WO2011137490A1

WO2011137490A1 - Sanitizing system

Info

Publication number: WO2011137490A1
Application number: PCT/AU2011/000517
Authority: WO
Inventors: Brian Gay
Original assignee: Quench Solutions Pty Ltd
Priority date: 2010-05-07
Filing date: 2011-05-06
Publication date: 2011-11-10

Abstract

The present invention relates to a sanitising system for sanitising plumbing or pipework and associated fittings that are employed in certain recirculation systems such as fill and drain spa baths or whirlpool tubs and recirculating showers. In one particular aspect the invention provides a recirculation system including pipework having an inlet arranged to receive liquid for recirculation and an outlet to which the liquid is delivered for discharge, the system further including a valve arrangement for closing the inlet and the outlet, a sanitizer inlet for introducing sanitizer into the pipework and a pumping arrangement to pump sanitizer within the pipework.

Description

SANITIZING SYSTEM

FIELD OF THE INVENTION

The present invention relates to a sanitising system for sanitising plumbing or pipework and associated fittings that are employed in certain recirculation systems such as fill and drain spa baths or whirlpool tubs and recirculating showers.

BACKGROUND OF THE INVENTION

Spa baths or whirlpool tubs (hereinafter "whirlpool tubs") and recirculating showers operate by recirculation of water that has been dispensed into the tub or shower. Whirlpool tubs include a large reservoir for containing a body of water within which a person can bathe, and a plurality of nozzles or jets (hereinafter "jets") that open into the reservoir and through which recirculated water is injected under pressure generally for therapeutic or relaxation purposes. Water is drawn out of the reservoir through a suction outlet by a recirculating pressure pump for recirculation back to the jets via suitable plumbing or pipework (hereinafter "pipework").

Recirculating showers typically collect water as run-off from the base of the shower and direct the water to a reservoir which is in communication with a pump for pumping the water back to the shower head. Applicant's co-pending US application 12/310,889, published under US 2009/0300839, discloses one form of recirculation shower system which employs a reservoir in the shower base and describes various prior art systems.

Hygiene is extremely important in relation to whirlpool tubs and recirculating showers, regardless of whether the tub or shower is a commercial installation, such as in hotels and spa treatment facilities, or in a residential installation. Because whirlpool tubs and recirculating showers recirculate water that has been in contact with the body of the bather, oils, salts, fats, skin tissue and body fluids from the bather are also circulated through the recirculation system, i.e. through the pipework, jets, pump etc. Thus, the recirculation system can become soiled by residue build up on surfaces of the system which, for hygiene purposes, would be preferable to remove after each use of the whirlpool tub or recirculating shower. However, access to the components of the recirculation system is usually difficult and as a consequence the components are often very difficult to clean. Also, the recirculation system can form an excellent breeding environment for bacteria and potential pathogens, particularly if water can collect in the system and become stagnant. This is despite that fill and drain whirlpool tubs and recirculating showers are drained after each use, as draining on its own does not thoroughly clean the components of the recirculation system, particularly residue or build up on surfaces of the components. Accordingly, the recirculation system can present significant hygiene difficulties. Moreover, given that whirlpool tubs and recirculating showers in commercial operations are used by many different people, their hygienic maintenance is essential. US Patent 5587053 in the name of Sanijet Corp provides a detailed summary of papers detailing the dangers associated with unclean pipework in whirlpool tubs.

Currently there are several methods employed for sanitizing the recirculation system of bathing and showering apparatus such as whirlpool tubs and recirculating showers. One method employed for whirlpool tubs involves re-filling the tub with fresh water, adding sanitizer and operating the tub for a predetermined period of time which is dependant on the level of sanitizer contact which is required for proper sanitization of the components of the recirculation system. The contact time of currently used sanitizers is typically between 1 to 5 minutes. After that time, the tub is emptied. The tub is then re-filled again with fresh water and is operated again in order to flush the sanitizer completely from the tub and the components of the recirculation system before the tub is considered hygienically ready for the next use. Flushing of the sanitizer is also required because if the sanitizer is not fully flushed away, it will cause spume or foam to be produced when the tub is next used.

The above method is both time consuming and extremely wasteful of water. Hotels for example, invest significant time and money in cleaning whirlpool tubs in hotel complexes this way. For example many whirlpool tubs hold approximately 500 litres of water and for such tubs, at least 350 litres of water is required to re-fill the tub to the required level (just above the level of the jets of the tub) for sanitizing. Thus, at least 700 liters of water is used for the sanitizing process. Clearly this is very wasteful.

A further drawback with the above method relates to the amount of sanitizer that is required. Because the sanitizer is mixed with the water in the reservoir and is thus significantly diluted, a greater amount of sanitizer is required than the amount that would be sufficient to sanitize just the internal surfaces of the components of the recirculation system. This adds to the cost of the sanitizing procedure.

The type of sanitizer is also important in the present methods, because some sanitizers can tarnish or otherwise affect the fittings of whirlpool tubs, so excluding their use. However, these sanitizers can otherwise provide good sanitizing results so that their use, if possible would be preferred.

A still further drawback relates to the labour intensity of the sanitizing process, particularly in hotels and other commercial operations, in which high levels of cleanliness are usually required to be achieved in the shortest possible time. This labour intensity typically occurs because the cleaner must observe the whirlpool tub while it is filling and is required to add the sanitizer and operate the tub for the duration of the sanitizing cycle. Filling alone can take 10 to 15 minutes and in the above method, filling is required twice.

Another method used to clean the recirculation system of whirlpool tubs is to flush fresh water and sanitizer through the system after the tub has been drained of water. This method also uses substantial amounts of water and sanitizer because the water and sanitizer mixture discharges through the jets of the system. This method can also deliver inconsistent results, because it employs mains water pressure for flushing, which can vary in pressure from day to day and from site to site.

US Patent 5587053 referred to above discloses a jet arrangement which removes the usual pump and pipework of a whirlpool tub. The arrangement involves a complex jet assembly which includes a motor and an impeller so that it is the jet that creates the turbulence. The jet is removable for cleaning. While this patent provides benefits by removing the pump and pipework of a typical whirlpool tub, the jets are expensive, and are awkward to remove and replace after each bathing session. They also require education in relation to removing and replacing the jets, which requires some skill. The arrangement is also prone to parts breaking and parts being lost or misplaced, while it also requires homeowners or staff of commercial operations to remember to remove the jets for cleaning. This arrangement is not user friendly and is not automated and can be easily overlooked when it comes to cleaning time.

It is an object of the present invention to provide an improved arrangement for hygienic cleaning of recirculation systems employed for example in whirlpool tubs and recirculating showers.

SUMMARY OF THE INVENTION

The present invention provides a recirculation system including pipework having an inlet arranged to receive liquid for recirculation and an outlet to which the liquid is delivered, the system further including a valve arrangement for closing the inlet and the outlet, a sanitizer inlet for introducing sanitizer into the pipework and a pumping arrangement to pump sanitizer within the pipework.

A major benefit of the present invention, is provided by the valve arrangement for closing the inlet and the outlet, because that enables the sanitizer to be introduced into the recirculation system to flood the system and to remain in the system, either in a standing or a recirculating condition for the appropriate period. That is, the use of the valve arrangement to close the inlet and outlet of the pipework, means that sanitizer that is introduced into the pipework can be captured within the pipework rather than escaping from it. Thus, the sanitizer does not flush out of the system, but is introduced into the system and remains in the system until the valve arrangement opens the inlet and/or the outlet for discharge of the sanitizer.

If the recirculation system of the invention is associated with a recirculating shower, such as of the kind disclosed in Applicant's co-pending US application 12/310,889 referred to above, the pipework inlet can be at a suction inlet of a shower base while the pipework outlet can be at the shower head or nozzle. In that arrangement, with each of the inlet and outlet closed by the valve arrangement, sanitizer can be introduced into the pipework and the pumping arrangement of the recirculating shower and be left to sit within the pipework and the pumping arrangement for the required time for proper sanitizing.

Alternatively, a pipework loop can be formed so that the sanitizer can recirculate through the pipework for the required time for proper sanitizing. Once that time has elapsed, the valve arrangement can open the inlet and/or the outlet and allow the sanitizer to flow out of the pipework. In the recirculating shower of Applicant's co-pending US application 12/310,889, this could be through the outlet 8 illustrated in Figure 2 and this could be under the effect of gravity or pumping pressure. The sanitizer would then be discharged into the waste outlet and thus removed from the recirculation system.

Alternatively, if the recirculation system is associated with a whirlpool tub, the pipework inlet can be the suction in-take of the tub, while the pipework outlet can be the one or more jets. As with the recirculating shower discussed above, closure of the pipework inlet and outlets can advantageously allow the recirculation system to be thoroughly flooded with sanitizer for sanitizing the system.

It is to be noted that the sanitizing solution that is introduced into the pipework can be flushed from the pipework after sanitizing is complete, or in some systems it can be left within the pipework until the bathing or showering device to which the recirculation system is fitted is used next. Accordingly, the recirculation system can include facility to discharge and flush the sanitizer immediately after the completion of a sanitizing operation, or it can be set up to discharge the sanitizer as the next use of the bathing or showering device is made. This might involve a flushing of the recirculation system as a first step when the bathing or showering device is next operated and before water is discharged into the whirlpool tub reservoir or though the shower head. This can apply to showering devices for example, in which it is usual to turn the shower on and discharge cold water out through the head while awaiting arrival of the hot water.

The valve arrangement can take any suitable form in order to close the inlet and outlet of the recirculation system. The valves could be operated automatically as part of an overall automated sanitizing system, or they can be manually operated. In some forms of the invention, the valve arrangement includes valves that are rated to open when they are subjected to a certain pressure. In these forms of the invention, the valves could be rated to open when the liquid pressure applied to them reaches the normal liquid pressure at which the bathing or showering device is operated. Clearly such devices can be operated through a range of pressures and so the valves could be rated to open when the liquid pressure applied to them reaches the lowest realistic operating pressure. With this arrangement, when the sanitizer is introduced into the pipework, it is introduced at a pressure which is less than the pressure at which the valves open, ie less than the lowest realistic operating pressure of the device, so that the valves remain closed and the sanitizer remains within the pipework without discharge through the valves.

The valves can be non-return valves. These can be spring operated, magnetic, elastic, tube seal or diaphragm non-return valves. The valves can be ball, butterfly or gate valves. The valves can be motorized such as through solenoid operation.

As an example of the pressures that would apply in a normal recirculation system to which the invention might be employed, during normal operation of a whirlpool tub, the recirculating pressure pump will normally produce in excess of 5 psi, typically 7 - 13psi at a flow rate of around 200 - 350 Ipm, although higher capacity pumps can produce up to 43 psi with flow rate of around 300 - 350 Ipm.. Accordingly, in a whirlpool tub to which the invention has been employed, at these pressure ranges, the valve arrangement would allow flow of water through each of the inlet and the outlet of the pipework, ie through each of the suction in-take of the tub and the jets. In recirculating showers, the recirculating pressure pump will normally produce 40 - 100 psi and likewise, within this pressure range the valve arrangement would allow flow of water through each of the drain of the shower base into the pipework and out of the shower head or nozzle. Below these pressures however, the valve arrangement would close against flow. The invention can provide that when the recirculating pressure pump is turned off, the valve arrangement closes the inlet and the outlet. In respect of a whirlpool tub, closure of the valves of the valve arrangement allows the sanitizing process to commence. Accordingly, with the valves of the valve arrangement closed, the tub can be drained of the water that was used to bathe in through the normal drain outlet, and thereafter, the sanitizing process can be commenced. Thus, sanitizer can be introduced into the pipework through the sanitizer inlet and the pumping arrangement can pump the sanitizer within the pipework. The pumping arrangement will limit the pressure of the sanitizer to below that which would open the valves of the valve arrangement, so that the sanitizer is maintained within the pipework rather than being discharged out of the jets of the tub and into the reservoir. The pressure could be limited to below 5 psi for example.

Once the sanitizer has flooded the pipework completely, the sanitizer can be left standing in this condition for the required time, such as 1 to 5 minutes for example, although sanitizers requiring greater or lesser contact time can be employed. If necessary, the pumping arrangement can operate to maintain a head of pressure to ensure that the flood is maintained. Alternatively, the sanitizer can be recirculated about the pipework for the required time. Once the required sanitizing time has been reached, fresh water is introduced into the recirculation system at an increased the pressure within the system, to force open one or more of the valves of the valve arrangement, so as to flush the sanitizer out of the recirculation system. The sanitizer can then flow through the normal drain of the recirculating bathing or showering device. Alternatively, a separate sanitizer drain can be included for draining the sanitizer. Alternatively, as explained above, the sanitizer can be left within the recirculation system for flushing out of the system as an initial step the next time the bathing or showering device is used.

The pumping arrangement of the recirculation system can comprise the pump of the whirlpool tub or recirculating shower, or an additional pump or pumps can be employed. A separate and low capacity pump is preferred for the recirculation system to ensure that the pressure of recirculation is maintained below the pressure at which the valves of the valve arrangement will open. Such a pump can also be employed for flushing the sanitizer out of the recirculation system, although the pump of the recirculating bathing or showering device could be used for this purpose or mains pressure water could also be used.

Where an additional pump is provided, it would typically be of significantly reduced capacity relative to the pump of the whirlpool tub or recirculating shower. However, the pump can have any suitable capacity and for example, a pump capacity of between 20 litres per minute (Ipm) and 1001pm could be employed. However, depending on the application, the capacity could be in the region of llpm to 2001pm The system can be restricted to the introduction of a single charge of a sanitizer solution, either in a concentrated form, powder or liquid for example, for mixing with water that is introduced into the recirculation system at the same time. Fresh water could be used, or the water from the bathing or showering device that is being sanitized could be used. Alternatively, the sanitizer can be in a form which can be introduced into the recirculation system to fill the system without additional mixing. Alternatively, the sanitizing solution can comprise one of a plurality of solutions that are introduced into the system, degreasers or abrasives for example, for complete cleaning of the system. The introduction of additional solutions might require additional solution inlets and pumps.

While the sanitizer has been described above as a powder or a liquid, it is possible that it could alternatively be a gas, such as ozone. It is to be understood that the invention encompasses any form of sanitizer, regardless of its state.

Another advantage of the invention is that the type of sanitizer that can be used can be different that is used in the prior art. In the prior art, some more aggressive sanitizers are not used despite their better performance, because they can degrade the surface of whirlpool tub fittings that project into the reservoir of the tub, such as by tarnishing brass fittings for example. However, by containing the sanitizer within the recirculation system, advantageously the fittings are not affected by the sanitizer.

All of the steps described above in relation to sanitizing the recirculation system of a bathing or showering device can be automated, so that a single initiation step can commence the sanitizing process. This can be as simple as a switch or button which the user of the device can actuate upon finishing bathing or showering, or which can be operated by cleaning personnel when conducting other cleaning activities. The system could be arranged so that following initiation of the sanitizing process by actuating the switch or button, the system completes the process without further external involvement. The system can thus be set up to require no expertise at all. The system could even be arranged to commence operation automatically upon sensing that a bathing or showering activity has been completed, so that no manual actuation to start the sanitizing process is required. For a whirlpool tub, the system could be arranged to commence operation upon complete draining of the tub. For a recirculating shower, the system could be arranged to commence operation upon sensing that the person showering has left the shower.

Moreover, the present invention is expected to be available at a lower cost than some other current systems and can be fitted to existing recirculating bathing or showering devices.

It will be understood that the recirculation system of the invention could be employed in commercial arrangements in which multiple showers are provided in a showering facility. This might apply in sports gyms for example. Each shower might have a dedicated sanitizing system, or a single sanitizing system might service two or more showers. The same applies to whirlpool tubs, such that a single sanitizing system might service two or more tubs.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention and to show how it may be performed, embodiments thereof will now be described, by way of non-limiting example only, with reference to the accompanying drawings.

Figure 1 is a schematic plan of the invention as it applies to a whirlpool tub. Figures 2 to 4 illustrate valve arrangements applicable to whirlpool tub jets. Figures 5 and 6 illustrate valve arrangements applicable to whirlpool tub suction intakes. Figure 7 illustrates a port arrangement for a jet discharge eyeball, which facilitates better cleaning.

Figures 8 to 14 illustrate various views and components of a valve of the present invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic plan of a circulation system according to the invention as applied to a whirlpool tub 11. The whirlpool tub 11 is illustrated as having a body of water 12 therein.

A whirlpool tub of typical construction includes a pump, which has a suction in-take and a discharge outlet. The pump is connected to the whirlpool tub to draw water out of the tub and to discharge that water under pressure back into the tub through jets or nozzles. The discharge flow may be variable at the selection of the bather, as is the direction of discharge through the jets or nozzles.

Often whirlpool tubs are used with bath oils or salts, to increase the therapeutic benefits of the tub, or simply to provide a more enjoyable bathing experience. Such salts and oils are thus sucked out of the whirlpool tub and into the pump, for discharge back into the tub through the jets or nozzles.

In addition to the salts and/or oils that might enter the recirculation system, body fats, oils, skin tissue and other body fluids can also enter the recirculation system and be recirculated through that system from the suction inlet to the discharge outlets. As explained above, these fats, oils etc can collect on surfaces of the recirculation system, i.e. within the suction inlet and discharge outlet, and within the pipework and pump. Accordingly, a residue can form on surfaces of the recirculation system which can compromise the sanitary condition of the system so that subsequent users of the tub might unknowingly bath in potentially unhygienic water. While certain residues that might collect in the recirculation system are essentially harmless to subsequent bathers, there is the possibility that the residue could form harmful bacteria that could affect the health of subsequent bathers. In addition, the formation of bacteria is often associated with the generation of unpleasant odour.

The system 10 as illustrated in Figure 1 includes a sanitising arrangement for sanitising the recirculation system of the tub 11.

The recirculation system 10 includes a main pump 13, which is the pump that is used to draw water out of the tub 11 and to discharge it under pressure through jets 14 during normal operation of the tub 11. The jets 14 open through the wall of the tub 11 and typically are substantially flush with the wall. Pipework or plumbing extends from the pump 13 to each of the jets 14 for the delivery of water to the jets 14. In Figure 1, the pipework line 15 extends from the pump 13 and connects in series to each of the jets 14.

In a recirculation system that does not employ the sanitising arrangement of the present invention, the line 15 would terminate at the final jet 14, and water would be drawn out of the tub 11 through a suction in-take 16 for delivery back to the pump 13 through the return line 17. Water is recirculated in this manner for the period of time that the pump 13 is operated and when bathing is over, the pump 13 is switched off and the water 12 within the tub 11 can be drained out of the tub 11 through the drain outlet 18.

In Figure 1, the sanitising arrangement which has been applied to the recirculation system 10 includes a connecting line 20 which extends from the line 15 which supplies the jets 14, to the return line 17 via a valve 21 and a recirculation pump 22. During normal operation of the tub 11, the valve 21 is closed, so that the recirculation system 10 operates without flow through the line 20. Thus, water is drawn out of the tub 11 through the suction in-take 16, through the line 17 to the pump 13 for 15 pressurised discharge through the line 15 to the jets 14.

However, in sanitising mode, the valve 21 is opened to form a flow loop comprising the lines 15, 17 and 20.

With the valve 21 opened, it will be appreciated that with the pump 13 operating, water will still be discharged through the jets 14 and will be sucked into the in-take 16. Accordingly, for sanitizing the recirculation system 10, it is necessary to close each of the jets 14 and the intake 16 and the applicant has developed a variety of valve arrangements for that purpose. Cross-sectional representations of five proposed valves are shown in Figures 2 to 6, and reference will now be made to those drawings.

Figure 2 illustrates a section of the wall 25 of the tub 11 of Figure 1. The wall section 25 includes an opening within which is disposed a jet 26. The jet 26 comprises a mounting jet body 27 and an eyeball 28, which can be fixed or rotatable. The jet body 27 is secured to the wall 25 via screws 29, although other forms of fixing could easily be employed.

Disposed within the jet body, is a non-return valve 30 which comprises a polymer valve element 31 and a valve seat 32. The valve element 31 is secured in place by the seat 32, which can form part of the eyeball 28 or jet body 27.

The valve element 31 is formed as a tube, which is arranged to close at the leading end thereof under low pressure conditions. This closed condition is illustrated in Figure 2, in which the leading end 33 of the element 31 is shown in a collapsed or closed form. Figure 2A shows the valve element 31 in an open form, with water being discharged through the element 31 and this open condition is assumed when the pressure behind the element 31 is above a predetermined lower level.

The valve element 31 can be formed of any suitable material that collapses and opens in the manner described above. It is expected that the material of the element 31 will be a polymer, such as a silicone based rubber, santoprene or any flexible material that can withstand chemical sanitizers, slats, salts, oils, ozone etc. The valve element 31 can be arranged to close and open at any suitable pressure. For the purposes of the present invention and as it applies to whirlpool tubs, the valve element 31 is expected to be designed to close when the pressure behind the element reduces to 5 psi or below. Conversely, water pressures above 5 psi will cause the valve element to open as shown in Figure 2A and to allow discharge of water through the jet 26 with minimal resistance. In order to assist closure of the valve element 31, a magnetic arrangement could be employed thus, a magnet which is fixed to either side of the leading end 33 could be employed, so that when the back pressure falls below 5 psi, the magnetic elements attract each other to close the leading end 33.

With reference to Figure 3, this represents a variation on the arrangement of Figure 2, and thus the same reference numerals have been used for the same parts. In the Figure 3 arrangement, the valve element 35 is formed in a similar but slightly different manner to the valve element 31 of Figure 2, by including a leading end portion 36 which is formed to roll into itself. It is the provision of this rolling portion of the leading end that could provide better sealing of the valve when the pressure behind the element 31 reduces to 5 psi or below.

Figure 4 represents a further alternative valve arrangement, and again like parts from Figures 2 and 3 are given the same reference numerals. In Figure 4, the jet 40 is of a magnetic kind, and is hinged to the seat 32 so as to rotate between open and closed conditions. The hinge can be a pin hinge for example, or the hinge could be a resiliently flexible material, such as a rubber flap.

The flap 41 supports a magnetic element 42, while a structural member 43 (shown in more detail in Figure 4A), supports a second magnetic element 44 or a magnetically attractive material. With reference to Figure 4A, the structural member 43 is formed in a cross configuration and it connects to or is formed integrally with the internal surface of the eyeball 28, although it could alternatively connect to the seat 32 or the internal surface of the cylindrical portion 45 of the jet body 27.

Each of the magnetic elements 42 and 44 are attractive to each other. In addition, either through a hinge which is resiliently biased towards closing the flap 41, or through gravity, the flap 41 tends to a closed position in which the magnetic elements 42 and 44 are closely adjacent or in contact. The magnetic attraction between the elements 42 and 44 is selected to allow the flap 41 to shift to an open condition upon the pressure behind the valve 40 exceeding a predetermined pressure, such as exceeding 5 psi. In Figure 4, the flap 41 is shown in a partially open condition and in practice, the flap 41 would continue to rotate towards a horizontal orientation as water flows through the eyeball 28. As soon as the water flow terminates, or the pressure behind the flap 41 is reduced a sufficient level, the flap 41 will return to the closed position. The magnetic attraction between the elements 42 and 44 is provided to maintain the flap in the closed position until the pressure behind the valve 40 exceeds the predetermined level. The magnetic attraction is not intended to return the flap 41 back to the closed position, although of course as the magnetic elements 42 and 44 approach each other, the magnetic attraction between them will strengthen.

The valves disclosed in Figures 2 to 4 have all been developed in relation to the jets of a whirlpool tub. Figures 5 and 6 disclose valves which have been developed for use in a suction in-take of a whirlpool tub. Like the earlier valves of Figures 2 to 4, the valves of Figures 5 and 6 are examples only and could be replaced by other valves such as motorised valves. With reference to Figure 5, a section of tub wall 50 is illustrated which includes an opening for accommodating a suction in-take. The in-take is illustrated as a suction in-take 16 in Figure 1 and is usually disposed towards the bottom of the tub 11 of Figure 1. The in-take illustrated in Figure 5 comprises a cover or grate 51 that is provided to prevent unintended entry of foreign objects through the in-take (hair, fingers, toes, jewellery etc), but which allows flow of water from within the tub through the in-take. Accordingly, the grate 51 is formed as a grill or mesh or the like.

The grate 51 includes a cylindrical body 52 within which is disposed a valve 53. The valve 53 is a magnetic valve of a similar kind to the valve 40 of Figure 4, and includes a flap 54 which is in hinged connection to a structural member 55 that is formed in a cross configuration of the same kind as the structural member 43 of Figure 4 and 4A.

The structural member 55 supports a magnetic element 56, while the flap 54 also supports a magnetic element 57. The flap 54 thus operates in the same manner as the flap 41 of the valve 40, except that water flow through the arrangement of Figure 5 is in the opposite direction to the direction of flow through the respective valves of Figures 2 to 4 as indicated by the arrow A.

Figure 6 illustrates an alternative valve arrangement to that illustrated in Figure 5, and is very similar to the arrangement illustrated in Figure 2. In Figure 6, the same reference numerals are used for like parts from Figure 5. In Figure 6, a polymer valve 60 is illustrated having the same construction as the valve 30 illustrated in Figure 2. Thus, the valve 60 is formed of a polymeric material and is seated at its circumference, against a valve seat 61.

In Figure 6, the valve 60 is shown in a closed condition, in which the leading end of the valve 62 is collapsed into closure. As pressure behind the valve 60 increases, the valve end 62 will open in the manner shown in Figure 2A with respect to the valve 30 and allow the passage of water flow through the valve 60.

The valves described in relation to Figures 2 to 6 can be employed as appropriate in the jets

14 and the suction in-take 16. However, the valves are examples only and other valve constructions could be employed. For example, one or more of the valves can be motorised such as by solenoid drive, and the valves could be ball or gate valves. Alternatively, the valves can be manually closable from within the tub such as by rotating or pulling/pushing the valve. Alternatively, caps, plugs or stoppers could be employed.

Returning to Figure 1, the sanitising arrangement of the invention will be further described.

In Figure 1 a sanitiser reservoir 70 is shown in fluid communication through line 71 with the pipework line 15. Between the reservoir 70 and the line 15, a back flow prevention valve 72 is provided, along with an actuation valve 73. When it is appropriate to introduce sanitising liquid into the line 15, the valve 73 is opened, and sanitiser flows through the line 71 and into the line 15. The back flow prevention valve 72 prevents liquid flowing through the line

15 from entering the reservoir 70. A further fluid line 80 is illustrated and this line is connected to a supply of fresh water, such as a mains supply. The line 80 includes an inlet line 81 and branch lines 82 and 83.

In each of lines 82 and 83, back flow prevention valves 84 are disposed to prevent entry of liquid flowing through the line 15 into the lines 82 and 83. Actuation valves 85 are also provided for opening the lines 82 and 83 when required. Pressure reducing valves 86 are provided to reduce the inlet pressure through the line 81, which in most cases will be mains pressure at about 40psi or above. The pressure reducing valve 86 in the line 82 provides pressure reduction to 5psi or below, while the pressure reducing valve 86 in the line 83 provides pressure reduction to a pressure well above this, but which can be mains pressure or below.

The system illustrated in Figure 1 operates as follows. Once bathing in the whirlpool tub 11 is finished, the water 12 within the tub 11 is drained through the drain outlet 18. Because there is little or no back pressure, the valves associated with the jets 14 and the suction intake 16 will close, either automatically by the drop in pressure, or by the valve being actuated electrically or manually. The sanitising system can then be actuated which firstly involves draining the existing liquid contained within the flow lines 15 and 17 (although this is optional as the system can be commenced with the existing liquid contained within the flow lines 15 and 17), opening the valve 21, opening the valve 73 and allowing sanitising liquid to flow into the flow line 15 through the flow line 71. Fresh water is introduced into the recirculation system through the flow line 82 and the pump 22 is operated to recirculate the sanitizer and water through the system.

Once the lines 15, 17 and 20 are flooded, including the pump 13 and at least the rear sections of the jets 14 and the valve in the suction in-take 16, the pump 22 can be shut down if required, or the pump 22 can continue to run and circulate liquid about the lines 15, 17 and 20, for a period that is required for the sanitising fluid to take effect.

After the required duration, usually between 1 and 5 minutes, the sanitising liquid within the recirculation system can be drained through drainage line 87, following opening of valve 88. To fully remove the sanitising solution, fresh water can be introduced through the line 83 into the line 15 and flushed about the system under mains pressure. The mains pressure will open the valves which close the jets 14 and the suction in-take 16 for flushing the lines 15, 17 and 20. Alternatively, the main pump 13 can be operated with the same effect. Thus, the sanitizer can be flushed into the tub 11 for draining through the drain outlet 18.

With the system flushed, fresh water can be maintained within the lines 15, 17 and 20, or they can be drained completely. If complete draining is required, the lines 15, 17 and 20 can drain to a low point at the flow-line 87, so that drainage can take place under gravity.

It will be appreciated that the valves which close the jets 14 and the suction in-take 16 operate automatically, depending on the liquid pressure to which they are exposed. The respective valves are either open or shut depending on that pressure. In addition, each of the actuation valves can be electrically operated, as can the pumps 13 and 22. Accordingly, the system can be a completely automatic system, which is initiated by a one step action, such as pressing a button or flicking a switch. The system is thus extremely user friendly and requires little or no skill. Sensors can be employed to monitor the amount of sanitiser within the sanitiser reservoir 70 to indicate when replenishment of sanitiser is required. A timer can be employed to maintain the system flooded or to operate the system in recirculation mode for the appropriate period.

Advantages of the arrangement illustrated in Figure 1 are significant. Firstly, by use of the system of the invention, complete filling of the tub 11 twice for flushing of the recirculation system is no longer required. Rather, all that is required is to flood the actual system and this could result in savings in the order of 700 litres of water per clean. In addition, with the system automated as discussed above, the system is extremely simple to operate and foolproof.

In addition, the valves, examples of which are illustrated in Figures 2 to 6, can be easily removed and cleaned as they are of simple construction and of relatively few moving parts.

Figure 7 illustrates a particular form of jet discharge which can also be easily cleaned. The Figure 7 illustration is of a jet discharge 90, which comprises an eyeball 91, an angled connecting conduit 92 and a conduit section 93 which is connected into the general plumbing of a whirlpool tub.

As is evident from Figure 7, the connecting conduit 92 is disposed at an angle to the conduit section 93, whereby if a standard cleaning device is inserted into the opening 94 of the eyeball 91, the cleaner can travel up the conduit 92 and slide into the conduit section 93 with ease.

The Figure 7 arrangement differs from prior art arrangements which either employ a connecting conduit 92 which is perpendicular to the conduit section 93, or which do not include a connecting conduit 92 at all. In that prior art, a cleaner inserted into the opening 94 of eyeball 91 would abut the internal surface of the conduit section 93 at right angles and not allow, or would be difficult to produce a back and forth cleaning movement within each of the eyeball 91, the connecting conduit 92 and the conduit section 93. The arrangement thus allows a pipe cleaner to be pushed through the connecting conduit 92 and well into the conduit section 93 for the removal of build-up within that section, as well as within the connecting conduit 92 and the eyeball 91.

Throughout the description and claims of the specification the word "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives, components, integers or steps.

The invention described herein is susceptible to variations, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the present disclosure. Features may be added to or omitted from the provisional claims at a later date so as to further define or re-define the invention or inventions.

Claims

1. A recirculation system including pipework having an inlet arranged to receive liquid for recirculation and an outlet to which the liquid is delivered for discharge, the system further including a valve arrangement for closing the inlet and the outlet, a sanitizer inlet for introducing sanitizer into the pipework and a pumping arrangement to pump sanitizer within the pipework.

2. The recirculation system of claim 1, the inlet being an opening formed in a shower recess and the outlet being a shower head.

3. The recirculation system of claim 1, the inlet being a suction in-take of a whirlpool tub and the outlet being one or more discharge jets of the whirlpool tub.

4. The recirculation system of claim 3, the recirculation system including a first pump for pumping liquid through a delivery flowline for delivery of liquid to the discharge jets and a suction flowline in liquid communication with the suction in-take and the first pump for delivery of liquid to the first pump from the suction in-take, a connecting flowline in liquid communication with the delivery flowline and the suction flowline so as to form a flow loop through the respective suction, delivery and connecting flowlines, and a flow loop valve disposed in the flow loop so that with the flow loop valve closed, flow through the flow loop is terminated.

5. The recirculation system of claim 4, the flow loop valve being disposed in the connecting flowline, so that with the flow loop valve closed, flow through the connecting flowline is terminated and flow through the flow loop is consequently terminated.

6. The recirculation system of claim 4 or 5, the recirculation system further including a second pump of reduced capacity relative to the first pump for circulating sanitizer through the flow loop.

7. The recirculation system of claim 6, the first pump having a capacity of 200 to 5001pm and the second pump having a capacity of 1 to 2001pm.

8. The recirculation system of claim 6 or 7, the second pump being positioned in the connecting flowline.

9. The recirculation system of any one of claims 3 to 8, the recirculation system including a drain that is selectively openable to drain sanitizer from the recirculation system.

10. The recirculation system of any one of claims 3 to 9, the valve arrangement including a valve positioned in each of the discharge jets or behind the discharge jets.

11. The recirculation system of claim 10, the discharge jets having an inlet and an outlet relative to the direction of discharge of liquid through the jets and the valves being positioned proximal to the outlet.

12. The recirculation system of any one of claims 1 to 11, the valve arrangement including non-return valves which open to allow flow through the valves when back pressure behind the valves exceeds a predetermined minimum pressure and close when the back pressure returns to below the predetermined pressure.

13. The recirculation system of claim 12, the minimum pressure being about 5psi.

14. The recirculation system of claim 12 or 13, the non-return valves being spring operated, magnetic, elastic, tube seal or diaphragm non-return valves, or motorized or electric operated ball, butterfly or solenoid valves, or manually closable valves.

15. The recirculation system of any one of claims 1 to 14, the sanitizer inlet being valve controlled and facilitating flow of sanitizer from a reservoir into the pipework through a valve when the valve is opened.

16. The recirculation system of any one of claims 1 to 15, the system further including a fresh water inlet for introducing fresh water into the pipework to flush the pipework of sanitizer.

17. A method of sanitizing a recirculation system which includes pipework having an inlet arranged to receive liquid for recirculation and an outlet to which the liquid is delivered for discharge, the method including closing the inlet and the outlet and introducing sanitizer into the pipework to at least substantially fill the pipework.

18. The method of claim 17, wherein the inlet and the outlet are closed by valves.

19. The method of claim 18, the valves being non-return valves.

20. The method of any one of claims 17 to 22, the method including recirculating the sanitizer through the pipework

21. The method of any one of claims 17 to 20, the sanitizer being within the pipework for a period of at least 1 minute.

22. The method of any one of claims 17 to 20, the sanitizer being within the pipework for a period of about 5 minutes.

23. The method of any one of claims 17 to 22, the method including flushing the sanitizer from the pipework with fresh water.