GB2531142A

GB2531142A - Water tap

Info

Publication number: GB2531142A
Application number: GB1515295.2A
Authority: GB
Inventors: Prosser Iain
Original assignee: Greg Rowe Ltd
Current assignee: Greg Rowe Ltd
Priority date: 2014-08-28
Filing date: 2015-08-28
Publication date: 2016-04-13
Anticipated expiration: 2035-08-28
Also published as: GB201415263D0; GB2531142B; GB201515295D0

Abstract

A water tap has a tap body 10 and a rotatable operating arm 400. A valve 200 is rotatable by the operating arm 400 between at least three rotational positions. In a first rotational position, the valve 200 prevents water flowing through the valve 200; in a second rotational position, the valve 200 permits water to flow from a first water inlet through the valve 200; and in a third rotational position, the valve 200 permits water to flow from a second water inlet through the valve 200. The water tap has a cartridge (700, Fig. 10) having a biasing member 800. The operating arm 400 is freely movable between the first and second positions. On movement of the operating arm 400 from the first position to the third position, the arm is biased by the biasing member 800 to the first position.

Description

WATER TAP

Technical Field

The present invention relates to a water tap.

Background

Safety mechanisms for biasing a valve of a hot water tap towards an off position are known in the art. Some safety mechanisms, for example, are configured such that a user is required to apply a continuous force to an operating handle or lever of a tap in order to cause hot water to flow from the tap. When the user stops applying the force, a biasing means coupled to the hot water valve causes the valve to return to an "off position" and to stop the flow of hot water from the tap. This helps to mitigate accidental burning or scalding of the user by the hot water.

Some taps are also configured with more complex "child-proof' mechanisms, which, for example, require a user to both press and rotate an operating handle of a tap in order to cause hot water to flow from the tap. When the user releases the operating handle, the flow of hot water is again quickly stopped.

Often such safety mechanisms are spring loaded, In some systems, for example, a spring is coupled to a water valve to cause the valve to be biased towards an "off position". However, these known mechanisms are complex to manufacture, maintain and repair.

Summary

According to the present invention, there is provided a water tap comprising: a tap body; an operating arm rotatable relative to the tap body; a valve engaged by the operating arm to be rotatable relative to the tap body between at least three rotational positions, wherein: when in a first rotational position, the valve prevents water flowing through the valve; in a second rotational position, the valve permits water to flow from a first water inlet through the valve; and in a third rotational position, the valve permits water to flow from a second water inlet through the valve; and a cartridge having a biasing member retained therein; the arrangement being such that the operating arm is freely movable between the first and second positions; the arrangement further being such that on movement of the operating arm from the first position to the third position, the operating arm is biased by the biasing member of the cartridge to the first position.

In examples of embodiments of the present invention, the cartridge and the biasing member form an integral component which is installable in and removable from the water tap as a whole, separately from the other components of the water tap. This makes installation and servicing of the water tap much more straightforward.

In an embodiment, the biasing member is retained within the cartridge in a pre-tensioned state.

In an embodiment, the biasing member is a coil spring.

In an embodiment, the operating arm comprises a pin and the cartridge comprises an arcuate slot arranged such that the pin of the operating arm moves freely within said arcuate slot when the operating arm is moved between the first position and the second position.

In an embodiment, the operating arm comprises a pin and the cartridge comprises an arcuate slot arranged such that the pin of the operating arm moves within said arcuate slot against the action of the biasing member when the operating arm is moved between the first position and the third position.

In an embodiment, the operating arm comprises a pin, the cartridge comprises a first arcuate slot arranged such that the pin of the operating arm moves freely within the first arcuate slot when the operating arm is moved between the first position and the second position, and the cartridge comprises a second arcuate slot arranged such that the pin of the operating arm moves within the second arcuate slot against the action of the biasing member when the operating arm is moved between the first position and the third position.

In an embodiment, the operating arm comprises a handle which is movable in a radial direction relative to the axis of rotation of the operating arm, the handle of the operating arm being coupled to the pin, the arrangement being such that the pin only engages the arcuate slot to permit the operating arm to move between the first position and the third position when the arm has been moved radially inwards.

In an embodiment, the handle of the operating arm is biased in a radially outward direction towards a position in which the pin is caused to be disengaged from the arcuate slot that permits the operating arm to move between the first position and the third position.

In another embodiment, operating arm comprises a pin and the cartridge comprises an arcuate slot arranged such that the pin of the operating arm moves within said arcuate slot when the operating arm is rotated, and the water tap comprises a drive wheel for acting as an intermediary between the pin and the biasing member, the drive wheel being arranged such that when the operating arm moves from the first position to the second position the pin does not engage the drive wheel and when the operating arm moves from the first position to the third position the pin does engage the drive wheel and acts against the action of the biasing member.

In an embodiment, the arcuate slot comprises a detent, the pin of the operating arm resting in the detent of the arcuate slot when the water tap is not is use.

In an embodiment, the operating arm comprises a handle which is movable in a radial direction relative to the axis of rotation of the operating arm, the handle of the operating arm being coupled to the pin, the arrangement being such that the pin exits the detent to permit the operating arm to move from the first position when the arm has been moved radially inwards.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of example only, which is made with reference to the accompanying drawings.

Brief Description of the Drawings

Figure 1 shows a partially sectioned/phantom perspective view from one side of an example of a water tap body according to an embodiment of the present invention in a first operating configuration; Figure 2 shows a partially sectioned/phantom perspective view from another side of the water tap body of Figure 1 in a second operating configuration; Figure 3 shows a partially sectioned/phantom perspective view from the one side of the water tap body of Figure 1 in a further operating configuration; Figure 4 shows a longitudinal cross-sectional view through a part of the tap body of Figure]; Figure 5 shows an exploded perspective view of examples of first and second tap body parts according to an embodiment of the present invention; Figure 6 shows a longitudinal cross-sectional view of the first and second tap body parts of Figure 5 when assembled; Figure 7 shows a longitudinal cross-sectional view in phantom of the first and second tap body parts of Figure 5 when assembled; Figure 8 shows again the partially sectioned/phantom perspective view from one side of the example of a water tap body of Figure Figure 9 shows a partial cross-sectional view on A-A of Figure 7; Figure 10 shows an exploded perspective view of components of an example of a water tap body according to an embodiment of the present invention; Figure 11 shows a perspective view of a portion of an example of a water tap body according to an embodiment of the present invention to illustrate operation of an operating arm; Figure 12 shows a front perspective view of an example of a cartridge for use in a tap body; Figure 13 shows a rear perspective view of the cartridge of Figure 12; Figure 14 shows an exploded perspective view of components of another example of a water tap body according to an embodiment of the present invention; Figure 15 shows a front perspective view of another example of a cartridge for use in a tap body; and Figure 16 shows a rear perspective view of the cartridge of Figure 15.

Detailed Description

Referring to Figure 1, there is shown a partially sectioned/phantom perspective view of an example of a water tap body 10 according to an embodiment of the present invention. The tap body 10 has a mechanical mixing valve 100 and a mechanical selector valve 200.

The mechanical mixing valve 100 has a first water inlet 1 lOa, a second water inlet I lOb and a water outlet I lOc. The first water inlet 1 lOa is, in one embodiment, in fluid communication with a first tap body inlet (not visible in Figure 1 but generally at the lower end of the tap body 10). In the embodiment depicted in Figure 1, the first tap body inlet is connected to the first water inlet 1 lOa of the mechanical mixing valve 100 via a hollow channel which mns through the tap body 10 from the first tap body inlet to the first water inlet 1 IDa of the mechanical mixing valve 100. The channel is partially shown in cutaway at l2Oa.

In use when the tap body 10 is installed in a work surface or the like, the first tap body inlet is in fluid communication with a first water source. The first water source may be for example a hot water supply, which delivers hot water under pressure to the first tap body inlet via one or more pipes or tubes, such as the pipe 130a.

The second water inlet I lob of the mechanical mixing valve 100 is, in one embodiment, in fluid communication with a second tap body inlet (again not visible in Figure 1 but generally at the lower end of the tap body 10). Similarly to the first tap body inlet, the second tap body inlet is connected to the second water inlet I lOb of the mechanical mixing valve 100 via a hollow channel (not visible in Figure 1, but partially shown in cutaway at 120b of Figure 3) which runs through the tap body 10 from the second tap body inlet to the second water inlet 1 lOb of the mechanical mixing valve 100.

The second tap body inlet 1 lOb may itself be in fluid communication with a second water source. The second water source may be for example a mains cold water supply, which delivers cold water under pressure to the second tap body inlet 11Db via one or more pipes or tubes as described above for the first tap body inlet I ba. The channel 120a that connects the first tap body inlet and the first water inlet 1 ba of the mechanical mixing valve 100 is not connected to the channel 120b that connects the second tap body inlet to the second water inlet IlOb of the mechanical mixing valve other than via the mechanical mixing valve 100, so that water cannot flow directly from one of the inlet channels to the other. This prevents undesired mixing of the water from the two sources.

The water outlet I IDe of the mechanical mixing valve 100 is in fluid communication with a first tap body outlet 140c of the tap body 10 such that water passing out of the water outlet I lOc of the mechanical mixing valve 20 passes to the first tap body outlet 140c, In the embodiment depicted in Figure 1, the water outlet 1 bc is connected to the first tap body outlet 140c via a mixed water outlet channel 120c, which runs through the tap body 10. The mixed water outlet channel 120c is not connected to the channel 120a that connects the first tap body inlet and the first water inlet lb Oa, nor the channel I 20b that connects the second tap body inlet to the second water inlet 11Db, other than via the mechanical mixing valve 100, such that water cannot flow directly from the mixed water outlet channel 120c to the other two channels 120a, t2Ob, This prevents undesired mixing of the water between the three channels 120a, l2Ob, 120c, The mechanical mixing valve 100 is operable to selectively allow water to flow only from the first water inlet I IOa to the water outlet 11 Dc, to allow water to flow only from the second water inlet Ob to the water outlet II Dc, and to allow a mix of water to flow from the first water inlet 1 lOa and the second water inlet 11Db to the water outlet 1 lOc. Such mechanical mixing valves 100 are of particular advantage where the water sources supplying water to the first and second water inlets 1 iDa, 11Db are hot and cold mains water sources. In this case, the mechanical mixing valve 100 is operable to allow the temperature of the water at the water outlet 11 Oc to be controlled by allowing either hot water, cold water, or a mix of hot and cold water, to flow to the water outlet I IDe.

In one embodiment, the mechanical mixing valve 100 is manually operable to allow a selectively variable amount of water to flow through each of the first water inlet I iDa and the second water inlet 11Db into the mechanical mixing valve 100. In other words, the mechanical mixing valve 100 is manually operable to control the flow rate of water from the first water inlet I IDa to the water outlet I bc and the flow rate of water from the second water inlet 11Db to the water outlet 1 iDe, whether the flow is a 3D flow only from the first or second water inlet 1 iDa, 11Db or is a mixed flow.

The mechanical mixing valve mo has a manually operable lever or arm 150.

The arm 150 is operable to control the flow of water from each of the first and second water inlets 1 IDa, I lOb to the water outlet 1 bc of the mechanical mixing valve 100.

In one example, the mechanical mixing valve 100 is coupled to the arm 150 such that S pivoting or rotation of the ann 150 in one plane controls the proportion of water from the first and second water inlets 1 lOa, 1 lOb that is allowed to flow to the water outlet I lOc, and pivoting or rotation of the arm 150 in a second plane perpendicular to the first plane controls the flow rate of the water through the first and second water inlets 1 lOa, 1 lOb thereby controlling the overall flow rate of the water at the water outlet hOc.

Mechanisms for mechanical mixing valves which operate as described above are known as such in the art. One example is a standard 35mm ceramic disk cartridge valve, which includes a fixed disk and a movable disk. In this case, the first and second fluid inlets I IOa, 11Db and the fluid outlet 1 bc are effectively formed as openings within the fixed disk. Movement of the arm 50 causes a corresponding movement of the movable disk, which moves relative to the fixed disk to partially or completely obstmct or completely open the first and second fluid inlets 1 lOa, I lOb and thereby to control the rate of flow of water through each of the two inlets ii Oa, 11Db and to the outlet I bc of the mechanical mixing valve TOO, As mentioned, the tap body 10 also comprises a mechanical selector valve 200, which, in this example, is positioned diametrically opposite the mechanical mixing valve 100. As shown in Figure 2, the mechanical selector valve 200 comprises a first water inlet 210a, a second water inlet 210b and a water outlet 210c. The first water inlet 210a is, in one embodiment, in fluid communication with a third tap body inlet 240a. In the embodiment depicted in Figure 2, the third tap body inlet 240a is connected to the first water inlet 2lOa of the mechanical selector valve 200 via a hollow channel which runs through the tap body 10 from the third tap body inlet 240a to the first water inlet 210a of the mechanical selector valve 200. The channel is partially shown in cutaway at 220a. The channel 220a connecting the third tap body inlet 240a and the first water inlet 2lOa is not connected to any of the other above-described inlet and outlet channels IlDa, IlOb, hOc running through the tap body 10. This prevents undesired mixing of the water in the different channels.

In use when the tap body 10 is installed in a work surface or the like, the third tap body inlet 240a is in fluid communication with a third water source. The third water source may be, for example, a hot or boiling filtered water source, which delivers hot or boiling filtered water under pressure to the third tap body inlet 130 via one or more pipes or tubes, such as the pipe 230a.

The second water inlet 21Db of the mechanical selector valve 200 is, in one embodiment, in fluid communication with a fourth tap body inlet (shown at 240b in Figure 3), Similarly to the third tap body inlet 240a, the fourth tap body inlet 240b is connected to the second water inlet 21Db of the mechanical selector valve 200 via a hollow inlet channel (shown in cutaway at 22Db in Figure 3) which mns through the tap body 10 from the fourth tap body inlet 24Db to the second water inlet 21Db of the mechanical selector valve 200.

The channel 22Db connecting the fourth tap body inlet 24Db and the second water inlet 2 lOb is not connected to any of the other above-described inlet and outlet channels l20a, l2Ob, l2Oc, 220a running through the tap body 10 other than via the mechanical selector valve 200. This prevents undesired mixing of the water in the different channels.

In use when the tap body 10 is installed in a work surface or the like, the fourth tap body inlet 24Db is in fluid communication with a fourth water source. The fourth water source may be, for example, a cold filtered water source, which delivers cold filtered water under pressure to the fourth tap body inlet 135 via one or more pipes or tubes, such as the pipe 23Db.

3D The water outlet 210c of the mechanical selector valve 200 is in fluid communication with a second tap body outlet 240c of the tap body 10 such that water passing out of the water outlet 2lOc of the mechanical selectorvalve 200 passes to the second tap body outlet 240c. In the arrangement depicted in Figure 2, the water outlet 240c of the mechanical selector valve 200 is connected to the second tap body outlet 210c via a channel 220c, which mns through the tap body 10. The outlet channel 220c that connects the water outlet 2 bc of the mechanical selector valve 200 and the second tap body outlet 240c of the tap body 10 is not connected to any of the other above-described inlet and outlet channels 120a, 120b, 120c, 220a, 22Db running through the tap body 10 other than via the mechanical selector valve 200. This prevents undesired mixing of the water in the different channels.

The mechanical selector valve 200 is operable selectively to allow water to flow only from the first water inlet 2tOa to the water outlet 210c of the mechanical selector valve 200, and to allow water to flow only from the second water inlet 21Db to the water outlet 210c of the mechanical selector valve 200. Unlike the mechanical mixing valve 100, therefore, in this example the mechanical selector valve 200 is not operable to allow a mix of water to flow from the first water inlet 2tOa and the second water inlet 210b to the water outlet 210c. Tnstead, the mechanical selector valve 200 allows water to flow from only a single water inlet 210a, 210b to the water outlet 210c at any one time. Such mechanical selector valves 200 are of particular advantage where there is a desire to keep the water supplied to the first water inlet 210a separate from the water supplied to the second water inlet 2 lOb. This may be the case, for example, where the water supplied to the first water inlet 210a is cold filtered water, and the water supplied to the second water inlet 210b is, for example, hot or boiling filtered water or sparkling filtered water say.

In one embodiment, the mechanical selector valve 200, or one or more components thereof is manually operable to move between first, second and third positions, which may be rotary positions of the mechanical selector valve 200. In the first position (see Figure 1 for example), the mechanical selector valve 200 prevents the flow of water through the first and second water inlets 210a, 210b of the mechanical selector valve 200. In the second position (see Figure 2 for example), the mechanical selector valve 200 allows water to flow only from the first water inlet 210a of the mechanical selector valve 200 to the water outlet 21 Dc of the mechanical selector valve ii 200. In the third position (see Figure 3 for example), the mechanical selector valve 200 allows water to flow only from the second water inlet 21 Ob of the mechanical selector valve 200 to the water outlet 21 Oc of the mechanical selector valve 200. As a particular example, the mechanical selector valve 200 may be pivotable or rotatable between the first, second and third positions about an axis.

The mechanical selector valve 200 may be manually operable to move between additional positions, which may cause the valve to carry out additional functions, such as allowing water to flow from a frirther water inlet of the mechanical selector valve 200 to the water outlet 210c of the mechanical selector valve 200.

The "second position" and the "third position" may respectively comprise a range of positions. For example where the mechanical selector valve 200 is rotatable, the "second position" may include all orientations of the mechanical selector valve 200 between the first position and an orientation in which the mechanical selector valve 200 has been rotated by a maximum angle (such as for example 90° or 180°) from the first position. Similarly, the "second position" may include all orientations of the mechanical selector valve 200 between the first position and an orientation in which the mechanical selector valve 200 has been rotated by a maximum angle (such as for example 90° or 180°) in the opposite direction.

In one embodiment, the angle by which the mechanical selector valve 200 has been rotated may control the amount of water that the mechanical selector valve 200 allows to flow to the water outlet 2]Oc of the mechanical selector valve 200. For example, where the "second position" comprises all orientations of the mechanical selector valve 200 between the first position and a 90° clockwise rotation from the first position, a rotation of 90° may cause the mechanical selector valve 200 to allow water to flow from the first water inlet 21Db to the water outlet 21 Oc at a higher rate of flow than when the mechanical selector valve 30 is at say a 45° orientation.

The mechanical selector valve 200 has a manually operable lever or arm 250.

The manually operable arm 250 is coupled to the mechanical selector valve 200 and is operable to cause the mechanical selector valve 200 to allow water to flow only from the first water inlet 21 Oa of the mechanical selector valve 200 to the water outlet 21 Oc of the mechanical selector valve 200, or to allow water to flow only from the second water inlet 21Db of the mechanical selector valve 200 to the water outlet 210c of the mechanical selector valve 200, or to prevent the flow of water from both the first and second water inlets 210a, 21Db of the mechanical selector valve 200 to the water outlet 210c of the mechanical selector valve 200. In particular, the arm 250 is in the orientation as shown in Figure 1, flow of water from both the first and second water inlets 210a, 21Db of the mechanical selector valve 200 to the water outlet 210c of the mechanical selector valve 200 is prevented. When the arm 250 is in the orientation as shown in Figure 2, the mechanical selector valve 200 allows water to flow only from the first water inlet 21 Oa of the mechanical selector valve 200 to the water outlet 21 Dc of the mechanical selector valve 200. When the arm 250 is in the orientation shown in Figure 3, the mechanical selector valve 200 allows water to flow only from the second water inlet 21 Oh of the mechanical selector valve 200 to the water outlet 2 lOc of the mechanical selector valve 200.

As mentioned, the tap body 10 comprises a first tap body outlet 140c, which is in fluid communication with the water outlet 1 iOc of the mechanical mixing valve 100, and a second tap body outlet 240c, which is in fluid communication with the water outlet 210c of the mechanical selector valve 200. In one embodiment, the first and second tap body outlets 140c, 240c may connect to or be formed as part of a spout 20, a lower part of which is shown in Figure 4, In this example, the spout 20 comprises a first water channel 160 and a second water channel 260. The first water channel 160 has an inlet 170 in fluid communication with the water outlet hOc of the mechanical mixing valve 100. The second water channel 260 has an inlet 270 in fluid communication with the water outlet 210c of the mechanical selector valve 200.

In the particular arrangement shown in Figure 4, the first water channel 160 and the second water channel 260 are coaxial channels which are separated by a wall 21, which forms a pipe or tube. Thus, water from the mechanical mixing valve 100 flows in an outer portion of the spout 20, whereas water from the mechanical selector valve flows in an inner portion of the spout 20. In other embodiments, however, the water channels 160, 260 need not be coaxial, and could, for example be formed by two pipes which run next to one another along the spout 20. The spout 20 may be disengageable from the other components from the tap body 10 such that it can be replaced by a different spout also having first and second channels and also to facilitate assembly and installation.

In one embodiment, the tap body 10 is fixable or attachable to a surface, such as a work surface of a kitchen, a surface of a sink, etc. Advantageously, the tap body lOis arranged such that, when the tap body lOis installed on the surface, the mechanical mixing valve too, the mechanical selector valve 200 and the spout 20 including the first and second tap body outlets 140c, 240c are all located on the same side of the surface, which in practice is typically an uppermost surface. By locating the entirety of the mechanical mixing and mechanical selector valves 100, 200 in particular on the same (uppermost) side of the surface as the first and second tap body outlets 140c, 240c, the user has easy access to the valves 100, 200. This simplifies installation of the tap body and is also useful in the event that the valves 200, 300 need to be repaired or maintained or replaced even.

In one embodiment all components of the tap body 10 are mechanical, This has the advantage that no electrical components or electronics or the like need to be installed when the tap body 10 is first installed onto a surface, making installation and maintenance easier, as an electrician is not required to install the tap body tO and no wiring to electrical components or electronics or the like is required.

In one embodiment, the water tap body 10 comprises a first tap body part IDa, and a partially hollow generally cylindrical second tap body part lob which are separable components ofthe water tap body 10, as shown in Figures 5 to 9 in particular.

The first tap body part lOa is configured to receive the mechanical mixing valve 100 at a first hollow generally cylindrical end 180 and to receive the mechanical selector valve at a second, opposed hollow generally cylindrical end 280. The second tap body part Ob is connectable to the first tap body part IDa such that the top surface II a of the first tap body part ba meets with the bottom surface 1 lb of the second tap body part lob. The second tap body part lOb is further connectable to the spout 20 (see e.g. Figure 4). In the example shown, the connection from the second tap body part tOb to the spout 20 is via a hollow generally cylindrical spout inlet bc, which seats in an uppermost part of the second tap body part lob, as will be described in more detail below.

Figure 6 shows a cross-section through exemplary first and second tap body parts lOa, lOb and spout inlet lOc when the first tap body part lOa is connected to the second tap body part lob. The first tap body part lOa comprises first, second, third and fourth tap body inlets, which as discussed above may be connected to respective first, second, third and fourth water sources. Two of these water inlets are shown at 14Db and 240b in Figure 7, with the other water inlets being behind these water inlets 14Db, 240b in the drawing. The first tap body part 1 Oa also comprises first and second mixable water inlet channels and first and second selectable water inlet channels. One of the mixable water inlet channels is shown in phantom at 120b of Figure 7, and one of the selectable water inlet channels is shown in phantom at 22Db of Figure 7, with the other water inlet channels (i.e. the water inlet channels 120a and 220a, which can be seen in Figures 1 and 2 respectively) being behind these water inlet channels t2Db, 22Db in the drawing.

When the mechanical mixing valve 100 is received within the first end 180 of the first tap body part t0a, the first and second water inlets t t0a, t lOb (see e.g. Figure I) of the mechanical mixing valve 100 align with outlets of the first and second mixable water inlet channels such that the first mixable water inlet channel 120c (see e.g. Figure t) routes water from the first tap body inlet to the first water inlet t t0a of the mechanical mixing valve 100 and the second mixable water inlet channel 12Db routes water from the second tap body inlet I 40b to the second water inlet 11Db of the mechanical mixing valve 100. Similarly, when the mechanical selector valve 200 is received within the second end 280 of the first tap body part lOa, the first and second water inlets 210a, 210b (see e.g. Figure 2) of the mechanical selector valve 200 align with outlets of the first and second selectable water inlet channels 220a, 22Db such that the first selectable water inlet channel 220a (see e.g. Figure 2) routes water from the third tap body inlet to the first water inlet 210a of the mechanical selector valve 200 and the second selectable water inlet channel 22Db routes water from the fourth tap body inlet 24Db to the second water inlet 210b of the mechanical selector valve 200.

Referring again to Figure 6, the first tap body part iDa also comprises a portion of the above-described mixed water outlet channel 120c and a portion of the above-described selected water outlet channel 220c. The portion of the mixed water outlet channel 120c is in one example formed of two channels formed at approximately 90° to each other, the first 120c(1) extending from the first end 180 and the second 120c(2) extending from the top surface ii a of the first tap body part 1 Oa, and forming mixed water outlet 120c(3) (see Figure 5). In an embodiment, the first tap body part ba is initially formed as a solid cast or moulded component and these channels 120c(1), 120c(2) are conveniently formed in one example by drilling. These two channels or drill holes 120c(i), 120c(2) meet such that water flows from the first drill hole to the second drill hole. Similarly, the selected water outlet channel 220c is also formed of two drill holes 220c(1), 220c(2), the first 220c0) extending from the second end 280 and the second 220c(2) extending from the top surface 1 la of the first tap body part IOa. The two drill holes 220c(1), 220c(2) meet such that water flows from the first drill hole to the second drill hole.

When the mechanical mixing valve 100 is received within the first end 180 of the first tap body part lOa, the water outlet hOc of the mechanical mixing valve 100 aligns with an inlet of the mixed water outlet channel I I Oc such that water output from the water outlet 1 bc of the mechanical mixing valve 100 flows into the mixed water outlet channel 120c of the first tap body part lOa. Similarly, when the mechanical selector valve 200 is received within the second end 280 of the first tap body part I Oa, the water outlet 210c of the mechanical selector valve 200 aligns with an inlet of the selected water outlet channel 220c such that water output from the water outlet 210c of the mechanical selector valve 200 flows into the selected water outlet channel 220c of the first tap body part iDa.

Figure 8 shows a partially sectioned/phantom perspective view from a side of the water tap body, where the first and second tap body portions ba and lOb and the outlet channels 120cr), 120c(2), 220c(b), 220c(2) can again be seen. The second tap body part lob comprises a generally disk-shape base portion 12b, having a lower surface flb. When connected to the first tap body part IDa, the lower surface 1 lb of the base portion 12b of the second tap body part lOb meets with the upper surface 1 la of the first tap body part lOa, The base portion 12b also comprises an upper surface 13b. Protruding upwardly from the upper surface 13b of the base portion 12b is a generally cylindrical collar portion 14b. The collar portion 14b is shaped to receive an end of the spout inlet lOc, as will be discussed in more detail below.

Protruding from the lower surface I b of the base portion l2b of the second tap body part lOb is a generally cylindrical selected water inlet 15b. When the second tap body part lOb is connected to the first tap body part ba, the selected water inlet lSb is received within an upper portion of the selected water outlet channel 220c(2) of the first tap body part I Oa.

Also formed in the lower surface bib of the second tap body part lOb is an annular recess 16b, When the second tap body part 1Db is connected to the first tap body part ba, the upper surface I Ia of the first tap body bOa and the annular recess lob form an annular channel 120c(4), which forms part of the mixed water outlet channel 120c, as will be described in more detail below.

Referring to Figure 9, which shows a cross-section on A-A of Figure 7 through the second tap body part bOb when viewed from above, the second tap body part lOb also comprises six straight channels 120c(5) to 120c(lO), Two of these straight channels can be seen in Figure 8 at 120c(6) and 120c(7), The six straight channels I 2Oc(5) to I 20c(l 0) form part of the above-described mixed water outlet channel I 20c.

Referring still to Figure 9, the second tap body part lOb also comprises an annular recess 17b (see also Figure 8) formed part way up and intemally of the collar portion I 4b of the second tap body part lob. The annular recess 7b is arranged parallel to and in-line with the first annular recess lob, and the straight channels 120c(5) to 120c(10) extend through the collar portion 14b from the first annular recess 16b to the second annular recess 17b.

S Referring still to Figure 9, the second tap body part I Ob also comprises a channel 220c(4), which extends vertically from the bottom of the selected water inlet lSb to the upper surface 13b of the base portion 12b (see also Figure 8). This channel 220c(4) forms a portion of the above-described selected water outlet channel 220c, In one embodiment, the second tap body part lOb is initially formed as a solid cast or moulded component comprising the base portion i2b, the collar portion t4b, the selected water inlet 15, and the first and second annular recesses lob, I 7b, In this case, the straight channels 120c(5) to 120c(10) are conveniently formed in one example by drilling from the first annular recess lob to the second annular recess 17b. Similarly, the channel 220c(4) of the selected water outlet channel 220c can be formed by drilling from the bottom of the selected water inlet I Sb to the upper surface I 3b of the base portion 12b.

Referring to Figure 8, when the first tap body part t Oa is connected to the second tap body part lob, water flowing from the water outlet 11 Oc of the mechanical mixing valve 100 flows along the mixed water outlet channels 120c(l), 120c(2) of the first tap body part lOa and out of the mixed water outlet 120c(3) of the first tap body part lOa.

The water then flows around the first annular channel t2Oc(4) formed by the first annular recess lob of the second tap body part lob, and up the straight channels I 20c(S) to 120c(l0) to the second annular recess 17b of the second tap body part. Similarly, water flowing from the water outlet 220c of the mechanical selector valve 200 flows along the selected water outlet channels 220c(l), 220c(2) of the first tap body part I Oa and into the selected water outlet channel 220c(4) of the second tap body part lob. 0-rings, such as the 0-rings 30 and 31 depicted in Figure 6, may be fitted between the first tap body part lOa and the second tap body part lOb to prevent water from leaking out of the tap body 10 when it passes from the first tap body part lOa to the second tap body part JOb.

As mentioned above, the second tap body part lOb may, in some embodiments, be connectable to a spout 20 via a spout inlet lOc. As can be seen in Figure 6, the spout inlet lOc is received within the collar portion 14b of the second tap body portion lob, with the connection being sealed by 0-rings 32 and 33. The spout 20 couples to the outside of the spout inlet lOc, as shown in Figure 8, the connection being sealed by one or more further 0-rings. The spout inlet iOc is hollow and comprises a generally cylindrical wall. The spout inlet bc also comprises at least one radial through hole llc, which extends through the cylindrical wall. When the spout inlet lOc is received within the second tap body part lob, water flowing from the straight channels 120c(5) to 120c(IO) and into the second annular recess 17b flows through the through hole 1 ic of the spout inlet bOc, up the spout inlet lOc and into the spout 20. Similarly, water flowing from the selected water outlet channel 220c(4) of the second tap body part lOb also flows up the spout inlet bc and into the spout 20.

As mentioned above in relation to Figure 4, the spout 20 may, in some embodiments, comprise two coaxial channels 160, 260. In this case, the spout inlet bOc may comprise an inner-spout inlet portion 12c. The inner-spout inlet portion 12c is generally cylindrical and comprises an axial channel 13c extending from the bottom of the inner-spout inlet portion]2c to the top of the inner-spout inlet portion 12c. When the spout inlet lOc is connected to the second tap body part lob, the selected water outlet channel 220c(4) of the second tap body part bOb is in fluid communication with the axial channel 13c of the inner-spout inlet portion 12c. The tubular wall 21 which separates the two coaxial channels 60, 260 of the spout 20 (see Figure 4) is connected to the outside of the inner-spout inlet portion 12c. Thus, water flowing from the selected water outlet channel 220c(4) of the second tap body part lOb flows up the axial channel 13c of the inner-spout inlet portion 12c and into the inner channel 260 of the spout 20.

In one embodiment, the inner-spout inlet portion 12c may be formed separately from the rest of the spout inlet lOc. In this case the connection between the inner-spout inlet portion 12c and the rest of the spout inlet iOc may be sealed by an 0-ring, such as the 0-ring 34 (see Figure 6).

By constructing the tap body 10 from (at least) two tap body parts iDa, lob, as described above, the various inlet and outlet channels for routing water from the tap body inlets to the water inlets 120a, 12Db, 220a, 22Db of the valves 100, 200, and for routing water from the water outlets 120c, 220c of the valves 100, 200 to the first and second tap body outlets 140c, 240c can be formed easily and straightforwardly from a number of (straight) drill holes. This makes manufacture of the tap body 10 relatively easy and efficient, and enables the relatively complex and sophisticated arangement of the tap body 10, with its various water channels, and water inlets and outlets, etc., to be achieved. This is in contrast to prior art arrangements, where the whole tap body is typically a single item, which is cast or moulded as a block.

Referring now to Figures 10 to 13, there is shown an exploded perspective view of some components of an exemplary water tap. The water tap comprises a tap body 300. The tap body 300 may be the tap body 10 described above, or an alternative tap body, which comprises different components from those described above. In any event, the water tap of Figures 10 to 13 also comprises an operating arm 400 rotatable relative to the tap body 300, as shown by the curved arrows in Figure 11.

A valve 500 is engaged by the operating arm 400 to be rotatable relative to the tap body 300 between at least three rotational positions. In some arrangements all components of the valve 500 may rotate relative to the tap body 300, and in other arrangements, only some components of the valve 500 may rotate, while other components of the valve 500 remain fixed relative to the tap body 300. In any event, in a first rotational position, the valve 500 prevents water flowing through the valve 500; in a second rotational position, the valve 500 permits water to flow from a first water inlet through the valve 500; and in a third rotational position, the valve 500 permits water to flow from a second water inlet through the valve 500. The valve 500 may, in one embodiment, be a mechanical selector valve, such as the mechanical selector valve 200 of the examples of Figures 1 to 3 described above. In this case, the first water inlet may correspond to the first inlet 210a of Figure 2 and the second inlet may correspond to the second inlet 210b of Figure 2.

The water tap may, in one arrangement comprise a spout, and the valve 500 may be in fluid communication with the spout such that the valve 500 is operable to control the output of water from the spout.

S

In the particular arrangement depicted in Figure 10, the valve 500 is engaged by the operating arm 400 via a toothed stem 600 coupled to the valve 500 such that rotation of the toothed stem 600 causes rotation of the valve 500. The arm 400 comprises a cup-shape engagement end 410, which engages with the toothed stem 600, e.g. via teeth within the engagement end 410, such that rotation of the arm 400 causes rotation of the toothed stem 600 and thus rotation of the valve 500.

The water tap also comprises a cartridge 700 having a biasing member 800 retained therein. In the particular example shown in Figure 10, the cartridge 700 comprises a first cartridge portion 710 and a second cartridge portion 720, which, when assembled, are locked together using a screw 730.

The first cartridge portion 710 comprises an outer cylindrical collar 711, and a front wall 712, which protrudes axially from the cylindrical collar 711. The second cartridge portion 720 comprises an inner cylindrical collar 72 which protrudes axially from a rear wall 722.

When assembled, the cartridge 700 and the biasing member 800 form an integral component which is installable in and removable from the water tap as a whole, separately from the other components of the water tap.

A biasing member, such as the biasing member 800, will typically have a relatively short lifespan due to the tensioning forces applied to the biasing member during operation. Thus, by forming the cartridge 700 and the biasing member 800 as an integral component, the cartridge 700 with the biasing member 800 can be easily replaced when the biasing member 800 reaches the end of its lifespan.

The particular exemplary cartridge 700 of Figure IDis shown in assembled form in Figures 12 and 13. Figure 12 shows a front view of the cartridge 700, and Figure 13 shows a rear view of cartridge 700. As can be seen, the second cartridge portion 720 is received within the outer collar 711 of the first cartridge portion 710. The front wall 712 of the first cartridge portion 710 comprises a through hole 713 which is coaxial with the inner collar 721 of the second cartridge portion 720. When assembled within the water tap, the toothed stem 600 (see Figure 10) passes through the hole 713 in the first cartridge portion 710 and through the inner collar 721 of the second cartridge portion 720 and engages with the engagement end 410 of the operating arm 400.

In the examples shown in Figures 10 to 13, the biasing member 800 is a coil spring which comprises a first leg 810, a second leg 820 and a coil portion 830 (see Figures 12 and 13). The coil portion 830 is received within the inner collar 721 of the second cartridge portion 710. The first leg 810 is movable relative to the cartridge 700, and the second leg 820 is held in a fixed position by a slot 723 of the second cartridge portion 720.

The arrangement of the operating arm 400, the valve 500, the cartridge 700 and the biasing member 800 is such that the operating arm 400 is freely movable between the first and second positions. On movement of the operating arm 400 from the first position to the third position, on the other hand, the operating arm 400 is biased by the biasing member 800 to the first position. Thus, in order to allow water from the second water inlet to flow through the valve 500, a user must apply a constant rotational force to the operating arm 400 to maintain the operating arm 400 in the third position. If the user releases the operating arm 400, the arm 400 is returned to the first position, thereby stopping the flow of water from the second water inlet through the valve 500.

Such an arangement is particularly advantageous where the first water inlet of the valve 500 is coupled to a cold water source and the second water inlet of the valve 500 is coupled to a hot water source. In this case, cold water is permitted to flow through the valve 500 upon rotation of the operating arm 400 from the first position to the second position. As no biasing force is exerted on the operating ann 400 when the operating arm is in the second position, the operating arm 400 will remain in the second position, thereby allowing a continuous flow of cold water through the valve 500, until the operating arm 400 is rotated back to the first position. This may be useful, for example, where a user of the water tap wishes to draw a large volume of cold water from the water tap, for example to fill a sink or bucket. In this case, the user can walk away and leave the tap mnning until the desired amount of water has been drawn.

On the other hand, upon rotation of the operating arm 400 from the first position to the third position, hot water is permitted to flow through the valve 500. However, in this case, because the operating arm 400 is biased by the biasing member 800 towards the first position, the user must apply a continuous force on the operating arm 400 in order to maintain the operating arm 400 in the third position and thereby maintain the flow of hot water through the valve 500. If the user releases the operating arm 400, the arm 400 will return to the first position, thereby quickly stopping the flow of hot water through the valve 500.

In one arrangement, the biasing member 800 is retained within the cartridge 700 in a pre-tensioned state, which is to say that the cartridge 700 applies a tensioning force to the biasing member 800. The biasing member 800 may be tensioned so as to increase the biasing force applied to the operating arm 400 when the operating arm 400 is rotated towards the third position.

In the example arrangement depicted in Figures 10 to 13, the cartridge 700 applies a force to the first leg 810 of the biasing member 800 and thereby holds the first leg 810 in a "tensioned position" in which it is deflected from a "relaxed position". The "relaxed position" is a position in which the first leg 810 would reside, were no force to be applied to the first leg 810. In Figure 12, the first leg 810 is shown in the tensioned position, with the relaxed position being in the anti-clockwise direction. The first leg 810 is held in the tensioned position by an internal retaining means 716 of the cartridge 700, which abuts the left hand side of the first leg 810 when viewed from the perspective shown in Figure 12. The retaining means 716 may be, for example a lip or shelf formed within the cartridge 700.

The cartridge 700 may advantageously allow movement of the first leg 810 in a direction in which it is further deflected from the relaxed position (in Figure 12, the first leg 810 is allowed to move in the clockwise direction), but may prevent movement of the first leg 810 in which deflection from the relaxed position is reduced as compared to the tensioned position (in Figure 12, the first leg 810 is prevented from moving in the anti-clockwise direction beyond the tensioned position by the retaining means 716).

The greater the deflection of the first leg 810 from the relaxed position, the greater the biasing torque applied to a component that is engaged with the biasing member 800.

Thus, by pre-tensioning the biasing member 800, the biasing force applied to the operating arm 400 when it first engages with the biasing member 800 (as will be discussed further below) is greater.

Additionally, by retaining the biasing member 800 in the cartridge 700 in a pre-tensioned state, installation of the biasing member 800 within the water tap is made easier, as the person installing the biasing member 800 is not required to apply any tensioning forces to the biasing member 800 when installing the biasing member 800 into the water tap.

Additionally, by retaining the biasing member 800 in the cartridge 700, the biasing means 800 does not need to be coupled to the valve 500, as is the case in some prior art valve mechanisms. Thus, any conventional rotational valve can be used; there is no requirement for a special valve which comprises means for coupling the valve to the biasing means 800 to be included in the water tap.

In the an-angement shown in Figures 10 to 13, the operating arm 400 comprises a pin 420 which projects generally perpendicularly away from the length of the operating arm 400 (see Figure 10), and the first cartridge portion 710 comprises a first arcuate slot 714 (see Figure 12). The biasing member 800 is held within the cartridge 700 such that the pin 420 moves freely within the first arcuate slot 714 when the operating arm 400 is moved between the first position and the second position. In other words, the biasing member 800 is held within the cartridge 700 such that the pin 420 does not engage the biasing member 800 when the operating arm 400 is moved between the first position and the second position.

When the operating arm 400 is in the first position, the pin 420 is located in the first arcuate slot 714, at the left hand side of the first leg 810. Rotation of the operating arm 400 towards the second position causes the pin 420 to move in the anti-clockwise direction along the first arcuate slot 714 and away from the first leg 810, which is retained in its tensioned position, as discussed above.

The cartridge comprises a second arcuate slot 715 and the biasing member 800 is held within the cartridge 700 such that the pin 420 moves within the second arcuate slot 715 against the action of the biasing member 800 when the operating arm 400 is moved between the first position and the third position.

As mentioned, when the operating arm 400 is in the first position, the pin 420 is located in the first arcuate slot 714, at the left hand side of the first leg 810. Rotation of the operating arm 400 towards the third position causes the pin 420 to move in the clockwise direction along the second arcuate slot 715. As the pin 410 moves along the second arcuate slot 715, the pin 420 displaces the first leg 810 away from the tensioned position, and towards a position whereby the first leg 80 is ifirther displaced from its equilibrium position. Thus, the first leg 810 applies a force to the pin 420, which acts to return the pin 420 to the first position when the operating arm 400 is released.

In one embodiment, the operating arm 400 comprises a handle 430 which is movable in a radial direction relative to the axis of rotation of the operating arm 400, that is parallel to the length of the operating arm 400, as shown by the straight arrow in Figure 11, As shown in Figure 12 for example, the first arcuate slot 714 is radially outward of the second arcuate slot 715. The handle 430 of the operating arm 400 is coupled to the pin 420 such that the pin 420 only engages the second arcuate slot 715 when the handle 430 has been moved radially inwards. Thus, in order to allow water from the second water inlet to flow through the valve 500, a user must first push the handle 430 radially inwards, in order to engage the pin 420 with the second arcuate slot 715. Once the pin 420 is engaged with the second arcuate slot 715, the user is able to rotate the operating arm 400 towards the third position. Such an arrangement forms a useful "child-proofing" mechanism which makes it more difficult to cause water from the second source to flow through the water tap. Such a child-proofing mechanism may S be desirable, for example, where the second water inlet is connected to a hot water source.

Again, if the user releases the operating arm 400 when the ann is in the third position, the arm 400 is returned to the first position under the action of the biasing member 800, thereby stopping the flow of water from the second water inlet through the valve 500. In one embodiment, the handle 430 of the operating arm 400 is biased in a radially outward direction towards a position in which the pin 420 is caused to be disengaged from the second arcuate slot 715. Thus, when the user releases the operating arm 400, and the arm 400 has been returned back to the first position, the pin 420 is disengaged from the second arcuate slot 7 t 5. In this case, in order to permit water to flow from the second water inlet through the valve 500, the user must again push the handle 430 radially inwards before turning the operating arm 400 to the third position.

In the embodiment shown in Figures 10 to 13, the handle 430 is coupled to the pin 420 via a post 440, which is connected to the handle 430 at its upper end, and is connected, to the pin 420 at its lower end (see Figure 4 which shows the operating arm 400 installed on the tap body 10 of Figure 4 and coupled to a mechanical selector valve 200). The post 440 is moveable within a collar 450. Thus, movement of the handle 430 in a radial direction causes movement of post 440 and the pin 420 in the radial direction.

The handle 430 is biased radially outward by a coil compression spring 460, which abuts against collar 450 and an inner surface of the handle 430 (see Figure 4).

When the handle 430 is moved radially inward, therefore, the spring 460 is compressed and a biasing force is applied to the handle 430 in the radially outward direction.

The post 440 comprises a stopper pin 445 which is received within a slot 455 of the collar 450. The stopper pin 445 moves within the slot 455 when the handle 430 is moved in a radial direction. The slot 455 and stopper pin 445 act to restrict the range of radial movement of the handle 430 and therefore the pin 420.

As noted, in one embodiment the first arcuate s'ot 714 is radially outward from the second arcuate slot 715, and the first and second slots 714, 715 are connected by a radial step or slot 717. When the operating ann 400 is installed in the water tap, together with the cartridge 700, the pin 420 is biased by the spring 460 toward the first arcuate slot 714. Thus, when no force is applied to the operating arm 400, the pin 420 resides within the first (outer) arcuate slot 714, and the ann 400 is positioned somewhere between the first position and the second position. In order to cause the arm 400 to rotate to the third position, the arm 400 must first be rotated to the first position (if it is not in that position already) so that the pin 420 is located above the radial step or slot 717 joining the first and second arcuate slots 714, 715. Then the handle 430 must be moved in the radially inward direction, to move the pin 420 into the second (inner) arcuate slot 715. Once the pin 420 is frilly within the second arcuate slot 715, the arm 400 can be moved to the third position, thereby causing water from the second source to flow through the valve 500.

Referring now to Figures 14 to 16, there is shown another example of some components of an exemplary water tap. In the following description and in Figures 14 to 16, components and features that are the same as or similar to the corresponding components and features of the example described above and with particular reference to Figures 10 to 13 have the same reference numeral but increased by 1000. For the sake of brevity, the description of those components and features will not be repeated in its entirety here. It will be understood that the arrangements and alternatives, etc. described above in relation to the example of Figures 0 to 13 are also applicable to the example of Figures 14 to 16.

Again, in broad outline, the operating arm 1400 of Figure 14 is rotatable relative to the tap body 1300 to control the flow of water through valve 1500, with the handle 1430 of the arm 1400 being depressed or moved radially inwards to permit flow of for example hot or boiling water. The principal differences in this example compared to the example described above is that instead of the first leg 810 of the coil spring 800 being received in one of two radially displaced arcuate slots 714,715 in the first cartridge portion 710 and the pin 420 on the operating aim 400 engaging the first leg 810 directly, in this example there is an intermediate drive wheel 1900 between the pin 1420 on the operating arm 1400 aM the biasing member 1800. The drive wheel 1900 receives a first leg 1810 of the coil spring 1800 and also engages with the pin 1420 on the operating arm 1400 when the operating arm 1400 is rotated. An advantage of the example shown in Figures 14 to 16 is that the fitting can be more secure as the pin 1420 on the operating arm 1400 does not directly engage the first leg 1810 of the coil spring 1800.

In the example shown in Figures 14 to 16, the first cartridge portion 1710 has a first arcuate slot 1750 on the front wall 1712. The first arcuate slot 1750 has a detent 1752 at the crest of the arcuate slot 1750. When the operating arm 1400 is not in use the pin 1420 is biased to rest in the detent 1752 by the action of the compression spring 1460. To move the pin 1420, the handle 1430 of the operating arm 1400 is depressed so that the pin 1420 exits the detent 1752. The handle 1430 may then be rotated in either clockwise or anticlockwise direction and the pin 1420 will slide along the first arcuate slot 1750.

The first cartridge portion 1710 has a second arcuate slot 1760 for receiving the first leg 1810 ofthe biasing member 1800. The second arcuate slot 1760 in this example is also arranged on the front wall 1712 of the first cartridge portion 1710, generally opposite the first arcuate slot 1750. The first cartridge portion 1710 has a third arcuate slot 1770 for receiving a projection 1924 of a drive wheel 1900. The third arcuate slot 1770 is arranged in the side wall P40 at a position where the side wall 1740 and the front facing wall 1742 of the first cartridge portion 1710 abut. The side wall 1740 is joined to the front wall 1712. The third arcuate slot 1770 in the example shown is arranged near the first arcuate slot 1750 and away from the second arcuate slot 1760.

The second cartridge portion 1720 shown in Figure 14 has at least one aperture for receiving a second leg 1820 of the biasing member 1800. The second cartridge portion 1720 has an inner cylindrical collar 1721 which protmdes axially away from the rear wall 1722. In this example the inner cylindrical collar 1721 has a smaller radius than the biasing member 1800 and the biasing member 1800 fits over the inner cylindrical collar 1721.

The biasing member 1800 shown in Figure 14 is a coil spring which comprises a first leg 1810, a second leg 1820 and a coil portion 1830 as previously described. The first leg 1810 and second leg 1820 project axially from the coil portion 1830 in a direction parallel to the central longitudinal axis of the coil portion t830. The first leg 1810 projects towards the first cartridge portion IT! 0. The first leg 1810 is received in and projects through an aperture 1910 in the drive wheel 1900. The end of the first leg 1810 is received in the third arcuate slot 1719 in the first cartridge portion 1710. The second leg 1820 of the coil spring 1800 projects away from the first cartridge portion 1710. The second leg 1820 is received in an aperture 1725 in the second cartridge portion 1720. The coil portion 1830 of the coil spring 1800 is arranged around the inner cylindrical collar 1721.

In the example shown the second leg 1820 of the coil spring 800 is received in one of two apertures 1725, 1726. Changing the aperture in which the second leg 1820 of the biasing member 1800 is received allows the tension of the biasing member 1800 to be adjusted. For example, the tension of the biasing member 1800 may degrade over time, or different biasing members 1800 may be manufactured with different inherent spring strengths, and so having a choice of aperture 1725, 1726 in which the second leg t820 is received, the correct or optimum tension can be set or restored.

When the tension of the biasing member 1800 is increased, the radius of the coil portion 1830 tends to decrease. To prevent the biasing member 1800 from damaging the inner cylindrical collar 1721 about which the biasing member 1800 is arranged, a protective member 2000 can be positioned between the biasing member t800 and the inner cylindrical collar 1721. The protective member 2000 is an elongate ring with a diameter less than that of the inner diameter of the biasing member 1800 but greater than the diameter of the inner cylindrical collar 1721. The protective member 2000 is of a similar length to the inner cylindrical collar 1721 to ensure the inner cylindrical collar 1721 is protected from the biasing member 1800, The protective member 2000 can be made of a resilient material such as plastics or rubber for example.

The drive wheel 1900 is generally disk-shape or ring-shape and is arranged between the biasing member 1800 and the first cartridge portion 1710. The drive wheel 1900 has a central aperture 1902 in which a tubular retainer 2100 is received for retaining the drive wheel 1900 in proximity with the biasing member 1800. The drive wheel 1900 has an aperture 1910 through the main ring-like body portion 1904 of the drive wheel 1900 for receiving the first leg 1810 of the biasing member 1800. The aperture 1910 in the example shown is in a lower portion of the drive wheel 1900. The drive wheel 1900 has an annular recess portion 1926 of reduced radius extending around approximately 90°. The annular recess portion 1926 is bounded at one end by a stop 1928 and at the other end by the projecting leg 1924, with a detent or recess 1922 being located between the annular recess portion 1926 and the projecting leg 1924.

When the operating arm 1430 is depressed initially, the pin 1420 of the arm 1400 exits the detent 1752 of the first arcuate slot 1750 of the first cartridge portion but does not enter the recess 1922of the drive wheel 1900. If the operating arm 1400 is turned anticlockwise from a first position to a second position, the pin 1420 can then slide around the annular recess portion 1926 without moving the drive wheel 1900 and thereby without acting against the biasing member 1800. The stop 1928 stops the pin 1420 sliding along the ridge 1926 when the handle 1430 has been fully turned. This is suitable for dispensing cold water, The flow of cold water can be maintained without the user holding the handle 1430 which is useful for a user wishing to obtain large volumes of water.

On the other hand, when the handle 1430 is fully depressed, the recess 1922 receives the pin 1420 of the operating arm 1400. The projecting leg 1924 projects through the third arcuate slot 1770 of the first cartridge portion 1710 and at rest abuts retaining means 17 6 as a result of the torsion generated by the biasing member 1800.

When the pin 1420 is received in the recess 1922, the handle 1430 can be rotated clockwise from a first position to a third position. The pin 1420 of the operating arm 1400 moves against the projecting leg 1924 of the drive wheel 1900. As the pin 1420 moves against the projecting leg 924, the drive wheel 1900 rotates and the first leg 1810 of the coil spring 1800 moves in the second arcuate slot 1760 of the first cartridge portion 1710. The second leg 1820 of the coil spring 1800 is held stationary in the aperture 1725 in the second cartridge portion 1720 and as such the pin 1420 acts against the torsion generated by the coil spring 1800. As for the earlier example this requires the user to hold the handle 1430 in a third position to maintain the flow of water through the valve 1500, This safety feature, whereby when the user releases the handle 1430 the flow of water is ceased, is useful in the operation of a water tap which can provide for example boiling water.

As shown in the example, the retainer 2100 is arranged between the drive wheel 1900 and the first cartridge portion 170. The retainer 2100 is an elongate ring with a diameter less than that of the central aperture 1902 of the drive wheel 1900. The retainer 2100 in the example shown has a lip 2102 at the end proximal to the first cartridge portion 1900, The retainer 2100 is axially aligned with the first cartridge portion. The lip 2102 of the retainer 2100 has a radius larger than that of the hole 1713 in the first cartridge portion 1710 such that the retainer 2100 is held within the cartridge 1700. The retainer 2100 enters both the central aperture 1902 of the drive wheel 1900 and the inner cylindrical collar 1721 so that the drive wheel 1900, biasing member 1800 and the first cartridge portion 1710 are axially aligned. The retainer 2100 increases the stability and therefore the reliability of the cartridge 1700.

The above embodiments are to be understood as illustrative examples of the invention. Further embodiments of the invention are envisaged. For example, one or both of the mechanical mixing valve 100 and mechanical selector valve 200 may provide for inlets and flow control for further inlet water supplies, in addition to the two inlet water supplies described above for each, It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination with one or more features of any other of the embodiments, or any combination of any other of the embodiments.

Furthermore, equivalents and modifications not described above may also be employed without departing from the scope of the invention, which is defined in the accompanying claims.

Claims

CLAIMSI. A water tap comprising: a tap body; an operating arm rotatable relative to the tap body; a valve engaged by the operating arm to be rotatable relative to the tap body between at least three rotational positions, wherein: when in a first rotational position, the valve prevents water flowing through the valve; in a second rotational position, the valve permits water to flow from a first water inlet through the valve; and in a third rotational position, the valve permits water to flow from a second water inlet through the valve; and a cartridge having a biasing member retained therein; the arrangement being such that the operating arm is freely movable between the first and second positions; the arrangement further being such that on movement of the operating arm from the first position to the third position, the operating arm is biased by the biasing member of the cartridge to the first position.
2. A water tap according to claim 1, wherein the biasing member is retained within the cartridge in a pre-tensioned state.
3. A water tap according to claim I or claim 2, wherein the biasing member is a coil spring.
4. A water tap according to any of claims 1 to 3, wherein the operating arm comprises a pin and the cartridge comprises an arcuate slot arranged such that the pin of the operating arm moves freely within said arcuate slot when the operating arm is moved between the first position and the second position.
5. A water tap according to any of claims 1 to 3, wherein the operating arm comprises a pin and the cartridge comprises an arcuate slot arranged such that the pin of the operating arm moves within said arcuate slot against the action of the biasing member when the operating arm is moved between the first position and the third position.
6. A water tap according to any of claims 1 to 3, wherein the operating ann comprises a pin, the cartridge comprises a first arcuate slot arranged such that the pin of the operating ann moves freely within the first arcuate slot when the operating arm is moved between the first position and the second position, and the cartridge comprises a second arcuate slot arranged such that the pin of the operating arm moves within the second arcuate slot against the action of the biasing member when the operating arm is moved between the first position and the third position.
7. A water tap according to claim 5 or claim 6, wherein the operating arm comprises a handle which is movable in a radial direction relative to the axis of rotation of the operating arm, the handle of the operating arm being coupled to the pin, the arrangement being such that the pin only engages the arcuate slot to permit the operating arm to move between the first position and the third position when the arm has been moved radially inwards.
8. A water tap according to claim 7, wherein the handle of the operating arm is biased in a radially outward direction towards a position in which the pin is caused to be disengaged from the arcuate slot that permits the operating arm to move between the first position and the third position.
9. A water tap according to any of claims I to 3, wherein the operating arm comprises a pin and the cartridge comprises an arcuate slot arranged such that the pin of the operating arm moves within said arcuate slot when the operating arm is rotated, and comprising a drive wheel for acting as an intermediary between the pin and the biasing member, the drive wheel being arranged such that when the operating anti moves from the first position to the second position the pin does not engage the drive wheel and when the operating arm moves from the first position to the third position the pin does engage the drive wheel and acts against the action of the biasing member.
10. A water tap according to claim 9, wherein the arcuate slot comprises a detent, the pin of the operating arm resting in the detent of the arcuate slot when the water tap is not is use.
11. A water tap according to claim 9 or claim 0, wherein the operating arm comprises a handle which is movable in a radial direction relative to the axis of rotation of the operating arm, the handle of the operating arm being coupled to the pin, the arrangement being such that the pin exits the detent to permit the operating ann to move from the first position when the arm has been moved radially inwards.