surface section provided with at least one indicium, occluded in only one of the first and second positions, e.g. by the main part. In the second positon, the surface section is visible through a window in an exterior surface of the main part or it protrudes from the main part.

A user is thus provided with an indication of whether the receiving part is in the first position, in which a cartridge can be inserted or retracted. The screening part is provided with an extra function.

In another variant of the embodiment of the device in which the device is arranged to allow movement of the connecting head into and out of the cavity in a first of first and second positions of the receiving part and to prevent such movement in the second position, the screening part and the receiving part are arranged to engage each other in at least one of the first and second positions, such that one arrests movement of the other in at least one direction, e.g. in a direction corresponding to movement towards the other of the first and second positions, and the device includes at least one latching device on one of the main part and the arresting one of the screening part and the receiving part, the latching device arranged releasably to restrain movement of the arresting one of the screen- ing part and the receiving part in one of the first and second positions.

It is thus possible to ensure that either or both of the operative position of the cartridge and receiving part and the position in which the cartridge can be replaced are maintained. It is, however, not necessary to provide a separate latching or locking device for both the screening part and the receiving part. The screening part and the receiving part may engage each other permanently, i.e. be coupled to each other, or only in the position in which the one arrests movement of the other. In particular in the first position, in which the cartridge may be removed, the receiving part and the screening part can remain aligned.

In a variant of this embodiment, at least one of the latching devices is an integral part of the screening part. The number of parts of the screening part may be kept relatively low. It may be a single formed, e.g. moulded, part. Because the screening part is positioned in front of the receiving part, less space need be provided for the latching device inside the main part where the receiving part is arranged to move. An embodiment of the device is included in a head part including at least one further device according to the invention, wherein the screening parts of the device and the further device include corresponding surface sections differing in appearance.

The screening part thus signals to the user the kind of cartridge to be used with each of the head part devices. The head part can thus be used to effect several different kinds of treatment. A keying sys- tern may be used to prevent a cartridge of the wrong kind being mounted in a particular one of the head part devices. The screening parts help avoid that a user attempts to mount a cartridge that does not fit. Because the screening parts close off a space in the main part in which the receiving part is arranged to move, they are at least close to the exterior of the head part devices, making them suited to fulfilling this signalling function. The differing appearance may be due to texture, colour, patterns, symbols and the like. It may be the entire surfaces of the screening parts that differ in ap- pearance.

In an embodiment of the device, the screening part includes a surface section provided with at least one indicium in the form of a colour contrasting with a colour of a majority of a remainder of the screening part. This embodiment is suitable for use in many different countries, because colours are universally recognisable. This simplifies manufacturing. The cartridges can be similarly colour-coded.

In an embodiment, the main part includes at least one of at least one inlet and at least one outlet, at least one of which is placeable in liquid communication with at least one respective one of the ports of the receiving part in at least one position of the receiving part with respect to the main part.

Thus, the receiving part need not be provided with a flexible connector to an adjacent device or conduit. This also allows it to be situated in a housing of the main device, since it need not be accessible for connection to conduits delivering liquid to be treated or carrying treated liquid to a connected appliance. Instead, a rigid connection between such a conduit and the inlet or outlet of the main part can be provided.

In a variant of this embodiment, the receiving part is movable between a first and a second position with respect to the main part, and the device further includes a valve mechanism for interrupting the liquid communication in only the first of the first and second positions.

This helps avoid leaks when the connecting head is not fully inserted or absent. Replacement of the cartridge becomes easier for the user, since there is no need to close a valve manually before replacement of the cartridge.

In a variant hereof, the receiving part is arranged to function as a movable valve member of the valve mechanism, and at least one, e.g. all of the ports of the receiving part are aligned in the second position with respective ports of the main part in only the second of the first and second positions.

This is a relatively simple valve mechanism, similar to a sliding gate valve or spool valve. Movement of the cartridge with the receiving part to the first position automatically also closes the valve. Because the receiving part functions as the movable valve member, a separate valve member with a valve body and a means of linking the valve member to the receiving part can be dispensed with. The cartridge effectively functions as the handle for the valve.

In a variant of the embodiment of the device in which the main part includes at least one of at least one inlet and at least one outlet, at least one of which is placeable in liquid communication with at least one respective one of the ports of the receiving part in at least one position of the receiving part with respect to the main part, wherein the receiving part is movable between a first and a second position with respect to the main part, and wherein the device further in- eludes a valve mechanism for interrupting the liquid communication in only the first of the first and second positions, at least one chan^¬ nel is formed in the receiving part and the main part includes at least one first port at least placeable in liquid communication with at least one of the at least one inlets, wherein the main part in- eludes at least one second port at least placeable in liquid commu^¬ nication with at least one of the at least one outlets, and wherein the channel is arranged, in at least the first position of the receiving part, to place at least one of the at least one first ports in liquid communication with at least one of the at least one second port. The channel or channels thus function as a bypass channel to ena^¬ ble liquid to pass from the inlet of the main part to the outlet of the main part even when the flow of liquid through the receiving part and the cartridge is interrupted because the receiving part is in the first position . In an embodiment of the device, the receiving part is supported for movement by protrusions arranged to move along guides.

This type of journaling allows the receiving part to carry out a rela^¬ tively complex movement relative to the main part.

In a variant of this embodiment, the protrusions are provided on the receiving part. The receiving part can be relatively compact in this variant. It need not be provided with gates or grooves. Since the main part must in any case accommodate the movement of the receiving part, it will in any case be larger than the receiving part and thus more suited to providing the guides.

In a variant of the embodiment of the device in which the receiving part is supported for movement by protrusions arranged to move along guides, the protrusions are provided on opposite sides of the receiving part, and the protrusions protrude in opposite directions generally transverse to a plane in which the receiving part is arranged to move.

The trajectory of movement of the receiving part in the plane of movement can thus have essentially any shape. The mechanism for journaling it is arranged laterally, so that the path of the cartridge can remain unobstructed.

In an embodiment of the device, the connecting head is insertable into the cavity in a direction of insertion, wherein the receiving part is supported for movement in a plane parallel to the direction of insertion, and the movement includes at least a component corre- sponding to an intrinsic rotation of the receiving part about an axis perpendicular to the plane of movement.

It is common for the cartridge to be situated below the device in the liquid treatment device. Because at least part of the connecting head is inserted into the cavity of the receiving part when the car- tridge is mounted to the device, there must be some clearance from the ground. The intrinsic rotation of the receiving part means that the cartridge is swivelled out of its operational position to replace it. It is thus not retracted purely towards the ground but also sideways. Less clearance is required, allowing, for example, larger cartridges to be mounted in confined spaces such as under a sink.

In an embodiment of the device, the connecting head is insertable into the cavity in a direction of insertion, the receiving part is supported for movement in a plane parallel to the direction of insertion, and the movement includes at least a component corresponding to a displacement of the entire receiving part in the plane of movement.

This embodiment may be combined with the previous embodiment, so that the movement has both a component corresponding to a displacement of the entire receiving part in the plane of movement and a component corresponding to an intrinsic rotation of the receiving part about an axis perpendicular to the plane of movement. In any case, this embodiment is useful where the device is arranged in a row of similar devices and one of the cartridges in the middle is to be replaced. The displacement component allows this cartridge to be moved slightly out of the row, so that it is easier to grab hold of without the need to swivel it over a relatively large angle.

A variant of this embodiment includes a part for mounting the main part to a wall, wherein the direction of displacement has at least a component perpendicular to the wall.

This allows the device and cartridge to be positioned relatively close to the wall in the operative position of the cartridge. It can be moved away from the wall and then grabbed hold of when it is to be removed. In an embodiment of the device, at least one, e.g. all, of the ports of the receiving part are in respective sections of at least one wall having a surface at least partly delimiting the cavity laterally with respect to an axis corresponding to a direction of insertion of the connecting head into the cavity.

There is thus at least one port that does not face in the axial direction. This allows for the use of larger ports for a given diameter of the connecting head. Furthermore, it is not necessary to urge the cartridge in axial direction in order to ensure adequate sealing be- tween the ports of the cartridge and those of the receiving part. Also, where there are several ports, complicated coaxial arrangements at the axial end of the connecting head are avoided.

In a variant of this embodiment, in which the connecting head is insertable into the cavity in a direction of insertion, wherein the re- ceiving part is supported for movement in a plane parallel to the direction of insertion, the wall sections face a plane through a centre of the cavity and parallel to the plane of movement of the receiving part.

The main part will generally be mounted against a wall. The plane of movement will be perpendicular to the wall as a consequence. With the ports arranged in wall sections facing the plane through the centre of the cavity that is parallel to the plane of movement, the flow of liquid is parallel to the wall in the operational position of the cartridge. There are relatively few changes of direction of the liquid flow, so that the resistance to flow can be kept low. Also, the connecting head can be wider in a direction parallel to the plane of movement than in the direction perpendicular to it. Since the main part must in any case be large enough to accommodate the range of movement of the receiving part, the overall effect is to reduce the volume of the device.

In an embodiment of the device, the aperture has a shape deviating from a circular shape, e.g. an asymmetric shape with respect to a plane through a centre of the aperture and perpendicular to the aperture.

This embodiment is adapted for use with a connecting head having a matching shape. The aperture in the screening part can follow the cross-sectional shape of the connecting head quite closely. The asymmetric shape means that the connecting head cannot be inserted in every orientation about a cartridge axis aligned with the direction of insertion. This allows e.g. the ports of the cartridge to be positioned correctly with respect to those of the receiving part in view of the intended direction of flow. In a particular variant hereof, wherein the connecting head is in- sertable into the cavity in a direction of insertion and the receiving part is supported for movement in a plane parallel to the direction of insertion, the shape is asymmetric with respect to a plane transverse to the plane of movement. It will thus not be possible to insert a connecting head with a matching shape when rotated by 180° about a cartridge axis aligned with the direction of insertion when the connecting head is inserted into the cavity of the receiving part. The screening part will prevent this. In a particular embodiment, sections of an edge of the aperture forming a majority of its length are one of straight and curved with a centre of curvature on the side of the aperture with respect to the edge, and these sections are interrupted by at least one edge section forming a respective salient of the aperture.

The section forming a salient bounds a cove-shaped section of the aperture. Protruding parts on the connecting head such as bayonet lugs can be passed through these sections. Overall then, the edge of the aperture can be relatively close to the connecting head inserted through the aperture. This allows the screening device to play a role in aligning the cartridge or to catch liquid emerging from the cartridge when it is being removed.

In a variant of this embodiment, the edge of the aperture has two sections defining salients extending in opposite directions.

The protrusions on the connecting head may thus also extend in opposite directions. This allows them to function as pivots for a component of movement corresponding to swivelling of the cartridge, for example. The cartridge can in any case be held essentially parallel to the plane of movement.

In a variant of the embodiment in which sections of an edge of the aperture forming a majority of its length are one of straight and curved with a centre of curvature on the side of the aperture with respect to the edge, and these sections are interrupted by at least one edge section forming a respective salient of the aperture, the salients are mirror images with respect to a plane through a centre of the aperture, e.g. a plane parallel to a plane of movement of the receiving part. This helps prevent skewing. Where the plane is a plane parallel to the plane of movement of the receiving part, the protruding parts on the connecting head can move through or along guides on the main part, allowing the cartridge to be supported by the main part on opposite sides.

In an embodiment of the device, at least two ports of the receiving part are in respective side wall sections on opposite sides of the cavity.

The ports may have a relatively large cross-section without increas- ing the dimensions of the cavity. Also, inlets and outlet may be on opposite respective sides of the cavity, so that the flow of liquid need change direction less often.

In an embodiment, the screening part is guided for essentially purely translatory movement, e.g. in an essentially straight line. This allows for relatively uncomplicated journaling of the screening part. Also, the main part of the device can be kept relatively compact.

In an embodiment, the screening part is guided for movement along a trajectory in a plane of movement of the receiving part. This allows the screening part to move along a differently-shaped trajectory that that followed by the receiving part. Differences can be accommodated by allowing the cartridge to rotate in the aperture or move into or out of the aperture over a short distance.

In an embodiment, the screening part is guided for a movement maintaining its orientation with respect to the main part. The screening part can thus, for example, extend essentially in an approximately horizontal plane and remain horizontal as the receiving part moves with the connecting head. It can thus be used to collect liquid without the liquid being tipped out as the screening part moves. Instead, the liquid can evaporate over time.

In an embodiment of the device, the screening part is guided for movement by at least two pairs of an edge section and a protruding part movable along the edge section.

The edge section may be a section of an edge of a wall in which a slot is defined or a section of an edge of a ledge, for example. This manner of guidance does not require a permanent connection between the screening part and the main part, facilitating assembly. Also, a variant is made possible in which the screening part is arranged to slide into and out of the main part during its movement with the receiving part and the cartridge inserted through the aperture of the screening part. The main part of such a variant can be relatively compact.

In a variant of this embodiment, the protruding part corresponds to at least a section of a projecting rim extending along at least part of the edge section, e.g. a projecting rim forming a flange of the screening part.

The protruding part can be relatively thin, but still strong enough to support the screening part. The orientation of the screening part is maintained relatively well due to a relatively long line of contact be- tween the protruding part and the edge section. In a variant of the embodiment of the device in which the screening part is guided for movement by at least two pairs of an edge section and a protruding part movable along the edge section, the edge sections are provided by walls on either side of the screening part, e.g. walls of the main part, and each edge section adjoins one of a gate and a groove in the wall.

In a particular variant hereof, that one of a gate and a groove with which the wall is provided is open at at least one end to allow movement of the protruding part past the end concerned. The screening part can thus slide into and out of the main part like a drawer. The main part can be kept relatively compact in this way.

According to another aspect of the invention, which has independent significance, there is provided a device for forming a liquid treatment apparatus, e.g. a device as defined above, the device in- eluding :

a receiving part including a cavity arranged to receive a connecting head of a replaceable liquid treatment cartridge having at least one port in liquid communication with an interior of the liquid treatment cartridge, such that the at least one port(s) of the con- necting head are in sealed liquid communication with corresponding ports of the receiving part; and

at least one screening part,

wherein the at least one screening part(s) present(s) external surface sections at least on either side of an aperture through which the connecting head of a liquid treatment cartridge is insertable into the cavity, and

wherein the surface sections slope inwards towards the aperture. The positions on the surface sections closer to the aperture lie further inwards in the device. The device addresses the problem of facilitating insertion of the connecting head into the cavity of the receiving part. It can be implemented in such a way that the mouth of the cavity need not be visible to the user when mounting a replacement cartridge. The user need not crouch to mount the replacement cartridge. Nevertheless, the cartridge can be mounted in a position below the device without the need to provide for rotation of the receiving part over an angle large enough for the mouth of the cavity to be in view. In particular when the receiving part is supported for movement with respect to a main part of the device, the risk that the connecting head is inserted in a space in the main part adjacent the receiving part and provided to accommodate the movement of the receiving part is reduced. The screening part blocks such a space. The inward-sloping surface sections cause the connecting head to glide towards the aperture of the screening part when the connecting head contacts the screening part. The aperture is aligned or alignable with the cavity.

In an embodiment, the surface sections slope inwards up to an edge of the aperture.

There are thus no ridges that could impede movement of the connecting head along the surface sections.

In a particular variant of this embodiment, surface sections immediately adjacent to the edge of the aperture slope inwards in a direc- tion essentially perpendicular to the edge along at least a majority, e.g. the entirety of its length. An effect is to cause rotation of the cartridge when the connecting head and the aperture have a non-circular shape. In particular where the connecting head is provided with one or more protruding parts and the aperture includes correspondingly shaped sections at a salient to a majority of the edge of the aperture, the sloping surface sections also slope towards these sections immediately adjacent to them. Thus, then the protruding parts contact the surface around the aperture, they glide towards the aperture sections shaped to receive them.

In an embodiment, the surface sections are on an opposite side of a wall to correspondingly inclined surface sections of the wall spaced apart from and facing the receiving part.

The slope is thus caused by an inclined wall of essentially constant thickness. The screening part can therefore be relatively light. Moreover, an inclined surface faces the receiving part and is spaced apart from it. This allows the wall to form the bottom of a recess for catching and carrying away from the aperture drops of liquid escaping from the connecting head or the receiving part when the connecting head is retracted from the receiving part.

According to another aspect, the head part according to the invention for forming a liquid treatment apparatus includes at least two interconnected devices according to any one of the preceding claims.

This head part can be used to mount several cartridges. In this way, different kinds of treatment can be carried out in sequence on liquid passing through the head part. Alternatively or additionally, cartridges can be operated in parallel to increase the throughput of the liquid treatment apparatus.

In a variant of this embodiment, at least sections of surfaces of the respective screening parts of at least two of the interconnected de- vices have a different appearance, e.g . a different colour.

This provides information on which type of cartridge to be inserted into which of the at least two interconnected head part devices.

According to yet another aspect of the invention that has independ^¬ ent significance, there is provided a device for forming a liquid treatment apparatus, the device including a head part, e.g. a head part according to the invention, including :

at least one head part device, e.g. a head part device accord^¬ ing to any aspect of the invention as defined above,

the head part device including :

a receiving part including a cavity arranged to receive a con^¬ necting head of a replaceable liquid treatment cartridge having at least one port in liquid communication with an interior of the liquid treatment cartridge, such that the at least one port(s) of the con^¬ necting head are in sealed liquid communication with corresponding ports of the receiving part, and

at least one screening part, positioned in front of the receiving part,

the at least one screening part(s) defining an aperture through which the connecting head is insertable into the cavity, and

the at least one screening part(s) being spaced apart from the receiving part in at least one area adjacent the aperture; and

an arrangement for mounting the head part with the screening part below the receiving part, wherein the at least one screening part(s) includes at least one recess on a side proximal to the receiving part in at least one of the spaced-apart areas.

This device addresses a problem that can occur when a cartridge is removed upon use. The liquid in the cartridge is generally under pressure, which may not be relieved fully before the receiving part is disconnected from an outlet of the liquid treatment apparatus. Consequently, as the connecting head exits the cavity of the receiving part, a small amount of liquid may emerge from the ports of the connecting head. This liquid will enter the space between the receiving part and the screening part and drop down into the at least one recess provided in the screening part or parts. Due to the arrangement for mounting the head part with the screening part(s) below the receiving part, at least some of the liquid will drop down into the recess or recesses. There it will remain during subsequent use of a replacement cartridge. It can evaporate over time or the recess or recesses may be provided with a drain.

In an embodiment, at least one of the at least one recesses extends up to one of an edge of the aperture and an upstanding ridge form- ing the edge of the aperture.

The recess or recesses is or are thus positioned as closely adjacent to the connecting head as it moves through the aperture as possible. If there is a ridge around the aperture, then the recess or recesses extend to this ridge, which forms a side wall of the recess or recesses. If there is no ridge around the aperture, then the recess or recesses extend right up to the edge of the aperture. In an embodiment, the recess surrounds the aperture along a majority of a circumference of the aperture.

This has the effect of increasing the area of the recess and thus also the volume for a given depth. The recess can be shallower or the screening part(s) thinner. Liquid ports on the connecting head may be provided on more sides and liquid emerging from them when the cartridge is replaced be caught in the recess or recesses.

According to yet another aspect of the invention that has independent significance, there is provided a kit of parts for assembling a device for forming a liquid treatment apparatus, e.g. for assembling any device as defined above, including:

a main part;

a receiving part including a cavity arranged to receive a connecting head of a replaceable liquid treatment cartridge having at least one port in liquid communication with an interior of the liquid treatment cartridge, such that the at least one port(s) of the connecting head are in sealed liquid communication with corresponding ports of the receiving part,

a screening part for assembly with the main part in a position with respect to the receiving part enabling the screening part to screen off at least part of a space in which the receiving part is ar- ranged to move,

wherein the kit includes an arrangement for guiding the movement of the screening part, when assembled, with respect to the main part, at least when the connecting head is inserted in the cavity, wherein the guiding arrangement includes at least two pairs of an edge section and a protruding part movable along the edge sec^¬ tion, and

wherein members of the pairs with which the main part is pro- vided are arranged on opposite side of a space into which the screening part is insertable for assembly with the main part.

This kit addresses the problem of customising devices with a stand^¬ ard main part by means of a screening part. The main part and the receiving part can be assembled first, e.g . at a factory. The screen- ing part can be assembled to this sub-assembly at a later stage, e.g . just before the device leaves the factory or even at an installa^¬ tion site.

Because the screening part is suitable for assembly with the main part in a position with respect to the receiving part enabling the screening part to screen off at least part of a space in which the receiving part is arranged to move, foreign objects that could im^¬ pede the movement of the receiving part cannot easily enter this space. Because the kit includes an arrangement for guiding the movement of the screening part, when assembled, with respect to the main part, at least when the connecting head is inserted in the cavity, the screening part does not hinder movement of the car^¬ tridge with the receiving part. Because the guiding arrangement includes at least two pairs of an edge section and a protruding part movable along the edge section and members of the pairs with which the main part is provided are arranged on opposite side of a space into which the screening part is insertable for assembly with the main part, the screening part can be slid into a position of as^¬ sembly with the main part already completely assembled . In an embodiment of the kit, the edge sections are provided by walls on either side of the screening part in an assembled state of the device, e.g. walls of the main part, each edge section adjoins one of a gate and a groove in the wall, and that one of a gate and a groove with which the wall is provided is open at at least one end to allow movement of the protruding part past the end concerned.

The screening part can thus be arranged in the manner of a drawer. The main part can be relatively compact, since the screening part may protrude at certain positions along its range of movement with respect to the main part.

According to another aspect, the method according to the invention of assembling a device for forming a liquid treatment apparatus, e.g. of assembling a device according to the invention, includes: assembling a receiving part with a main part,

the receiving part including a cavity arranged to receive a connecting head of a replaceable liquid treatment cartridge having at least one port in liquid communication with an interior of the liquid treatment cartridge, such that the at least one port(s) of the connecting head are in sealed liquid communication with corresponding ports of the receiving part,

wherein, upon assembly with the main part, the receiving part is supported for movement with respect to the main part whilst the connecting head is inserted in the cavity;

providing a screening part for assembly with the main part in a position with respect to the receiving part enabling the screening part to screen off at least part of a space in which the receiving part is arranged to move,

wherein the screening part is assembled with the main part such that the screening part is guided for movement with respect to the main part, at least when the connecting head is inserted in the cavity, and

wherein the screening part is assembled to the main part subsequent to assembling the receiving part with the main part. The method provides essentially the same effects as the kit of parts according to the invention.

In an embodiment of the method, the screening part is assembled to the main part by sliding it into the main part.

Disassembly of the remainder of the device is therefore not re- quired. The screening part is assembled relatively easily to the rest of the device.

According to another aspect, the liquid treatment apparatus according to the invention includes at least one replaceable liquid treatment cartridge and a head part including at least one device accord- ing to the invention, e.g. a head part according to the invention.

In an embodiment of the liquid treatment apparatus, at least two, e.g. three or four, ports in liquid communication with an interior of the liquid treatment cartridge are provided in the connecting head of at least one of the at least one liquid treatment cartridges. This cartridge can therefore include a liquid treatment part including at least one membrane module arranged to operate in cross-flow mode. In that case, at least one port will serve as an outlet port for retentate, at least one as an outlet port for filtrate and at least one as an inlet port for liquid to be treated. In another variant, the cartridge can be arranged to provide multiple flow paths, one by- passing a liquid treatment part in the cartridge and joining the other downstream of that liquid treatment part. There would then be two inlet ports and at least one outlet port. There may also be multiple inlet ports or multiple outlet ports arranged to provide a passage for liquid having essentially the same composition. Such a configuration may help keep the resistance to flow relatively low, particularly if there are equal numbers of inlet and outlet ports.

In an embodiment of the liquid treatment apparatus, each liquid treatment cartridge has a cartridge axis, essentially aligned with the direction of insertion when the connecting head is inserted into the cavity, and at least one, e.g. all, of the ports of the connecting head of at least one of the at least one liquid treatment cartridges are provided in respective surface sections facing in directions at an angle to the cartridge axis. An effect is to allow larger ports to be provided without necessarily increasing the lateral dimensions of the connecting head. Furthermore, complicated concentric arrangements of ports facing in an axial direction are avoided.

In an embodiment of the liquid treatment apparatus, at least one, e.g. all, of the ports of the connecting head of at least one of the at least one liquid treatment cartridges is provided in an essentially planar respective surface section of the connecting head.

This helps provide for better sealing between the connecting head and the receiving part. Sealing elements surrounding the ports of the connecting head or the ports of the receiving part can be compressed relatively uniformly along their circumference. In an embodiment of the liquid treatment apparatus, each liquid treatment cartridge has a cartridge axis essentially aligned with the direction of insertion when the connecting head is inserted into the cavity, wherein the connecting head of at least one of the at least one liquid treatment cartridges and the receiving part of at least one of the at least one head part devices are provided with at least one set of alignment parts for axially aligning the cartridge axis with an axis of the receiving part corresponding to a direction of insertion, wherein each set includes a groove and at least one protruding alignment part for insertion into the groove when the connecting head is inserted into the cavity.

The aperture in the screening part of the associated head part device may have a complementary shape to that of the connecting head, e.g. accommodating the protruding alignment part or extend- ing into the groove, depending on which one of the alignment parts the connecting head is provided with. The protruding alignment parts for insertion into a groove may be arranged to contact the groove at multiple axial positions along the groove. In that case, the protruding part may have an elongated shape extending in axial direction, or there may be a set of protruding parts arranged in an axially oriented row. The set of alignment parts ensures that the ports of the connecting head are aligned with those of the receiving part and that the connecting head meets with relatively little resistance when it is being inserted. The risk of damage to any seal- ing parts provided on the connecting head or inside the cavity of the receiving part is kept relatively low. The screening part need not be positioned precisely and in fixed relationship to the receiving part, since the alignment parts carry out the alignment. In an embodiment of the liquid treatment apparatus, at least one protruding part is provided on the connecting head of at least one of the at least one liquid treatment cartridges, and the aperture of the screening part of at least one of the at least one head part de- vices has a complementary shape to that of a section of the connecting head including the protruding part(s).

There is thus a relatively low likelihood of foreign objects or liquid passing between the connecting head and the screening part. The protruding parts can fulfil functions such as orienting the cartridge about an axis thereof aligned with the direction of insertion into the receiving part, retaining the cartridge in locked position to the head part device and aligning the cartridge with the receiving part.

In an embodiment of the liquid treatment apparatus, at least a section of an edge of the aperture of the screening part of at least one of the at least one head part devices is arranged to contact the connecting head of at least one of the at least one liquid treatment cartridges when inserted into the receiving part.

This also helps keep the likelihood of foreign objects or liquid passing between the connecting head and the screening part relatively low. Moreover, the connecting head can move the screening part, where it is arranged to move with the receiving part and the connecting head. Also, the aperture may have a rotationally asymmetric shape to ensure that the cartridge is inserted with the correct orientation about a cartridge axis aligned with the direction of inser- tion during insertion. The invention will be explained in further detail with reference to the accompanying drawings, in which :

Fig. 1 is a perspective view of a liquid treatment apparatus including a head part with three interconnected head part devices into which a respective one of three replaceable liquid treatment cartridges is inserted;

Fig. 2 is a perspective view of a connecting head of one of the liquid treatment cartridges;

Fig. 3 is a side plan view of the connecting head;

Fig. 4 is a side plan view of the connecting head from an opposite direction to that of Fig. 3;

Fig. 5 is a side plan view of the liquid treatment apparatus with the liquid treatment cartridge in an operative position;

Fig. 6 is a side plan view of the liquid treatment apparatus with the liquid treatment cartridge in a position in which it can be withdrawn from the head part device in which it is received;

Fig. 7 is a first perspective view of one of the head part devices with part of its housing removed;

Fig. 8 is a second perspective view of the head part device with the housing part removed;

Fig. 9 is a first side plan view into an interior of the head part device, showing a receiving part of the head part device in a first position;

Fig. 10 is a second side plan view into the interior of the head part device, this time showing the receiving part in a second position;

Fig. 11 is a perspective view into the interior of the head part device, but with the receiving part removed; Fig. 12 is a perspective view of a housing part of the head part device;

Fig. 13 is a perspective view of a further component of a housing of the head part device;

Fig. 14 is a perspective view of the receiving part shown in

Figs. 9 and 10;

Fig. 15 is a first perspective view into a cavity of the receiving part;

Fig. 16 is a second perspective view into a cavity of the receiv- ing part;

Fig. 17 is a perspective view of a cartridge recognition component for customising the head part device;

Fig. 18 is a first perspective view of a screening part forming part of the head part device;

Fig. 19 is a second perspective view of the screening part; Fig. 20 is a top plan view of the screening part; and

Fig. 21 is a perspective view of an alternative screening part.

In the following a liquid treatment apparatus 1 (Fig. 1) for the treatment of aqueous liquids such as mains drinking water will be described. The liquid treatment apparatus 1 includes a head part 2 and three replaceable liquid treatment cartridges 3-5. The head part 2 includes three head part devices 6-8. The head part devices 6-8 are each configured to receive a liquid treatment cartridge 3-5 in an operative position, such that liquid to be treated is led into the cartridge 3-5, treated in its interior and returned to the head part device 6. The head part devices 6-8 are interconnected. The head part devices 6-8 may be arranged in parallel or in series in flow sense, or in a combination thereof. A parallel arrangement of two of the head part devices 6-8 may be arranged in series with a third of the head part devices 6-8, for example. Here, the head part devices 6-8 will be assumed to be arranged in series.

It is also possible for a fraction of the liquid to bypass a particular one of the liquid treatment cartridges 3-5 or to bypass one or more liquid treatment sections arranged in the interior of the liquid treatment cartridge 3-5. In that case, a flow divider (not shown in detail) may be arranged in the head part device 6-8 concerned. The flow divider may be a variable-ratio flow divider to enable the fraction bypassing the liquid treatment section(s) to be adjusted. The head part devices 6-8 have the same basic shape and configuration, which will be described with reference to a downstream head part device 6. The liquid treatment cartridges 3-5 have housings which also have the same basic shape and configuration. They will generally differ as to the liquid treatment sections contained in them, however.

They may, for example, include a liquid treatment section comprising a membrane filtration module, e.g. for microfiltration, ultrafiltration or reverse osmosis treatment. They may also or alternatively include a liquid treatment section including a liquid treatment medi- urn for treatment of liquid contacting it in a diffusive process. This includes sorption and elution. Sorption for present purposes includes treatment by ion exchange. The liquid treatment cartridge may include a bed of ion exchange resin, for example. A particular example is weakly acidic cation exchange resin at least partially in the hydrogen form for reducing the carbonate hardness of water. A liquid treatment cartridge may include multiple liquid treatment sections or a liquid treatment section including multiple liquid treatment media, e.g. a bed of ion exchange resin mixed with activated carbon. Another type of liquid treatment cartridge may include a depth filter or polishing filter.

Although the liquid treatment cartridges 3-5 will thus generally be configured to carry out different treatments or the same treatment to a different extent, the housings are of essentially the same shape. Visible indicia may be provided to allow them to be distinguished from each other. These may be replicated on at least sections of the respective head part devices 6-8 to enable a user to allocate the correct liquid treatment cartridge 3-5 to the correct head part device 6-8, as will be explained. As an example, colour coding of at least a section of a surface of the cartridge housing and at least a section of a surface of a part of the head part devices 6-8 can be used. In the illustrated embodiment, a keying system is employed to make it impossible to place a liquid treatment

cartridge 3-5 in an operative position in the wrong head part device 6-8.

The basic configuration of the liquid treatment cartridges 3-5 will be explained with reference to a liquid treatment cartridge 3 at the downstream end of the liquid treatment apparatus 1.

The liquid treatment cartridge 3 (Figs. 2-4) is of the type described more fully in international patent application

No. PCT/EP2015/050155 of 7 January 105, the contents of which are hereby incorporated by reference. It has a housing including a vessel 9 closed at its mouth by a cap-shaped part including a connecting head 10. The cap-shaped part and the vessel 9 may be bonded to each other, e.g. by welding, for example ultrasonic welding. It is possible to define a cartridge axis 11 (Figs. 3,4) , generally corresponding to a longitudinal axis of the cartridge 3, except if it is very short. It extends through the connecting head 10 and an opposite end (not shown) of the cartridge housing. The connecting head 10 is provided with four liquid-permeable cartridge ports 12-15 in liquid communication with an interior of the cartridge 3. First and second ports 12, 13 (Fig. 4) are provided in a first surface section 16 facing in a direction at an angle to the cartridge axis 11 such that the connecting head 10 tapers towards the axial end of the cartridge 3 at which the connecting head 10 is provided. Third and fourth cartridge ports 14, 15 (Fig. 3) are provided in a second surface section 17 facing in a direction at an angle to the cartridge axis 11 such that the connecting head 10 tapers towards the axial end of the cartridge 3 at which the connecting head 10 is provided. The first and second surface sections 16, 17 are on opposite sides of the connecting head 10. The first and second cartridge ports 12, 13 on the one hand and the third and fourth cartridge ports 14, 15 are thus also provided on opposite sides of the connecting head 10. Each is aligned with a respective other cartridge port 12-15 on the opposite side of the connecting head 10 in this example.

Each cartridge port 12-15 is surrounded by a respective sealing element 18-21. The first and second surface sections 16, 17 are essentially planar. The sealing elements 18-21 are thus compressed relatively uniformly, when the connecting head 10 is inserted into the head part device 6.

Because the cartridge ports 12-15 are provided in lateral surfaces of the connecting head 10 with respect to the cartridge axis 11, they can have a relatively large cross-section, given the lateral dimensions of the connecting head 10.

A first alignment ridge 22 (Fig. 4) is provided adjacent the first and second cartridge ports 12, 13. A second alignment ridge 23 (Fig. 3) is provided adjacent the third and fourth cartridge ports 14, 15.

Both alignment ridges 22,23 have an elongated shape essentially parallel to the cartridge axis 11. They are each other's mirror image with respect to a plane containing the cartridge axis 11. However, they are offset with respect to a further plane perpendicular to that plane and containing the cartridge axis 11.

The alignment ridges 22,23 protrude laterally from the connecting head 10.

Axial ends 24,25 distal to the axial end of the cartridge 3 at which the connecting head 10 is provided are rounded. The cartridge 3 is supported and retained by these ends 24,25 in at least an operative position in the head part device 6.

In the illustrated embodiment, the connecting head 10 is provided with an inlay 26 (Fig. 2) forming part of the keying system mentioned above. Further details are provided in European patent ap- plication No. 15183505.5 of 2 September 2015, the contents of which are hereby incorporated by reference. The inlay 26 is provided with a feature, in this case a slot 27, of which at least one of the position and the shape is associated with the type of the cartridge 3. The inlay 26 is arranged in a recess or rebate formed in the connecting head 10. The inlay 26 is irreversibly joined to the connecting head 10 in this example. It may be joined by bonding, e.g. adhesive bonding or welding, for example ultrasonic welding. The inlay 26 may be colour-coded, e.g. having a colour different from that of a remainder of the connecting head 10.

If the cartridges 3-5 are each arranged to carry out a different liquid treatment or at least a particular liquid treatment to a different extent, at least two will be provided with a different inlay 26. The inlays will differ at least in terms of at least one of the shape, size and position of at least one external feature. They may, as mentioned, differ in terms of their colour as well. The connecting heads 10 are otherwise, at least externally, identical in shape. The head part device 6 includes a main part including left and right housing parts 28,29. These are connected to an (optional) mounting plate 30 (Fig. 5). The housing parts 28,29 are themselves also provided with sections with features for mounting the main part to a wall (not shown). In the illustrated embodiments, these sections include holes 31,32 through which screws or similar fasteners for attaching the main part to the wall can be passed.

The head part device 6 further includes a receiving part 33

(Figs. 14-16), a latching device 34 (Figs. 7-11) and a screening part 35 (Figs. 18-20). The left and right housing parts 28,29 define a housing cavity, in which the receiving part 33 is arranged to move. The housing leaves the housing cavity open on one side, which is the underside in use. The screening part 35 extends across this opening.

In the illustrated embodiment, the latching device 34 is arranged within the housing cavity to arrest movement of the receiving part 33 in a first position thereof with respect to the main part. The receiving part 33 defines a cavity having a mouth through which the connecting head 10 is insertable into the cavity. It is possible to define a receiving part axis 36 (Fig. 14), which is essentially aligned with the direction of insertion, and thus with the car- tridge axis 11 when the connecting head 10 is inserted.

The cavity has a shape corresponding to that of the connecting head 10. It thus tapers in axial direction towards an end opposite the mouth of the cavity.

Liquid-permeable ports 37-40 are provided in opposing side walls bounding the cavity. First and second ports 37,38 are provided in a first side wall section 41. Third and fourth ports 39,40 are provided in a second side wall section 42. The first and second side wall sections 41,42 are essentially planar.

When the connecting head 10 is inserted into the cavity to an in- tended extent, the cartridge ports 12-15 are in sealed liquid communication with respective ones of the receiving part ports 37-40. The sealing elements 18-21 of the connecting head 10 are compressed by the first and second side wall sections 41,42. They isolate the flows of liquid and essentially prevent leakage into the cavi- ty. Due to the taper of the connecting head 10 and the corresponding inclination of the side wall sections 41,42, the sealing

elements 18-21 only contact the side wall sections 41,42 towards the end of the inserting movement.

When the (correct) connecting head 10 has been inserted far enough to place the ports 12-15 of the cartridge 3 in sealed liquid communication with those of the receiving part 33, the receiving part 33 is movable, with the connecting head 10 inserted, between the first position (Figs. 6 and 9) and a second position (Figs. 5 and 10).

The movement of the receiving part 33 is along a trajectory in a plane of movement essentially parallel to the receiving part axis 36. The movement includes both a component corresponding to a displacement of the entire receiving part 33 in the plane of movement and a component corresponding to an intrinsic rotation about an axis perpendicular to the plane of movement. The intrinsic rotation corresponds to a change in angle of the receiving part axis 36 rela- tive to the vertical.

The displacement corresponds to a displacement of the axis of rotation and thus of the entire receiving part 33. This displacement is in a direction transverse to the wall to which the head part 2 is configured to be mounted (cf. Figs. 5 and 6). This has the effect that it is also transverse to a row in which the head part devices 6-8 are aligned. The cartridge 3 thus both swivels and moves out of the row and away from the wall as the receiving part 33 is moved from the second to the first position. It is therefore easy to grab hold of in the first position, even if it is relatively close to the wall or an adjacent cartridge 4 in the second position. Nevertheless, the cartridge 3 need not be swivelled over a relatively large angle. An angle of 25° or less, e.g. 15° or less may suffice.

The receiving part 33 is provided with protrusions 43-46 arranged to move along guides. The protrusions 43-46 are provided on opposite sides of the receiving part 33. They protrude in opposite directions transverse to the plane of movement of the receiving part 33. The guides are formed by edges of features of the housing of the main part of the head part device 6. These include edges of slots 47-50. The connecting head 10 is insertable into and retractable from the cavity in the receiving part 33 only in the first of the first and second positions of the receiving part 33 with respect to the main part. It is locked to the main part in the second position. This is because the left and right housing parts 28,29 are provided with

ledges 51,52 that define support surfaces 53,54 and have ends defining one side of a respective channel 55,56 through which at least a section of a respective one of the alignment ridges 22,23 is movable only in the first of the first and second positions.

In the first position, the channels 55,56 are essentially aligned with first and second alignment grooves 57,58 of the receiving part 33. The alignment grooves 57,58 extend essentially in parallel direction to the receiving part axis 36. They are arranged to receive the alignment ridges 22,23 on the connecting head 10 of the cartridge 3. To this end, the alignment grooves 57,58 are open in axial direction at a longitudinal end proximal to the mouth of the cavity defined by the receiving part 33.

When the receiving part 33 is in the first position and the connecting head 10 is inserted, the ends 24,25 of the alignment

ridges 22,23 move past the ends of the ledges 51,52 to the level of the support surfaces 53,54. As the receiving part 33 moves towards the second position, the cartridge 3 is supported by the ends 24,25 of the alignment ridges 22,23 resting on the support surfaces 53,54. The main part of the head part device 6 thus carries the weight of the cartridge 3.

The support surfaces 53,54 are angled and the trajectory of movement of the receiving part 33 is such that an axial distance (with respect to the receiving part axis 36) between the point of contact with the support surface 53,54 and an axial end of the cavity in the receiving part 33 opposite its mouth decreases as the receiving part 33 moves towards the second position. This forces the connecting head 10 further into the cavity in the receiving part 33.

The second position is reached when the ends 24,25 of the alignment ridges 22,23 are caught by detents 59,60 in the support surfaces 53,54. The cartridge 3 thus holds the receiving part 33 in the second position.

In the second, operative position, the ports 37-40 of the receiving part 33 are in sealed liquid communication with respective

ports 61-64 of the main part of the head part device 6. These ports 61-64 are open to the housing cavity in which the receiving part 33 is arranged to move and provided in opposing side walls. Sealing elements 65-68 isolate the flows of liquid between the ports 37-40,61-64.

In the illustrated embodiment, the ports 61-64 of the main part of the head part device 6 are defined by separate housing interior parts 69,70 assembled to the left and right housing parts 28,29 on the inside thereof. In an alternative embodiment, they are defined by the left and right housing parts 28,29 directly.

In each case, the ports 61-64 are at least placeable in liquid communication with a liquid inlet (not shown) or a liquid outlet 71 of the head part device 6. They may be in permanent liquid communication or a flow regulating device may be used to place them in liquid communication. Thus, in the second position, liquid may, for example, flow through first and second housing part ports 61,62, then through first and second receiving part ports 37,38 and first and second cartridge ports 12, 13 into the interior of the cartridge 3. The liquid leaves the cartridge 3 through third and fourth cartridge ports 14, 15, passes through third and fourth receiving part ports 39,40 and then through third and fourth housing part ports 63,64.

When the receiving part 33 is in the first position, the housing part ports 61-64 are aligned with and in sealed liquid communication with ports 72-75 at the ends of channels defined in the receiving part 33. The channels connect the first housing part port 61 with the third housing part port 63 and the second housing part port 62 with the fourth housing part port 64. In an alternative embodiment, at least one of the housing part ports 61-64 is connected with a larger number of the other housing part ports 61-64 than just one, so that there can be fewer channels, e.g. just one. The channels form a bypass, so that the flow of liquid through the head part device 6 is not blocked in the absence of a cartridge 3 (when the receiving part 33 is in the first position).

The receiving part ports 37-40, on the other hand, are blocked by the wall in which the housing part ports 61-64 are provided when the receiving part 33 is in the first position.

The receiving part 33 is provided with surrounding sealing

elements 76,77 that prevent leakage into the housing cavity during movement of the receiving part 33 between the first and second positions. Each surrounds all receiving part ports on one of two opposite sides of the receiving part 33 and remains in contact with a respective interior surface of the housing part in which the housing part ports on that side are provided. These will also be surrounded by the sealing elements 76,77.

The latching device 34 is arranged releasably to hold the receiving part 33 in the first position, at least in the absence of the connect- ing head 10. The latching device 34 is a single resilient, essentially U-shaped insert having pawls 78,79 at respective free ends of its arms 80,81. Part of the receiving part 33 is received between the arms 80,81 in the first position. In that position, the pawls 78,79 engage the receiving part 33 in the absence of the connecting head 10. The connecting head 10 forces the latching device 34 out of engagement with the receiving part 33 when inserted into the cavity of the receiving part 33. In the illustrated embodiment, the protruding alignment ridges 22,23 are arranged to contact the pawls 78,79 to release the receiving part 33. The screening part 35 is positioned in front of the receiving part 33 from the perspective of the connecting head 10 when the connecting head 10 is inserted. It closes off the housing cavity in which the receiving part 33 is arranged to move, but includes an

aperture 82 through which the connecting head 10 can be inserted into the cavity of the receiving part 33. The screening part 35 is movable, so that the aperture 82 can remain aligned in the direction of the receiving part axis 36 with the mouth of the cavity. In the illustrated embodiment, the connecting head 10 effects the alignment. The receiving part 33 includes at least one, in this case two, protruding retaining parts 83,84 that engage the screening part 35 in the first position. In the illustrated embodiment, they contact a ridge 85 defining an edge of the aperture 82 on a side of the screening part 35 facing the receiving part 33. In the absence of the connecting head 10, the receiving part 33 is held by the latching device 34 and in turn prevents movement of the screening part 35 from the first position towards the second position. The screening part 35 is provided with a lip 86 along an edge transverse to its direction of movement. This lip 86 is occluded by the left and right housing parts 28,29 in the second, operative position, but exposed in the first position. The visible surface of the lip 86, in this case, the upper surface, is provided with at least one indici- urn, e.g. in the form of a specific colour. The colour may be different from that of a remainder of the screening part 35. In an alternative embodiment, the colour is the same. The colour is associated with the type of cartridge 3 intended to be inserted into the head part device 6. It may correspond to the colour of the inlay 26, for example. Thus, at least two of the head part devices 6-8 may include screening parts 35 of which at least the surface sections of the respective lips 86 exposed in the first position have a different colour. Symbols or patterns may be used as distinguishing indicia in an alternative embodiment. The screening part 35 is guided for movement by sections 87,88 of a flange extending around its edge. These sections are on opposite sides of the screening part 35 and essentially straight. They are received in grooves 89,90 on the inside of depending wall

sections 91,92 of the left and right housing parts 28,29 on either side of a space for receiving the screening part 35. The

grooves 89,90 are open at the end distal to the end configured for mounting the head part 2 to the wall. The straight-line movement allows the head part device 6 to be relatively compact, since the depending wall sections 91,92 need not be very high.

It is noted that the head part device 6, indeed the head part 2 can be assembled without the screening part 35 at first. This involves assembling the housing with the receiving part 33 arranged therein. Subsequently, e.g. when the head part 6 is to be installed or finalised for leaving a factory, it can be customised by inserting a screening part 35 of which the surface of the lip 86 has a selected one of several alternative appearances.

At this time, the head part device 6 can further be customised by inserting a cartridge recognition component 93 complementary in shape to the inlay 26 through an aperture 94 in the right housing part 29 into a position from which it can only be removed by disassembling the head part device 6. The cartridge recognition component 93 includes a protrusion 95 that faces in a direction parallel to the plane of movement of the receiving part 33 when the cartridge recognition component 93 has been combined with the remainder of the main part of the head part device 6. A window 96 in the receiving part 33 allows the cartridge recognition component 93 to engage the connecting head 10 when the latter is inserted into the cavity of the receiving part in the first position. In the illustrated embodiment, the protrusion 95 enters the slot 27 in the inlay 26 when the connecting head 10 is inserted into the cavity defined by the receiving part 33. Further details are provided in the above- mentioned European patent application No. No. 15183505.5 of 2 September 2015. A further effect of the straight-line movement of the screening part 35 is that it retains its orientation during movement. This is relevant with regard to a further function it fulfils, which is to catch small amounts of liquid that may leak from the cartridge 3 when it is retracted in the first position after use. A recess 97 is defined on a side of the screening part 35 proximal to the receiving part 33. In the illustrated embodiment, the recess 97 surrounds the aperture 82 along a majority of the circumference of the aperture, but not quite totally. The recess 97 is interrupted by a rib 98. The rib 98 may serve as a reinforcement. It may also be hollow to engage a protruding part of the cartridge 3 in at least a position of the screening part 35 corresponding to the first position of the receiving part 33. The recess extends up to the ridge 85 forming the edge of the aperture 82. The aperture 82 also has a shape complementary to that of the connecting head 10, so that most of the liquid will be caught in the recess 97. After a new cartridge 3 has been inserted into the head part device 6 and the receiving part 33 moved to the second position, any liquid caught in the recess 97 can evaporate over the period of use of the new cartridge 3. A surface section of the screening part 35 forming a bottom of the recess 97 slopes away from the receiving part 33 (downwards) with increasing distance from the aperture. Thus, liquid is carried away from the aperture 82. Moreover, the recess can be relatively shallow adjacent the aperture. The aperture 82 thus traverses the screening part 35 over a relatively short distance. This gives the connecting head 10 more room to swivel, even though the shape of the aperture 82 matches the shape of the connecting head 10 relatively closely. The surface sections forming the bottom of the recess 97 are on the opposite side of a wall forming part of the screening part 35 to correspondingly inclined surface sections that face away from the head part device 6. In use, with the head part 2 mounted to a wall, these surface sections are on the underside of the screening part 35. They slope inwards towards the aperture 82. This allows them to guide the connecting head 10 of a cartridge 3 to be inserted towards the aperture 82. A user need not bend down or squat to look at the head part 2 when mounting the cartridge 3 to the head part device 6.

The inclined exterior surface sections, together with the shape of the aperture 82, also serve to ensure that the connecting head 10 is inserted with the correct orientation about the cartridge axis 11. First, the aperture 82 has a shape deviating from a circular shape. Indeed, an edge of the aperture 82 has essentially straight edge sections 99, 100, matching the essentially planar surface sections 16, 17 of the connecting head 10. These edge sections 99, 100 may be essentially parallel to the direction of movement of the screening part 35, to facilitate swivelling of the cartridge 3 in a plane parallel to the opposing essentially straight edge

sections 99, 100, as in the illustrated embodiment. The majority of the remainder of the edge of the aperture 82 is curved, with the centre of curvature lying on the side of the edge on which the aperture is. That is to say that these edge sections are concave, seen from the aperture 82. However, the curvature changes sign at certain locations, such that cove-shaped sections 101, 102 of the aperture 82 are defined. These cove-shaped sections 101, 102 form salients with respect to the major part of the aperture 82. They extend in opposite directions and are provided to accommodate the align- ment ridges 22,23 when the connecting head 10 is inserted through the aperture 82. This is a second feature helping to ensure that the connecting head 10 can only be inserted with a relatively precisely defined orientation about the cartridge axis 11.

Because the inclined surface sections are inclined towards the edge everywhere along the edge, including along the sections defining the cove-shaped sections 101, 102 of the aperture 82, it is relatively easy to "find" the aperture 82 without looking at it when inserting the connecting head 10. Upper ends of the alignment ridges 22,23 glide along the inclines surface sections in a direction transverse to the cartridge axis 11. The screening part 35 is held in place by the receiving part 33 and the latching device 34 whilst this happens.

The above-mentioned effects are also realised with an alternative screening part 35', which differs primarily in having integral latching devices 103, 104 for engaging the main part of the head part device 6 in either or both of the first and second positions. A separate feature 105 is also provided for engaging a variant (not shown) of the receiving part 33 having a single protrusion instead of the two retaining parts 83,84. This protrusion falls into the engagement feature 105 in the first position. The alternative screening part 35' thus replaces or enhances the effects of either or both of the latching device 34 and the detents 59,60 in this embodiment.

The invention is not limited to the embodiments described above, which may be varied within the scope of the accompanying claims. For example, it is also possible to provide a screening part that is guided for rotary movement in an essentially horizontal plane, in use. Such a variant would be combined with a rotary receiving part. Also, a variant of the screening part 35 of the embodiment of Figs. 5-20 may have multiple, e.g. two, features corresponding to the feature 105 of the screening part 35' shown in Fig. 20. These features receive the retaining parts 83,84 when the receiving part 33 is in the first position. The screening part 35 is held relatively securely in this variant.

List of reference numerals

1 - liquid treatment apparatus

2 - head part

3 - downstream cartridge

4 - middle cartridge

5 - upstream cartridge

6 - downstream head part device

7 - middle head part device

8 - upstream head part device

9 - vessel

10 - connecting head

11 - cartridge axis

12 - 1^st cartridge port

13 - 2^nd cartridge port

14 - 3^rd cartridge port

15 - 4^th cartridge port

16 - 1^st cartridge surface section

17 - 2^nd cartridge surface section

18 - 1^st cartridge sealing element

19 - 2^nd cartridge sealing element

20 - 3^rd cartridge sealing element

21 - 4^th cartridge sealing element

22 - 1^st alignment ridge

23 - 2^nd alignment ridge

24 - curved end of 1^st alignment ridge

25 - curved end of 2^nd alignment ridge

26 - inlay

27 - inlay slot

28 - left housing part right housing part

mounting plate

left screw hole

right screw hole

receiving part

latching device

,35' screening part

receiving part axis

1^st receiving part port

2^nd receiving part port

3^rd receiving part port

4^th receiving part port

1^st side wall section

2^nd side wall section left upper protrusion left lower protrusion right upper protrusion right lower protrusion upper left housing part slot lower left housing part slot upper right housing part slot lower right housing part slot left ledge

right ledge

left support surface right support surface left channel

right channel

1^st alignment groove

2^nd alignment groove left detent

right detent

1^st housing part port

2^nd housing part port

3^rd housing part port

4^th housing part port

1^st sealing element on housing

2^nd sealing element on housing

3^rd sealing element on housing

4^th sealing element on housing left housing interior part right housing interior part liquid outlet

1^st bypass port

2^nd bypass port

3^rd bypass port

4^th bypass port

1^st receiving part sealing element

2^nd receiving part sealing element left pawl

right pawl

left arm

right arm

aperture

1^st retaining part

2^nd retaining part

ridge

lip

left flange section

right flange section left groove

right groove

left depending wall section right depending wall section cartridge recognition component housing part aperture

protrusion on cartridge recognition component

window in receiving part

screening part recess

screening part rib

left straight edge section

right straight edge section left cove-shaped aperture section right cove-shaped aperture section left latching device

right latching device

engagement feature

Claims

Device for forming a liquid treatment apparatus (1), including :

a main part;

a receiving part (33) including a cavity having a mouth, wherein the cavity is arranged to receive through the mouth a connecting head (10) of a replaceable liquid treatment cartridge (3-5) having at least one port (12-15) in liquid communication with an interior of the liquid treatment

cartridge (3-5), such that the at least one port(s) (12-15) of the connecting head (10) are in sealed liquid communication with corresponding ports (37-40) of the receiving part (33), wherein the receiving part (33) is supported for movement with respect to the main part whilst the connecting head (10) is inserted in the cavity; and

a screening part (35;35'),

wherein the screening part (35;35') is provided with an aperture (82;82'),

wherein the screening part (35;35') is positioned in front of the receiving part (33), and

wherein the screening part (35;35') is guided to enable movement with respect to the main part with the

aperture (82;82') aligned with the mouth.

Device according to claim 1,

wherein the main part includes a housing defining a housing cavity in which the receiving part (33) is arranged to move, and

wherein the screening part (35;35') extends across a mouth of the housing cavity. Device according to claim 1 or 2,

arranged to allow movement of the connecting

head (10) into and out of the cavity in a first of first and second positions of the receiving part (33) and to prevent such movement in the second position.

Device according to claim 3,

wherein the main part includes at least one

section (51,52) defining a support surface (53,54) for supporting a protruding part (22,23) of the liquid treatment cartridge (3,4,5) during movement of the receiving part (33) be tween the first and second positions with the connecting head (10) inserted.

Device according to claim 4

wherein the support surface (53,54) includes a

detent (59,60) for arresting movement of the protruding part (22,23) along the support surface (53,54).

Device according to claim 4 or 5,

wherein the support surface (53,54) is provided by a ledge (51,52).

Device according to claim 6,

wherein an end of the ledge (51,52) borders a

channel (55,56) for receiving the protruding part (22,23) of the liquid treatment cartridge (3,4,5) in the first position of the receiving part (33). Device according to any one of claims 4-7,

wherein the receiving part (33) has an axis (36) corresponding to a direction of insertion of the connecting head (10) into the cavity, and

wherein an axial distance of the support surface (53,54) to an axial end of the cavity distal to the mouth decreases towards the second position over at least a section of the support surface (53,54).

Device according to any one of claims 3-8,

wherein the screening part (35;35') includes a surface section provided with at least one indicium, occluded in only one of the first and second positions, e.g. by the main part.

Device according to any one of claims 3-9,

wherein the screening part (35;35') and the receiving part (33) are arranged to engage each other in at least one of the first and second positions, such that one arrests movement of the other in at least one direction, e.g. in a direction corresponding to movement towards the other of the first and second positions, and

wherein the device includes at least one latching device (34; 103, 104) on one of the main part and the arresting one of the screening part (35;35') and the receiving

part (33), the latching device arranged releasably to restrain movement of the arresting one of the screening part (35;35') and the receiving part (33) in one of the first and second positions. Device according to claim 10,

wherein at least one of the latching devices (103, 104) is an integral part of the screening part (35')-

Device according to any one of the preceding claims,

included in a head part (2) including at least one further device (7,8) according to any one of the preceding claims, wherein the screening parts (35;35') of the device and the further device (7,8) include corresponding surface sections differing in appearance.

Device according to any one of the preceding claims,

wherein the screening part (35;35') includes a surface section provided with at least one indicium in the form of a colour contrasting with a colour of a majority of a remainder of the screening part (35;35')-

Device according to any one of the preceding claims,

wherein the main part includes at least one of at least one inlet and at least one outlet (71), at least one of which is placeable in liquid communication with at least one respective one of the ports (37-40) of the receiving part (33) in at least one position of the receiving part (33) with respect to the main part.

Device according to claim 14,

wherein the receiving part (33) is movable between a first and a second position with respect to the main part, and wherein the device further includes a valve mechanism for interrupting the liquid communication in only the first of the first and second positions.

16. Device according to claim 15,

wherein the receiving part (33) is arranged to function as a movable valve member of the valve mechanism, and wherein at least one, e.g. all of the ports (37-40) of the receiving part (33) are aligned in the second position with respective ports (61-64) of the main part in only the second of the first and second positions.

17. Device according to claim 15 or 16,

wherein at least one channel is formed in the receiving part (33), and

wherein the main part includes at least one first port (61,62) at least placeable in liquid communication with at least one of the at least one inlets,

wherein the main part includes at least one second port (63,64) at least placeable in liquid communication with at least one of the at least one outlets (71), and

wherein the channel is arranged, in at least the first position of the receiving part (33), to place at least one of the at least one first ports (61,62) in liquid communication with at least one of the at least one second port (63,64).

18. Device according to any one of the preceding claims,

wherein the receiving part (33) is supported for movement by protrusions (43-46) arranged to move along guides.

19. Device according to claim 18,

wherein the protrusions (43-46) are provided on the receiving part (33). Device according to claim 18 or 19,

wherein the protrusions (43-46) are provided on opposite sides of the receiving part (33), and

wherein the protrusions (43-46) protrude in opposite directions generally transverse to a plane in which the receiving part (33) is arranged to move.

Device according to any one of the preceding claims,

wherein the connecting head (10) is insertable into the cavity in a direction of insertion,

wherein the receiving part (33) is supported for movement in a plane parallel to the direction of insertion, and wherein the movement includes at least a component corresponding to an intrinsic rotation of the receiving part (33) about an axis perpendicular to the plane of movement.

Device according to any one of the preceding claims,

wherein the receiving part (33) is supported for movement in a plane parallel to the direction of insertion, and wherein the movement includes at least a component corresponding to a displacement of the entire receiving part (33) in the plane of movement.

Device according to claim 22,

including a part (30-32) for mounting the main part to a wall,

wherein the direction of displacement has at least a component perpendicular to the wall. Device according to any one of the preceding claims, wherein at least one, e.g. all, of the ports (37-40) of the receiving part (33) are in respective sections of at least one wall having a surface (41,42) at least partly delimiting the cavity laterally with respect to an axis (36) corresponding to a direction of insertion of the connecting head (10) into the cavity.

Device according to claim 24 and any one of claims 21-23, wherein the wall sections face a plane through a centre of the cavity and parallel to the plane of movement of the receiving part (33).

Device according to any one of the preceding claims,

wherein the aperture (82;82') has a shape deviating from a circular shape, e.g. an asymmetric shape with respect to a plane through a centre of the aperture (82;82') and perpendicular to the aperture (82;82').

Device according to claim 26 and any one of claims 21-25, wherein the shape is asymmetric with respect to a plane transverse to the plane of movement.

Device according to any one of the preceding claims,

wherein sections (99, 100) of an edge of the

aperture (82;82') forming a majority of its length are one of straight and curved with a centre of curvature on the side of the aperture (82;82') with respect to the edge, and

wherein these sections (99, 100) are interrupted by at least one edge section forming a respective salient (101, 102) of the aperture (82;82'). Device according to claim 28,

wherein the edge of the aperture (82;82') has two sections defining salients (101, 102) extending in opposite directions.

Device according to claim 28 or 29,

wherein the salients (101, 102) are mirror images with respect to a plane through a centre of the aperture (82;82'), e.g. a plane parallel to a plane of movement of the receiving part (33).

Device according to any one of the preceding claims,

wherein at least two ports (37-40) of the receiving part (33) are in respective side wall sections on opposite sides of the cavity.

Device according to any one of the preceding claims,

wherein the screening part (35;35') is guided for essentially purely translatory movement, e.g. in an essentially straight line.

Device according to any one of the preceding claims,

wherein the screening part (35;35') is guided for movement along a trajectory in a plane of movement of the receiving part (33).

Device according to any one of the preceding claims,

wherein the screening part (35;35') is guided for a movement maintaining its orientation with respect to the main part. Device according to any one of the preceding claims, wherein the screening part (35;35') is guided for movement by at least two pairs of an edge section and a protruding part (87,88) movable along the edge section.

Device according to claim 35,

wherein the protruding part (87,88) corresponds to at least a section of a projecting rim extending along at least part of the edge section, e.g. a projecting rim forming a flange of the screening part (35;35')-

Device according to claim 35 or 36,

wherein the edge sections are provided by walls (91,92) on either side of the screening part (35;35'), e.g.

walls (91,92) of the main part, and

wherein each edge section adjoins one of a gate and a groove (89,90) in the wall (91,92).

Device according to claim 37,

wherein that one of a gate and a groove (89,90) with which the wall (91,92) is provided is open at at least one end to allow movement of the protruding part (87,88) past the end concerned.

Device for forming a liquid treatment apparatus (1), e.g. according to any one of the preceding claims, the device including :

a receiving part (33) including a cavity arranged to receive a connecting head (10) of a replaceable liquid treat- ment cartridge (3-5) having at least one port (12-15) in liquid communication with an interior of the liquid treatment cartridge (3-5), such that the at least one port(s) (12-15) of the connecting head (10) are in sealed liquid communication with corresponding ports (37-40) of the receiving part (33); and

at least one screening part (35;35'),

wherein the at least one screening part(s) (35;35') presents) external surface sections at least on either side of an aperture (82;82') through which the connecting head (10) of a liquid treatment cartridge (3-5) is insertable into the cavity, and

wherein the surface sections slope inwards towards the aperture (82;82'). Device according to claim 39,

wherein the surface sections slope inwards up to an edge of the aperture (82;82').

Device according to claim 40,

wherein surface sections immediately adjacent to the edge of the aperture (82;82') slope inwards in a direction essentially perpendicular to the edge along at least a majority, e.g. the entirety of its length.

Device according to any one of claims 39-41,

wherein the surface sections are on an opposite side of a wall to correspondingly inclined surface sections of the wall spaced apart from and facing the receiving part (33). Head part for forming a liquid treatment apparatus (1), including at least two interconnected devices (6-8) according to any one of the preceding claims.

Head part according to claim 43,

wherein at least sections of surfaces of the respective screening parts (35;35') of at least two of the interconnected devices (6-8) have a different appearance, e.g. a different colour.

Device for forming a liquid treatment apparatus (1) the device including a head part (2), e.g. a head part according to claim 43 or 44, including :

at least one head part device (6-8), e.g. a device according to any one of claims 1-42,

the head part device including :

a receiving part (33) including a cavity arranged to receive a connecting head (10) of a replaceable liquid treatment cartridge (3-5) having at least one port (12-15) in liquid communication with an interior of the liquid treatment cartridge (3-5), such that the at least one port(s) (12-15) of the connecting head (10) are in sealed liquid communication with corresponding ports (37-40) of the receiving part (33), and

at least one screening part (35;35'), positioned in front of the receiving part (33),

the at least one screening part(s) (35;35') defining an aperture (82;82') through which the connecting head (10) is insertable into the cavity, and the at least one screening part(s) (35;35') being spaced apart from the receiving part (33) in at least one area adjacent the aperture (82;82'); and

an arrangement for mounting the head part (2) with the screening part(s) (35;35') below the receiving part,

wherein the at least one screening part(s) (35;35') includes at least one recess (97) on a side proximal to the receiving part (33) in at least one of the spaced-apart areas.

Device according to claim 45,

wherein at least one of the at least one recesses (97) extends up to one of an edge of the aperture (82;82') and an upstanding ridge (85) forming the edge of the

aperture (82;82').

Device according to claim 45 or 46,

wherein the recess (97) surrounds the aperture (82;82') along a majority of a circumference of the aperture (82;82').

Kit of parts for assembling a device for forming a liquid treatment apparatus (1), e.g. for assembling a device according to any one of claims 1-42 or 45-47, including :

a main part;

a receiving part (33) including a cavity arranged to receive a connecting head (10) of a replaceable liquid treatment cartridge (3-5) having at least one port (12-15) in liquid communication with an interior of the liquid treatment cartridge (3-5), such that the at least one port(s) (12-15) of the connecting head (10) are in sealed liquid communication with corresponding ports (37-40) of the receiving part (33), wherein the receiving part (33) is supported for movement with respect to the main part whilst the connecting head (10) is inserted in the cavity; and

a screening part (35;35') for assembly with the main part in a position with respect to the receiving part (33) enabling the screening part (35;35') to screen off at least part of a space in which the receiving part (33) is arranged to move,

wherein the kit includes an arrangement for guiding the movement of the screening part (35;35'), when assembled, with respect to the main part, at least when the connecting head (10) is inserted in the cavity,

wherein the guiding arrangement includes at least two pairs of an edge section and a protruding part movable along the edge section, and

wherein members of the pairs with which the main part is provided are arranged on opposite side of a space into which the screening part (35;35') is insertable for assembly with the main part.

Kit according to claim 48,

wherein, in an assembled state of the device, the edge sections are provided by walls on either side of the screening part (35;35'), e.g. walls of the main part, and

wherein each edge section adjoins one of a gate and a groove in the wall, and

wherein that one of a gate and a groove with which the wall is provided is open at at least one end to allow movement of the protruding part past the end concerned. Method of assembling a device for forming a liquid treatment apparatus (1), e.g. of assembling a device according to any one of claims 1-42 or 45-47, the method including:

assembling a receiving part (33) with a main part, the receiving part (33) including a cavity arranged to receive a connecting head (10) of a replaceable liquid treatment cartridge (3,4,5) having at least one port (12-15) in liquid communication with an interior of the liquid treatment cartridge (3-5), such that the at least one port(s) (12-15) of the connecting head (10) are in sealed liquid communication with corresponding ports (37-40) of the receiving part (33), wherein, upon assembly with the main part, the receiving part (33) is supported for movement with respect to the main part whilst the connecting head (10) is inserted in the cavity;

providing a screening part (35;35') for assembly with the main part in a position with respect to the receiving part (33) enabling the screening part (35;35') to screen off at least part of a space in which the receiving part (33) is arranged to move,

wherein the screening part (35;35') is assembled with the main part such that the screening part (35;35') is guided for movement with respect to the main part, at least when the connecting head (10) is inserted in the cavity, and

wherein the screening part (35;35') is assembled to the main part subsequent to assembling the receiving part (33) with the main part.

51. Method according to claim 50,

wherein the screening part (35;35') is assembled to the main part by sliding it into the main part. Liquid treatment apparatus, including at least one replaceable liquid treatment cartridge (3-5) and a head part (2) including at least one device (6-8) according to any one of claims 1-42 or 45-47, e.g. a head part (2) according to claim 43 or 44.

Liquid treatment apparatus according to claim 52,

wherein at least two, e.g. three or four, ports (12-15) in liquid communication with an interior of the liquid treatment cartridge (3-5) are provided in the connecting head (10) of at least one of the at least one liquid treatment cartridges (3-5).

Liquid treatment apparatus according to claim 52 or 53,

wherein each liquid treatment cartridge (3-5) has a cartridge axis (11), essentially aligned with the direction of insertion when the connecting head (10) is inserted into the cavity, and

wherein at least one, e.g. all, of the ports (12-15) of the connecting head (10) of at least one of the at least one liquid treatment cartridges (3-5) are provided in respective surface sections (16, 17) facing in directions at an angle to the cartridge axis (11).

Liquid treatment apparatus according to any one of

claims 52-54,

wherein at least one, e.g. all, of the ports (12-15) of the connecting head (10) of at least one of the at least one liquid treatment cartridges (3-5) is provided in an essentially planar respective surface section (16, 17) of the connecting head (10). Liquid treatment apparatus according to any one of

claims 52-55,

wherein each liquid treatment cartridge has a cartridge axis (11) essentially aligned with the direction of insertion when the connecting head (10) is inserted into the cavity, wherein the connecting head (10) of at least one of the at least one liquid treatment cartridges (3-5) and the receiving part (33) of at least one of the at least one head part devices (6-8) are provided with at least one set of alignment parts (22,23,57,58) for axially aligning the cartridge axis (11) with an axis (36) of the receiving part (33) corresponding to a direction of insertion,

wherein each set includes a groove (57,58) and at least one protruding alignment part (22,23) for insertion into the groove (57,58) when the connecting head (10) is inserted into the cavity.

Liquid treatment apparatus according to any one of

claims 52-56,

wherein at least one protruding part (22,23) is provided on the connecting head (10) of at least one of the at least one liquid treatment cartridges (3-5), and

wherein the aperture (82;82') of the screening

part (35;35') of at least one of the at least one head part devices (6-8) has a complementary shape to that of a section of the connecting head (10) including the protruding part(s) (22,23). Liquid treatment apparatus according to any one of

claims 52-57,

wherein at least a section of an edge of the

aperture (82;82') of the screening part (35;35') of at least one of the at least one head part devices (6-8) is arranged to contact the connecting head (10) of at least one of the at least one liquid treatment cartridges (3-5) when inserted into the receiving part (33).