LIQUID OVERFLOW WARNING DEVICE

The present invention relates to a device which provides an instant visual indication or warning when there is a liquid overflow in a liquid container, particularly in toilet cisterns.

It is known that almost all toilet cisterns incorporate an internal overflow pipe in case of situations where the toilet fill valve is faulty. When the toilet fill valve is faulty, it allows a continuous flow of water into the cistern, causing the water level in the cistern to rise to the overflow level, and then continues to flow without the water supply being shut off. The overflowing water is carried in an overflow pipe to either an external point of drainage outside of the building or internally into the toilet pan. External drainage is largely noticeable with the external overflow pipe commonly protruding out of a wall near a door or window. Conversely, internal drainage into the toilet pan largely goes unnoticed, predominantly due to the clear water flowing against a white porcelain toilet pan. The Water Supply (Water Fittings) Regulations 1999 have eliminated the requirement for external overflow pipes in toilets and recognised the reliability of the internal overflow pipe in allowing overflow water to run into the toilet pan as a suitable means of discharging the excess water.

However, water wastage through unnoticed overflow is a major concern to the water industry and environmental agencies, as it is environmentally and economically detrimental, contributing both to water shortages and increased costs to the consumer, respectively.

Water loss through overflow systems is a prominent issue which is regularly documented by water companies and water associations. A faulty toilet can waste up to as much as 400 litres of water per day, and, for the reasons given above, the issue can go undetected for vast lengths of time.

Independent studies, by companies such as Waterwise, indicate that about 8% of all toilets in homes and businesses across the UK are leaking. With an estimated 45 million toilets in use, that equates to approximately 3.6 million toilets which are effectively just wasting water.

One of the current solutions advised by Water Companies is to dry the internal porcelain of the toilet bowl, and place a dry piece of tissue paper on the back of the pan and leave overnight. If the tissue paper is wet in the morning then it should indicate that there is an overflow issue. However, this relies on no one using the toilet during the process, which renders it rather impractical. Additionally, such a system would be very difficult to implement in the commercial sector.

US 2015/0059074 to Davies describes a device which contains a dye tablet that is capable of acting as a visual warning for liquid overflow in toilets. This device works by allowing the water to enter a plastic housing containing the dye tablet, whereby the dye particles become immersed in the water, colouring it.

However, this device requires the use of a permanent fixture in the toilet cistern in the form of the plastic housing, and is not as durable under the damp environments which will be present in toilet cisterns, as it deteriorates, giving result in false diagnoses of mechanical failure. This is because the tablet is designed to dissolve instantly and disperse as quickly as possible, and this occurs in very moist conditions such as toilet cisterns.

The present invention seeks to address the problems associated with existing overflow warning devices and provide a simple, efficient, and cost-effective overflow warning device for liquid containers, particularly toilet cisterns. The present invention is designed to have a longevity period to ensure the fault gets identified quickly, thus drastically reducing the amount of water wasted.

According to a first aspect of the present invention there is provided a device for providing a visual indicator of a liquid level rising above a predetermined level in a liquid container, the device comprising a polymer which is at least partially soluble in water, together with an amount of a dye material.

The device of the present invention produces an instant visual warning by changing the colour of the liquid, such as water, through an overflow system. While a primary application of the device is in liquid overflow detection in a toilet cistern, it can also be used in other scenarios where liquid overflows can be a problem, such as water storage tanks, boiler blow off valve (PRV) or any other kind of pressure release valve, or rainwater harvesting.

According to one embodiment, the device is for use in water-based overflow systems only.

In one embodiment, the device is ideally designed so that it fits directly onto, or into, an overflow pipe in a toilet. In this way, it is able to direct a concentrated steady stream of the dye material directly into the toilet pan, alerting personnel that there is an overflow fault with the toilet. Alternatively, the device may be designed to fit onto syphons and/or cisterns, fitted on or close to the overflow water line.

According to one embodiment of the invention, the device of the present invention may be made partially or entirely from, a unique water-soluble polymer batch, wherein the polymer also comprises an amount of a dye material, such as a fluorescent dye, that is sufficient to provide the visual warning when the water contacts the device and starts to dissolve the polymer, thus providing the visual warning as this coloured water then flows out of the overflow pipe.

The dissolvable polymer may be any suitable polymer which is water-soluble, and which is also preferably non-toxic to humans or animals. Examples of such polymers include, but are not limited to, polymers based on polyvinyl alcohol, which can be acquired from PVOH Polymers Ltd. of Gloucestershire, UK, under the trade names C50, C55, C22.

The dye material used in the device of the invention may be any suitable dye, of any colour, which provides a clear colour contrast from the leaking water, such as a fluorescent dye. Drain tracing dyes are known in the art, and may be obtained from companies such as Tolbest Ltd., Lernco, Bailey Brothers. Examples of such dyes include, but are not limited to, one or more selected from fluoresceine and its derivatives, such as fluoresceine (green) bromafluoresceine (orange). Lood grade dyes can also be used, such as, for example, Red E123, Yellow E102, Purple E151, Blue E133 and Orange El 10.

High levels of the dye material can be incorporated into the polymer, providing a stronger visual indication of a leakage problem. The polymer material may contain up to about 50 wt% of the dye, such as up to about 45, 40, 35, 30, 25, 20, 15, or 10 wt%.

The polymer material used in the device of the invention is also able to expand by up to about 10% in volume, meaning that once it is placed into position, the device will begin to expand and fit firmly in place, such that the device cannot be dislodged.

The polymer material will not deteriorate in a damp atmosphere above the water level, ensuring that the visual alarm is only raised when in contact with water and the polymer starts to dissolve.

The polymer material has a slow rate of dissolution, which gives a long-lasting warning to the overflow. For example, the polymer material typically takes about 2 weeks to dissolve, or being brought into contact with about 6,000 litres of water. This is important, as toilets are often not used for several days, and with the cistern overflowing for a longer period the device will still be able to provide the warning. Existing such warning systems dissolve rapidly, so in the event that the toilets are not used for a number of days, the crucial visual alarm would not be seen as the dye had already dissipated.

This is in contrast to the dye tablet discussed hereinabove, which is designed to dissolve instantly and disperse as quickly as possible, as the dye used in the device of the present invention is locked inside the polymer material, which is designed to withstand moist conditions.

The device is typically located or positioned in an end of an existing overflow pipe, by inserting the device into or onto the pipe. The device is designed so that is securely engaged with the overflow pipe, and may be bespoke designed to fit securely in the overflow pipe of any manufacturer.

In operation, in the event of a liquid overflow situation, water passes over and into the device via a first opening. While passing through the device, the water slowly dissolves outer layers of the water-soluble polymer, releasing the dye material in a substantially uniform manner, lasting for at least about one week (dependent on flow rates of water). The thus coloured water then exits the device via a second opening, from where it travels into the overflow system, such as into the toilet pan. A user can then easily see that the water in the e.g. toilet pan is coloured, and will realise that there is a water leakage problem to be addressed.

A first embodiment of the device of the invention has a first section and a second section, where the circumference of the device around the first section is larger than the circumference of the of the device around the second section. The second section has a more elongated shape for entering the overflow pipe. The first section protrudes proud from the second section, creating a recess thereunder between the first and second sections. Along the respective outer surfaces of the first and second sections are recesses, which are also tailored to fit a specific manufacturer’s overflow pipe.

When installing the device into an overflow pipe, it is the second section which is inserted into the overflow pipe. The size of the device can be made to be bespoke to the sizes of any individual overflow pipes. The first section then fits over the edge of the overflow pipe, with the edge of the pipe fitting securely into the recess between the first section and the second section. If it were necessary to remove the device for any reason, this can also be done easily.

The openings, through which water enters and exits the device, are typically located on an upper surface of the first section, distal from the second section, and at an end of the second section, distal from the first section.

This embodiment of the device can be tailored to fit each manufacturer’s individual overflow pipes, simply by varying the circumference of the device and the respective sections, and the width of the recess.

The first section is typically about 15-25 cm in length. Being located on the outside of the overflow pipe, it acts as an early alarm system to a potential overflow. The device will typically be installed with the cistern water level set below the outer lip of the device. With a fault within the inlet valve, the water level can rise. This is where the water level has risen but has not yet reached the overflow level. Many cisterns have water levels close the top edge of the overflow so the slightest further fault in the inlet valve and the cistern will overflow creating an expense for the customer and a huge additional strain on the precious resource for the water provider. The device of the invention provides an alarm that there is potential for an overflow before the water level has actually reached the top level of the overflow pipe. The water in contact with the outer lip will dissolve the polymer and release the dye into the cistern. When flushing the toilet, the dye will be seen to provide an early alarm that the toilet needs maintaining, before any water has actually been wasted through the overflow pipe. This is beneficial both in terms of costs and water conservation.

When the water levels reach above the top of the first section of the device, the overflowing water then passes through the overflow pipe. It is then in contact with a larger surface area of the polymer on the internal surface of the device, resulting in a greater dye release over a longer period of time to show the dye in the toilet bowl as the water continuously flows.

According to another embodiment of the invention, the device may be designed to be a universal fit into many different sizes of overflow pipes. This is achieved by having a single device which has sections of different sizes within it, enabling it to engage securely with different overflow pipes having different diameters. This device is also manufactured partially or entirely from a water-soluble polymer which has been mixed with a dye material.

The device of this embodiment also has a first section and a second section, with the circumference of the device around the first section being larger than the circumference of the of the device around the second section. The second section has a more elongated shape for entering the overflow pipe. The first section protrudes proud from the second section, creating an overhang and recess between the first section and a second section.

Within this recess is one or more further circular sections, which are arranged concentrically with the circumference of the first section. These one or more further sections each have a narrower circumference than the first section, but a larger circumference than the second section. There may by one, two, three, four, or more, further such sections.

The presence of the one or more further sections results in the formation of one or more further recesses between the respective sections.

It is the presence of these one or more further sections and recesses which permit this device to be used as a universal fit for any overflow pipe, as the different circumferences of the recesses allow the device of this embodiment to engage securely with an overflow pipe, whatever its circumference might be.

In the top of the first section - i.e. the end distal from the second section - there may be a number of openings, through which the water is able to enter in the event of an overflow situation. In one embodiment, there may be a central circular opening, surrounded by a plurality of further openings which may be arranged equidistantly around the circumference of the top of the first section. As many such openings may be used as desired, and in whatever arrangement is preferred.

There is also a second opening in the device, at the end of the second section, distal from the first section. It is through this opening where the water flows when leaving the device and entering the overflow system.

When installing the device of this embodiment into an overflow pipe, the second section is inserted into the overflow pipe, and the first section fits over the edge of the overflow pipe, with the edge of the pipe fitting into whichever recess between the first section and the second section that its diameter corresponds to. As with the embodiment above, in the event of a liquid overflow situation, water passes over the device and enters the overflow system via the one or more of the first openings. While passing through the device, the water slowly dissolves outer layers of the water-soluble polymer, releasing the dye material in a uniform manner lasting for at least one week, thus colouring the water with the fluorescent dye, before the water exits the device via the second opening, from where it travels into the overflow system, such as into the toilet pan.

According to another embodiment of the invention, another device is provided which is designed to be a universal fit into many different sizes of overflow pipes. Again, in a similar manner to the previous embodiment, this is achieved by having a single device which has sections of different sizes within it, enabling it to engage securely with different overflow pipes having different diameters.

This device is also manufactured partially or entirely from a water-soluble polymer which has been mixed with a dye material.

The device of this embodiment only has a first section; it does not possess a second section as the previous embodiment does.

The device of this embodiment has a top and a bottom. Both the top and bottom of the device typically are circular in shape. Overall, the device may be cylindrical in nature, or it may have sides connecting the top and bottom of the device which are sloped, creating a shape and profile where the diameter of the top of the device is larger than that at the bottom.

It is the bottom of the device which engages with an overflow pipe. The bottom of the device has a central opening, which is designed to be the of a diameter to securely fit on an overflow pipe having a certain diameter.

Around the central opening are one or more further circular sections, which are arranged concentrically with the circumference of the bottom of the device. These one or more further sections have sequentially larger diameters, extending out to the edge of the bottom of the device. There may by one, two, three, four, or more, further such sections. The presence of the one or more further sections results in the formation of one or more further recesses between the respective sections. It is the presence of these one or more further sections and recesses which permit this device to be used as a universal fit for any overflow pipe, as the different circumferences or diameters of the recesses allow the device of this embodiment to engage securely with an overflow pipe, whatever its circumference or diameter might be. When installing the device of this embodiment into an overflow pipe, the device is placed onto the overflow pipe, with the edge of the pipe fitting into whichever recess between the first section and the second section that its diameter corresponds to.

In the top of the device - i.e. the end distal from the overflow pipe when the device is installed - there is also a central circular opening, through which the water is able to enter in the event of an overflow situation.

As with the embodiment above, in the event of a liquid overflow situation, water passes over the device and enters the overflow system via the opening in the top of the device. While passing through the device, the water slowly dissolves outer layers of the water-soluble polymer, releasing the dye material in a uniform manner lasting for at least one week, thus colouring the water with the fluorescent dye, before the water exits the device via the opening in the bottom of the device, from where it travels into the overflow system, such as into the toilet pan.

According to another embodiment of the invention, the device may comprise a ‘cradle’ or holder, which is designed to fit onto syphons and/or cisterns, fitted on the overflow water line. The ‘cradle’ element is made from a material which is substantially insoluble in water, and holds, contains or supports a stick or piece of the water-soluble polymer mixed with an amount of the dye material. The cradle may be any shape or design enabling it to fit onto syphons and/or cisterns.

In this embodiment, at least one side of the piece of polymer is exposed for contact with the water. Upon contact with the overflow water, the polymer dissolves gradually from its exposed surface, such as from a lower section of the piece if this is the exposed section. Gravity keeps the stick in contact with the overflow water line as it gradually dissolves.

In this embodiment, the cradle or holder has a void therein which houses a piece of the water-soluble polymer mixed with the dye material. The void may be any shape desired, as the polymer can be shaped to fit any void shape. In one embodiment, the void and polymer piece each have a cylindrical shape. Typically, it is a lower section of the polymer piece which is exposed to contact with the water.

When the lower section contacts the water, the polymer dissolves, releasing the dye into the water. The polymer has a larger density than water, so when the lower section of it is dissolved, the polymer sinks under its own weight, providing further polymer to be dissolved by the water, and further dye release.

The device of this embodiment is designed in order that it is able to hang onto the cistern or clip on to the syphon, so that it holds the polymer piece containing the dye a few millimetres below the line of the overflow level. The device may also be bespoke designed for any individual syphon or cistern, such that it can fit or lock perfectly onto the side of the syphon or cistern.

According to another embodiment of the invention, the dissolvable device of the invention may itself be designed to fit onto syphons and/or cisterns.

In this embodiment, the device comprises a body containing a number of compartments. The body is also made partially or entirely from a water-soluble polymer which has been mixed with a dye material.

There may any number of compartments as desired, such as one, two, three, four, five, six, seven, or more. There is at least one, typically two or more, compartments which are able to contain one or more capsules, added via openings in the top of the device. There may also be at least one further, separate compartment, of whatever shape and dimension desired, into which an amount of the water-soluble polymer mixed with dye material can be added. This polymer and dye mixture may be in a granular or powder form. If desired, an amount of foaming soap powder and/or compressed powdered drain dye may be added to the water- soluble polymer mixed with dye material. The presence of the foaming soap powder would create a foaming effect in the WC pan, thus making the presence of a leak even more obvious.

In one aspect, the device of this embodiment may have an elongated shape, and contain three compartments, two compartments to contain capsules, and one compartment to contain an amount of the water-soluble polymer mixed with dye material. This compartment is typically larger than the capsule compartments. Typically, the capsule compartments are located at either end of the elongated device, with the compartment containing the water- soluble polymer mixed with dye material being located between the capsule compartments.

The underside of the device is typically not flat. Each of the capsule compartments typically has an end which has a hemispherical shape which extends proud from the device. The underside of the compartment containing the water-soluble polymer mixed with dye material may be flat, or it may have one or more nodules thereon. These nodules may have any shape desired, including a hemisphere, but they are smaller than the hemispheres which form part of the capsule compartments.

The capsules are typically spherical in shape, and comprise two halves which can be separated from each other. They are also made from the water-soluble polymer mixed with dye material. The inside of the capsules is substantially hollow when they are empty. However, typically contained with each capsule is an amount of a material. This may be a further amount of the water-soluble polymer mixed with dye material, or it may be an amount of compressed powdered drain dye, or a combination of both. The amount of the material may be in the appropriate shape to fit in the capsule; for example, when the capsule is spherical, the material may be in the form of a ball, for example one which is about 10-20 mm, or 15 mm, in diameter.

There may be any number of capsules as desired in the device, depending upon their size, such as one, two, three, four, five, six, seven, or more.

The device of this embodiment may also be provided with a lid to close it, which will go over the top of the compartments.

This device works by the hemispheres which form part of the capsule compartments providing a first point of contact with the water line during mechanical failure of the WC components causing the WC to leak via the internal overflow into the WC pan. The water- soluble polymer then starts to dissolve, releasing dye into the cistern and gradually exposes the capsules in their compartments.

Eventually the capsules themselves start to dissolve and fall into the cistern, where they will expose the dye ‘ball’ within the capsule, releasing additional amounts of dye into the cistern and prolonging leak detection. This process will continue until all of the capsules are released into the bottom of the cistern.

The same process applies to the nodules on the underside of the compartment containing the granular or powder water-soluble polymer mixed with dye material. However, in this instance, once the underside of the compartment has dissolved sufficiently, it releases the granular water-soluble polymer mixed with dye material, as well as the foaming soap powder and/or compressed powdered drain dye if present, adding a further increased concentrate of dye to the cistern water. This embodiment of the device may be attached to the toilet by an attachment apparatus. By way of non-limiting example, the device may be held in a holder made from a water insoluble polymer, such as polypropylene, which can extend around the device. The holder also contains a section which can adjustably engage with a hanger. The holder is typically able to be adjusted up and down on the hanger, so the appropriate height for the device can be achieved for any given cistern and water line.

The device of the invention has a number of technical advantages over existing overflow warning systems:

The device of the invention is able to fit directly onto, or into, an overflow pipe in a toilet, irrespective of the size of the pipe of the manufacturer;

The device of the first embodiment of the invention uses a dissolvable polymer that leaves behind no waste once it is completely spent, as opposed to leaving behind a housing, such as a plastic container housing as in previous devices;

The primary design for the device of the first embodiment of the fits directly into the overflow pipe and therefore delivers a high concentrated level of fluorescent dye into the WC pan over a number of weeks, rather than ‘clipping’ onto the outside of the overflow pipe - also releasing its contents instantly when in contact with water to dye the whole content of the cistern or vessel;

The polymer mix allows high levels of concentrated dye to be impregnated into the solid formed device of the invention, giving it a greater surface area to release the dye during the dissolving process, as opposed to a small tablet form within a container; and

The polymer can withstand damp environments which will be present in toilet cisterns, as opposed to a dye tablet which deteriorates in similar conditions - which could then result in false diagnoses of a mechanical failure.

The device of the invention is a low cost, affordable solution which has the potential to be fitted into any toilet worldwide.

In a second aspect of the present invention, there is provided a method of providing a visual indicator of a liquid level rising above a predetermined level in a liquid container, the method comprising using a device comprising a polymer which is at least partially soluble in water, together with an amount of a dye material. The polymer and dye material are as described herein above.

The method may involve inserting the device directly onto, or into, an overflow pipe in a toilet.

In a second aspect of the present invention, there is provided a method of manufacturing a device as described herein above, the method comprising mixing a polymer which is at least partially soluble in water with an amount of a dye material. The device may be made by techniques such as injection molding or 3D printing.

The polymer and dye material are as described herein above.

The invention will now be described further by way of example with reference to the following examples and figures which are intended to be illustrative only and in no way limiting upon the scope of the invention. In Figures 1-6, the features of this embodiment and variants thereof are as follows:

Figures 1(a)- 1(f) show different perspectives of a version of the invention tailored to fit a specific overflow pipe.

Figures 2(a)-(c) and 3(a)-(c) each show how the device of the invention fits into a specific manufacturer’s overflow pipe.

Figures 4(a)-4(h) show a version of the invention designed to be a universal fit into many different sizes of overflow pipes.

Figures 5(a)-5(i) shows an embodiment of the invention designed to fit onto syphons and/or cisterns.

Figure 6 shows a number of representations of a dissolvable polymer dye stick which can be inserted into the embodiment of Figure 5.

Figures 7(a)-7(e) show another embodiment of the invention designed to be a universal fit into many different sizes of overflow pipes.

Figures 8(a)-8(c) show another embodiment of the invention designed to fit onto syphons and/or cisterns.

Figure 9 shows a number of perspectives of the embodiment in Figures 8(a) and 8(b) together with an attachment device. Figure 10 shows an exploded view of the embodiment in Figures 8(a), 8(b) and 9, with all of the elements present.

For convenience only, the embodiments of the invention as shown in the Figures will be described in relation to the liquid being water and the liquid container being a toilet cistern.

Figures 1(a) and 1(b) show different representations and perspectives of a device A according to the invention. The device A is manufactured from a water-soluble polymer which has been mixed with a fluorescent dye. The device A can be located or positioned in the existing overflow pipe for the toilet, by inserting the device A into the pipe. The device A has a first section (2) and a second section (3), where the circumference of the device A around the first section (2) is larger than the circumference of the of the device A around the second section (3). The first section (2) protrudes proud from the second section (3), creating an overhang, which forms a recess (7) thereunder between the first and second sections (2,3). Along the respective outer surfaces of the first and second sections (2,3) are recesses (4,5), which are also tailored to fit a specific manufacturer’s overflow pipe. Alternatively, in other embodiments, the recesses (4,5) may not be required at all. Further, the circumferences of the device A can be varied during manufacture in order that the device A can fir any diameters of overflow pipes.

When installing the device A into an overflow pipe, the second section (3) fits securely into the overflow pipe. The size of the device A can be made to be bespoke to the sizes of any individual overflow pipes. The first section (2) fits over the edge of the overflow pipe, with the edge of the pipe fitting into the recess (7) between the first section (2) and the second section

(3).

In the event of a liquid overflow situation, water passes over the device A and enters the overflow system via a first opening (1). While passing through the device A, the water dissolves an amount of the water-soluble polymer and becomes coloured by the fluorescent dye, before exiting the device A via a second opening (6), from where it travels into the overflow system, such as into the toilet pan.

Figures 1(c) and 1(d) each show perspectives of the device A from above and below. In Figure 1(c), only the first section (2) with the first opening (1) can be seen. In Figure 1(d), the bottom of the second section (3) can be seen, along with the second opening (6), as well as the recess (7) between the first and second sections (2,3). Figure 1(e) shows a side perspective of the device A, with the first and second sections (2,3) visible, with a centreline A-A shown. Figure 1(f) shows a cross-sectional view of the same perspective of the device A, with the recess (7) clearly visible between the first and second sections (2,3).

Figures 2(a)-(c) and 3(a)-(c) each show a device A according to the invention when fitted into and onto an overflow pipe (8).

In Figure 2(a), the device A is shown fully inserted into and onto an overflow pipe (8). Only the first section (2) with the first opening (1) can be seen, along with the recess (4) in the first section (2).

Figure 2(b) shows a cross-sectional view of the device A along the A-A line from Figure 2(c), with the device fully inserted into and onto an overflow pipe (8). It can be seen that the outer edges of the overflow pipe (8) securely engage with the device A via the recess (7).

Again, in the event of a liquid overflow situation, water passes over the device A and enters the overflow system via a first opening (1). While passing through the device A, the water comes into contact with the internal surface (9) of the device A, where the water dissolves an amount of the water-soluble polymer and becomes coloured by the fluorescent dye, before exiting the device A via a second opening (6), from where it travels into the overflow pipe system in the direction (10), such as into the toilet pan.

Figure 2(c) shows a side view of the device A fully inserted into and onto an overflow pipe (8).

Figures 3(a)-(c) show the same perspectives of the device A and overflow pipe (8) as are shown in Figures 2(a)-(c), but showing the device A as it is being inserted into and onto the overflow pipe (8), and prior to the engagement of the overflow pipe (8) with the device A via the recess (7). Figure 3(b) shows a cross-sectional view of the device A along the B-B line from Figure 3(c).

Figures 4(a)-4(h) show another embodiment of the invention from a number of different perspectives. This embodiment (denoted as Device B) is designed to be a universal fit into many different sizes of overflow pipes. The device B is also manufactured from a water- soluble polymer which has been mixed with a fluorescent dye. Figures 4(a) and 4(b) show views of device B from above. The device B has a first section (20) and a second section (22), the circumference of the device B around the first section (20) being larger than the circumference of the of the device B around the second section (22), and the second section (22) having a more elongated shape. The first section (20) protrudes proud from the second section (22), creating an overhang.

In the top of the first section (20) - i.e. the end distal from the second section (22) - there are a number of openings (24), through which the water is able to enter in the event of an overflow situation. In this embodiment, there is a central circular opening (25), surrounded by four further openings arranged equidistantly around the circumference of the top of the first section (20).

Figures 4(c) and 4(d) show views of device B from below. The underside of the first section (20) can be seen in these views, where there is a third section (26) arranged concentrically with the circumference of the first section (20), but with a narrower circumference. The third section (26) also has a larger circumference than the second section (22).

Between the edges of the first section (20) and the third section (26) is a first recess (28), and between the edge of the third section (26) and the second section (22) is a second recess (30). While two such concentric circular sections are shown in this embodiment, more such sections could be employed. It is the presence of these circles which permit this device B to be used as a universal fit for any overflow pipe, as the different circumferences of the recesses allow this device B to fit the different circumferences of overflow pipes.

Figures 4(c) and 4(d) also show a second opening (32) in device B, at the end of the second section (22). It is via this opening (32) where the water flows when leaving the device B and entering the overflow system.

Figures 4(e) and 4(f) each show perspectives of the device B from above and below. In Figure 4(e), only the first section (20) with the first openings (24) can be seen. In Figure 4(f), the bottom of the second section (22) can be seen, along with the second opening (32).

Figure 4(g) shows a side perspective of the device B, with the first and second sections (20,22) visible, with a centreline A-A shown. Figure 4(h) shows a cross-sectional view of the same perspective of the device A, with the recesses (28,30) clearly visible in the overhang between the first and second sections (20,22), as well as the central opening at the top of the first section (20) and the opening at the bottom of the second section (22).

When installing the device B into an overflow pipe, the second section (22) fits securely into the overflow pipe. The first section (20) fits over the edge of the overflow pipe, with the edge of the pipe fitting into whichever recess (28,30) between the first section (2) and the second section (3) that its diameter corresponds to.

As with the embodiment in Figure 1, in the event of a liquid overflow situation, water passes over the device B and enters the overflow system via the one or more of the first openings (24). While passing through the device B in the direction (33) towards opening (32), the water slowly dissolves outer layers of the water-soluble polymer, releasing the dye material in a uniform manner lasting for at least one week, thus colouring the water with the fluorescent dye, before the water exits the device B via the second opening (32), from where it travels into the overflow system, such as into the toilet pan.

Figures 5(a)-5(i) show different perspectives of another embodiment of the device of the invention. This embodiment (denoted as Device C) is designed to fit onto syphons and/or cisterns it may be any suitable design for this purpose, and Figure 5 merely depicts one of the them. It is made from a material which is substantially insoluble in water.

Figures 5(a) and 5(b) show perspectives of the device from above and below, in which a dissolvable polymer dye stick (34) - representations of which are shown in Figure 6 - loaded into a void (36) in the top section of the device, via top opening (38). The bottom of the polymer dye stick (34) is exposed at the bottom of the void (36) in order that it can come into contact with the water when its level rises. While the shape of the polymer dye stick (34) may be any shape convenient, it is depicted as a cylindrical shape here.

When the water level rises, it comes into contact with the bottom of the polymer dye stick (34), and begins to dissolve it slowly, releasing the dye into the water. Gravity keeps the stick in contact with the overflow water line as it gradually dissolves. The polymer has a larger density than water, so when the lower section of it is dissolved, the polymer sinks under its own weight, providing further polymer to be dissolved by the water, and further dye release.

The device C has a first protrusion (42) and a second protrusion (44), which enable the device to be fitted securely on to the syphon or cistern, so that it holds the polymer piece containing the dye a few millimetres below the line of the overflow level. The cross-shaped opening (46) shown in Figure 5(i) is an opening which enables the device to fit a specific manufacturer’s syphon. This cross shape enables the device to fit or friction grip on to a peg which is on the syphon. However, it will be appreciated that this opening may have different shapes depending upon the design of the syphon it is needed to fit on.

In the event of a liquid overflow situation, water passes over the device C and comes into contact with the top of the dissolvable polymer dye stick (34). The water slowly dissolves outer layers of the water-soluble polymer, releasing the dye material in a uniform manner lasting for at least one week, thus colouring the water with the fluorescent dye, before the water exits the device C via the second opening (40), from where it enters the overflow system via a first opening (38), from where it travels into the overflow pipe system in the direction (10), such as into the toilet pan. This is depicted in Figure 5(c), which shows a cross-sectional side view of the device as shown in Figure 5(d).

Figures 5(e) and 5(f) show views of device C from both above and below. The top of protrusion (42) and opening (38) to the void (36) can be seen in Figure 5(e), while the underside of protrusion (44) and the other end of the void (36) can be seen in Figure 5(f).

Figures 5(g) and 5(h) depict alternate side perspectives of the device C.

Figures 7(a)-7(e) show another embodiment of the invention from a number of different perspectives. This embodiment (denoted as Device D) is also designed to be a universal fit into many different sizes of overflow pipes. The device D is also manufactured from a water-soluble polymer which has been mixed with a fluorescent dye.

Figure 7(a) shows views of device D from above, the side, below, and an isometric view. The device D has a top or upper surface (46), a side (48), and a lower surface or bottom (50).

In the top (46) of the device - i.e. the end distal from the overflow pipe when the device D is installed - there is a central opening (52), through which the water is able to enter in the event of an overflow situation.

Within the device D, visible from the bottom (50) of the device, is the other end of the central opening (52), through which the water flows when leaving the device D and entering the overflow system. There are a number of sections (54) which are arranged concentrically with the circumference of the opening (52), but with sequentially increasing diameters and circumferences extending out to the side (48) of the device D.

Between the sections (54) are a number of concentric recesses (56). It is the presence of these recesses which permit this device D to be used as a universal fit for any overflow pipe, as the different circumferences and diameters of the recesses allow this device D to fit the different circumferences and diameters of different overflow pipes.

Figures 7(b) and 7(c) show the different sections (54) within the device D. in this embodiment, there are three such sections, each with a decreasing diameter from top to bottom in the Figure. It can be seen how these sections fit together within each other within the device

D.

Figure 7(b) shows a side-on view of these sections, while Figure 7(c) shows an exploded isometric view of these sections, including some hidden lines.

Figures 7(d) and 7(e) show the device D when it is engaged with an overflow pipe (64). In Figure 7(d), for example, the device D is engaged with an overflow pipe with a diameter of 28mm, with the overflow pipe (64) placed into the opening (52) at the bottom of the device D. Three different perspectives of this are show, from below, from the side, and from above. As this pipe is only 28mm in diameter, it fits securely in one of the narrower diameter recesses within the device D.

In Figure 7(e), the same perspectives are shown, but this time the device D is engaged with a larger overflow pipe (66) with a diameter of 39mm. This overflow pipe (66) is also inserted into the bottom of the device D, but engages securely with a different recess than the narrower 28mm pipe (64).

In the event of a liquid overflow situation, water passes over the device D and enters the overflow system via the openings (52). While passing through the central opening (52) in the device D, the water slowly dissolves outer layers of the water-soluble polymer, releasing the dye material in a uniform manner lasting for at least one week, thus colouring the water with the fluorescent dye, before the water exits the device D via the other end of the central opening (52) in the bottom of the device, from where it travels into the overflow system, such as into the toilet pan. Figures 8(a)-8(c) show the dissolvable device of the invention designed to fit onto syphons and/or cisterns.

Figure 8(a) shows the device (66) with its lid (68) thereon, which are elongate in shape. The device (66) and its lid (68) are each made partially or entirely from a water-soluble polymer which has been mixed with a dye material. At each end of the device (66) are capsule compartments (70) for containing one or more capsules, added via openings in the top of the device (openings hidden by the lid). Between the capsule compartments (70) is a central compartment (72), which contains an amount of the water-soluble polymer mixed with dye material, which may be in a granular or powder form, and optionally an amount of foaming soap powder and/or compressed powdered drain dye may be added to the water-soluble polymer mixed with dye material.

The capsule compartments (70) have hemispherical-shaped ends (74), which come into contact with the water first.

Figure 8(b) shows an exploded view of the capsule (76). The capsule is in two halves (76a, 76b), which can be separated from each other. Within the capsule (76) is a ball (78) of an amount of the water-soluble polymer mixed with dye material, or it may be an amount of compressed powdered drain dye, or a combination of both.

Figure 8(c) shows the device (66) with its lid (68) off. This shows the openings (80) of the capsule compartments (70), into which the capsules (76) are inserted. In this embodiment, three capsules (76) are placed into each of the capsule compartments (70). The spherical shape of the capsules (76) means that the bottom capsule (76) in each capsule compartment (70) sits in the hemispherical-shaped ends (74).

The central compartment (72) has its opening, into which the water-soluble polymer mixed with dye material, optionally with foaming soap powder and/or compressed powdered drain dye, is added.

In use, the hemispherical-shaped ends (74) provide a first point of contact with the water line during any mechanical failure of the WC components causing the WC to leak via the internal overflow into the WC pan. The water-soluble polymer comprising the device then starts to dissolve, releasing dye into the cistern and gradually exposes the capsules (76) in their compartments (70). Eventually the capsules (76) themselves start to dissolve and fall into the cistern, where they will expose the ball (78) within the capsules (76), releasing additional amounts of dye into the cistern and prolonging leak detection. This process will continue until all of the capsules (76) are released into the bottom of the cistern.

The same process applies to nodules (not shown) on the underside of the central compartment (72). However, in this instance, once the underside of the compartment has dissolved sufficiently, it releases the granular water-soluble polymer mixed with dye material, as well as the foaming soap powder and/or compressed powdered drain dye if present, adding a further increased concentrate of dye to the cistern water.

Figure 9 shows a number of different perspectives of the device (66) in Figures 8(a)- 8(c) together with its holder (80) and an adjustable hanger (82).

The device (66) is placed securely in the holder (80). At one part of the holder (80) is a connector (84), which enables the hanger (82) to engage with the holder (80). The hanger (82) is inserted into the connector (84), and remains in place due to the protrusions or teeth (86) on the hanger (82). The device (66) and holder (80) can be adjustably moved up and down the hanger (82) to achieve an appropriate height for the device (66) relative to the water line, in each position being able to remains in place due to the protrusions or teeth (86) on the hanger (82). The hanger (82) has a hook element (88) which allows it to engage with and hold on to a surface to suspend the device (66) in position.

The nodules (90) on the underside of the central compartment (72) can be seen in Figure 9. These are also hemispherical in shape, but are smaller than the hemispherical-shaped ends (74) which form part of the capsule compartments (70).

Figure 10 shows an exploded view of the embodiment in Figures 8(a)-8(c) and 9, showing all of the elements present.

It is of course to be understood that the present invention is not intended to be restricted to the foregoing examples which are described by way of example only.