The present invention relates to a rainwater collection tank, and to a rainwater collection system, and in particular, though not limited to a rainwater collection system for collecting rainwater flowing from a rainwater gulley or gutter into a downpipe.

Throughout this specification, the term "downpipe" shall be understood to encompass any type of drainage pipe installed in or on the side of a building to direct rainwater from a roof or a surface to a municipal drainage system or storm drain. In particular, the term "downpipe" shall be understood to also refer to any drainage apparatus which is used to direct water from a roof space down through the internal structure of a building, where the downpipe may be encased within the building walls and structures so that access to the downpipe is prohibited or extremely limited.

Increasingly, governments and local authorities around the world are treating water as a scarce commodity and water charges are being introduced as a means to cover the cost of treating and supplying water to residential and business properties. Water metering is carried out in approximately two-thirds of the OCED (Organisation for Economic Co-operation and Development) countries already and many of the remaining countries, including Ireland, have plans to introduce water metering. Consequently, the capture and treatment of rainwater has become of interest in recent times. There are many types of rainwater harvesting systems known in the public domain. Typically rainwater is captured from a roof or large planar surface area and is passed under gravity to a storage tank at or below ground level. This captured rainwater must then be treated and is typically pumped back to a water storage tank in an attic or service room close to the top of the building so that the water pressure in the building is created naturally under gravity. The water storage tank to which the treated rainwater is pumped must be kept separate from a town's mains water storage tank in the attic, and from the town's mains water supply in a house or building.

Instead of pumping the rainwater from the rainwater storage tank at ground level, it has also been envisaged to collect rainwater flowing through existing downpipes and other existing infrastructures. There are a number of advantages to this. The existing downpipes and drainage system may be used by the rainwater collection system such that any overflows or the like may be simply passed into the downpipe and on to the municipal drainage system. Furthermore, the facade of the building is not greatly affected as much of the rainwater collection system may be installed within the downpipe so that the device is concealed from view.

A number of rainwater harvesting systems which utilise existing downpipes on a building are known from Australian Patent Publication No. AU 2011211452 A1 (Morgan); British Patent Publication No.

GB 2,476,281 A (Bridge); British Patent Publication No. GB 2,483,522 A (Blakes); British Patent Publication No. GB 2,449,534 A (O'Driscoll); European Patent Publication No. EP 2,208,830 A (Hashimoto); and PCT Published Application No. WO 2013/045673 A of the present applicant. Australian Patent Publication No. AU 2011211452 A1 discloses rainwater collectors which function to store and divert rainwater that would otherwise not be utilised around the property. The rainwater collectors of AU 2011211452 A1 are modified downpipes which allow storage of rainwater for later use. The rainwater collectors disclosed in AU 2011211452 A1 may alternatively be used to divert rainwater to larger storage systems such as water tanks or water gardens using a simple, gravity based conduit system. The rainwater collectors of AU 2011211452 A1 comprise an overflow pipe such that any excess rainwater may be directed to municipal drainage systems as necessary.

The problem with the rainwater collector of AU 2011211452 A1 is that the system is extremely basic and does not allow for any control over the distribution of the collected rainwater. Furthermore, direct access to the downpipe is required in order to install the rainwater collector of AU 2011211452 A1 and this is not always possible, particularly in the case of large commercial buildings were the downpipes may be encased within concrete walls and structures of the building.

British Patent Publication No. GB 2,476,281 A discloses a rainwater collection and storage system in which rainwater which is run off from a roof of a building is collected and stored in a system of gutters and downpipes which are adapted to retain the rainwater as well as divert excess rainwater to a municipal drainage system. The rainwater preferably passes through a filter into the downpipe which is in fluid communication with the system by means of a standard pipe. A one-way valve may be provided to prevent backflow from a mains water supply into the rainwater collection and storage system supply. GB 2,476,281 A also discloses diverting rainwater directly from the downpipes to a toilet and the like by means of a standard size pipe.

As before, the control of the flow of the rainwater collected by the rainwater collection and storage system of GB 2,476,281 A is absent. This absence of any control is undesirable as the rainwater will flow under gravity along the path of least resistance, which requires a complicated conduit system to be arranged. This could require extensive works to an existing building in order to install the gravity-based rainwater collection and storage system. Furthermore, the rainwater collection and storage system of

GB 2,476,281 A requires access to the downpipes and cannot be retrofit to existing buildings where the access to the downpipes is prohibited or extremely limited.

British Patent Publication No. GB 2,483,522 A discloses a gutter downpipe for rainwater collection and remote release of the collected rainwater. The gutter downpipe is installed in place of a regular downpipe, and the gutter downpipe of GB 2,483,522 A is a modular and stackable unit which preferably includes an attachment means for attaching the modular and stackable units to a structure or a building. An electronics module is used to open and close a motorised valve in the gutter downpipe in order to release collected rainwater from the gutter downpipe. Whilst the gutter downpipe of GB 2,483,522 A address some of the control issues surrounding earlier examples of downpipe-based rainwater collectors, the control is rudimentary and crude. Furthermore, GB 2,483,522 A refers to the collection of rainwater down along the side of a building from the downpipe. The gutter downpipe therefore has to be attached to the side wall of the building which is unsightly. Additionally, rainwater collected by this system tends to contain silt and debris, which results in blockages in downstream plumbing systems. Furthermore, the system disclosed in British Specification No.

2,483,522 provides no flow control of the rainwater, and also requires altering of the external fabric of the building to facilitate its installation.

As it is known for large industrial sized buildings having substantially flat roofing to use downpipes through the building itself, the prior art rainwater collections systems which are used with downpipes are not suited to be used with substantially flat roofs. As mentioned hereinbefore, in large commercial buildings, a large flat roof may have a number of downpipes extending downwardly through the building at several locations. Oftentimes, these downpipes are encased in the fabric of the building, for example, in concrete forming a part of the building structure and cannot be accessed. Therefore, prior art solutions cannot be applied to these types of downpipes.

European Patent Publication No. EP 2,208,830 A discloses a rainwater collection system for use in a building with a flat roof whereby water drains from the flat roof into a rainwater gulley, and in turn from the rainwater gulley into a downpipe formed within the fabric of the building. A rainwater collection tank is located in the downpipe, and an upper flange of the collection tank engages the top end of the downpipe. The flange defines a rainwater inlet to the collection tank, and rainwater from the rainwater gulley flows into the collection tank through the rainwater inlet and is collected therein. A conduit extends from the rainwater collecting tank to a rainwater storage tank for delivering rainwater collected in the rainwater collection tank to the rainwater storage tank. An inlet end of the conduit is located within the rainwater collection tank adjacent a lower end thereof, and a pump at the inlet end of the conduit pumps rainwater from the rainwater collection tank through the connecting conduit to the rainwater storage tank. However, the rainwater collection system disclosed in European Specification No. 2,208,830 is a low volume system. It provides a source of rainwater for watering plants. Additionally, because of the relatively low capacity of the rainwater collection tank in the downpipe, the collection tank can fill relatively rapidly, and due to a lack of rapid overflow arrangement from the collection tank, the rainwater can back up from the collection tank into a gulley or gutter from which the downpipe extends, and in turn overflow from the gulley or gutter with serious consequences. Furthermore, the submersion of the pump in the collection tank can lead to serious damage to the pump, should the ambient temperature drop below freezing point.

PCT published Application No. WO 2013/045673 discloses a rainwater collection system which is also suitable for a flat roof building. A rainwater gulley collects water from the flat roof and channels the rainwater into a downpipe. A rainwater collection tank is located in the downpipe and extends into the downpipe from the upper end thereof. A housing comprising a pump and a control system is located in the gulley, and a connecting conduit extending from the pump into the rainwater collection tank pumps water from the rainwater collection tank to a rainwater storage tank. The rainwater storage tank is located in the gulley.

While the rainwater systems of EP 2,208,830 A and WO 2013/045673 are suitable for use in collecting rainwater from a flat roof whereby one or more downpipes extend from a rainwater gulley in the flat roof through the fabric of a building, they still suffer from a number of disadvantages, for example, both systems tend to consume a considerable amount of power, and should water freeze in the rainwater collection tank, expansion of the ice in the rainwater collection tank can result not only in damage to the rainwater collection tank, but can also result in damage to the downpipe, which can subsequently result in water leaking from the downpipe into the fabric of the building, and in turn into the building. There is therefore a need for a rainwater collection system, which is suitable for collecting rainwater from a flat roof, which addresses at least one of the problems of the prior art. The present invention is directed towards such a rainwater collection system, and the invention is also directed towards a rainwater collection tank. Furthermore, the invention is directed towards a building comprising the rainwater collection system.

According to the invention there is provided a rainwater collection tank comprising a tubular housing dimensioned to fit within a downpipe, and having a base and a peripheral wall extending around and upwardly from the base and defining with the base a primary hollow interior region for holding rainwater, a rainwater inlet communicating with the primary hollow interior region, wherein the peripheral wall tapers downwardly. Preferably, the peripheral wall tapers along substantially its entire length.

In one aspect of the invention the peripheral wall tapers at an angle in the range of 1° to 6°. Preferably, the peripheral wall tapers at an angle in the range of 2° to 5°. Advantageously, the peripheral wall tapers at an angle of approximately 4°.

In another aspect of the invention the peripheral wall defines a transverse cross-section of the tubular housing in plan view, the shape of which is substantially similar to the shape of the transverse cross- section of the downpipe in plan view. Preferably, the peripheral wall defines a transverse cross-section of the tubular housing in plan view of substantially circular cross-section.

In another aspect of the invention the peripheral wall defines a transverse cross-section of the tubular housing in plan view of substantially square cross-section.

In an alternative aspect of the invention the peripheral wall defines a transverse cross-section of the tubular housing in plan view of substantially rectangular cross-section.

In a further aspect of the invention the peripheral wall defines a transverse cross-section of the tubular housing in plan view of substantially polygonal cross-section. Preferably, the peripheral wall defines the rainwater inlet. Advantageously, the rainwater inlet is located adjacent an upper end of the tubular housing. Ideally, the rainwater inlet is configured to face in a generally upwardly direction. Preferably, the peripheral wall tapers from the rainwater inlet.

In another aspect of the invention the peripheral wall terminates at its upper end in an upper end edge, and the upper end edge of the peripheral wall defines the rainwater inlet.

In another aspect of the invention a flange extends around and outwardly from the peripheral wall adjacent the upper end thereof, the flange being configured to engage one of an upper end of the downpipe and a gulley or a gutter from which the downpipe extends. Preferably, the flange is configured to sealably engage the one of the upper end of the downpipe and the gulley or the gutter.

Advantageously, the rainwater inlet extends through the flange. Ideally, the peripheral wall tapers from the flange.

In another aspect of the invention a float controlled valve is provided responsive to level of rainwater rising above a predefined overflow level for discharging water from the primary hollow interior region.

The invention also provides a rainwater collection tank comprising a tubular housing dimensioned to fit within a downpipe, the tubular housing defining a primary hollow interior region for holding rainwater, a rainwater inlet communicating with the primary hollow interior region, and a float controlled valve responsive to level of rainwater rising above a predefined overflow level for discharging water from the primary hollow interior region. In one aspect of the invention the tubular housing comprises a base and a peripheral wall extending around and upwardly from the base and defining with the base the primary hollow interior region.

In another aspect of the invention an outlet port is provided from the primary hollow interior region, and the float controlled valve comprises a valving member co'operable with the outlet port for releasably sealing the outlet port. Preferably, a valve seat is located adjacent the outlet port, and the valving member is releasably sealably engageable with the valve seat. Advantageously, the valve seat extends around the outlet port. In another aspect of the invention a float of the float controlled valve is connected to the valving member by a first connecting means.

In a further aspect of the invention an urging means is provided for urging the valving member into sealable engagement with the valve seat. Preferably, the urging means comprises a weight suspended from the valving member. Advantageously, the urging means is connected to the valving member by a second connecting means, the second connecting means extending through the outlet port with the urging means located externally of the tubular housing. In another aspect of the invention the outlet port is located adjacent a lower end of the tubular housing. Preferably, the outlet port is located in the base of the tubular housing, and the urging means is located beneath the base.

In another aspect of the invention the valving member defines a central axis, and the first connecting means and the second connecting means extend from the valving member substantially along the central axis defined by the valving member.

In another aspect of the invention the first and second connecting means comprises an elongated carrier rod, the valving member being carried on the carrier rod intermediate the ends thereof, and a portion of the carrier rod extending upwardly from the valving member defines the first connecting means, and a portion of the carrier rod extending downwardly from the valving member defines the second connecting means.

Preferably, the portion of the carrier rod defining the first connecting means terminates in the float. Advantageously, the portion of the carrier rod defining the second connecting means terminates in the urging means.

Preferably, a sealing means is provided for providing a substantially watertight seal between the valving member and the valve seat.

Advantageously, the valving member comprises a valving disc. Preferably, the valving member is of substantially circular shape. In one aspect of the invention a guide means is provided for guiding the float controlled valve. Preferably, the guide means comprises a guide bracket secured to the tubular housing. Advantageously, a guide bore is provided in the guide bracket engageable with one of the first and second connecting means for guiding the float controlled valve.

In another aspect of the invention a sub-housing is located on the base over the outlet port, the sub- housing defining a secondary hollow interior region with which the outlet port communicates, at least one communicating opening being provided in the sub-housing communicating the secondary hollow interior region of the sub-housing with the primary hollow interior region.

In another aspect of the invention the sub-housing comprises a side wall extending around the outlet port, and the at least one communicating opening is located in the side wall, the side wall extending upwardly to a top wall.

Advantageously, the sub-housing forms the guide bracket, and the guide bore is provided in the sub- housing co-operable with the first connecting means for guiding the first connecting means.

In another aspect of the invention the valving member is urgeable by the float from a closed state closing the outlet port to an open state with the outlet port open. Preferably, the valving member is urgeable by the urging means from the open state to the closed state.

In one aspect of the invention a collar extends around and upwardly from the rainwater inlet, the collar comprising at least one communicating opening having a filter means located therein for filtering rainwater passing through the communicating opening to the rainwater inlet.

The invention also provides a rainwater collection tank comprising a tubular housing dimensioned to fit within a downpipe, and defining a primary hollow interior region, and a rainwater inlet to the primary hollow interior region, and a collar extending around and upwardly from the rainwater inlet, the collar comprising at least one communicating opening having a filter means located therein for filtering rainwater passing through the communicating opening to the rainwater inlet.

Preferably, the filter means in each communicating opening comprises a mesh material. In one aspect of the invention at least one projecting element extends from the collar adjacent a corresponding one of the communicating openings for engaging and retaining leaves spaced apart from the communicating opening in the collar. Preferably, a plurality of projecting elements extend from the collar.

In another aspect of the invention each projecting element comprises an elongated member of length in the range of 5mm to 15mm, and of maximum cross-sectional dimension in the range of 1mm to 3mm. Advantageously, each projecting element comprises an elongated member of length in the range of 8mm to 12mm, and of maximum cross-sectional dimension in the range of 1mm to 2mm. Preferably, each projecting element comprises an elongated member of length of approximately 10mm, and of maximum cross-sectional dimension of approximately 2mm.

Further the invention provides a rainwater collection system comprising a rainwater collection tank according to the invention.

In one aspect of the invention a rainwater storage tank is provided and a communicating means connects the rainwater storage tank to the rainwater collection tank for transferring rainwater from the rainwater collection tank to the rainwater storage tank. In another aspect of the invention the communicating means is configured to transfer the rainwater from the rainwater collection tank to the rainwater storage tank by syphonic action.

In a further aspect of the invention a pump is provided in the communicating means to initiate the syphonic action. Preferably, the pump is configured to operate for a predefined initiating time period to initiate syphonic flow of water through the communicating means from the rainwater collection tank to the rainwater storage tank.

In another aspect of the invention the predefined initiating time period lies in the range of 2 seconds to 30 seconds. Preferably, the predefined initiating time period lies in the range of 3 seconds to 20 seconds. Advantageously, the predefined initiating time period is approximately 5 seconds.

In a further aspect of the invention a control means is provided for controlling operation of the pump. In one aspect of the invention a rainwater level sensing means is provided for detecting the level of rainwater in the primary hollow interior region of the rainwater collection tank, the control means being responsive to the first level sensing means detecting the rainwater level in the rainwater collection tank rising to a predefined pumping level to activate the pump to commence pumping for the predefined initiating time period.

In a further aspect of the invention the pump and the control means are located in a main housing, the main housing being configured for mounting on one of a rainwater gulley in a roof of a building and a flat roof of a building.

In another aspect of the invention the main housing is configured for mounting over the downpipe with the rainwater collection tank extending into the downpipe.

Preferably, the rainwater collection tank is suspended from the main housing.

In another aspect of the invention the main housing is supported on at least three support legs.

Preferably, the main housing is supported on four support legs. Advantageously, the support legs are configured for adjusting the height of the main housing above the downpipe. In another aspect of the invention at least one mounting bracket extends downwardly from the main housing for carrying the rainwater collection tank. Preferably, each mounting bracket is configured for adjusting the spacing between the main housing and the rainwater collection tank.

In another aspect of the invention the rainwater storage tank is located at a level below the level of the rainwater collection tank. Preferably, the pump is located at a level above the level of the rainwater collection tank and the rainwater storage tank.

In one aspect of the invention the communicating means comprises a connecting conduit extending between an inlet end and an outlet end, the connecting conduit being located with the inlet end thereof located in the primary hollow interior region of the rainwater collection tank and the outlet end extending from the primary hollow interior region. Preferably, the outlet end of the connecting conduit is connected to an inlet port of the pump. Advantageously, the inlet end of the connecting conduit is located adjacent a lower end of the rainwater collection tank. In a further aspect of the invention the communicating means comprises a delivery conduit for delivering rainwater from the pump to the rainwater storage tank. Preferably, the delivery conduit is connected at one end to an outlet port of the pump, and at the other end thereof to the rainwater storage tank.

Additionally the invention provides a rainwater collection system comprising a rainwater collection tank dimensioned to fit within a downpipe, the rainwater collection tank defining a primary hollow interior region for holding rainwater, a rainwater inlet communicating with the primary hollow interior region for receiving rainwater into the primary hollow interior region, a rainwater storage tank, and a communicating means communicating the rainwater collection tank with the rainwater storage tank, the communicating means being configured for transferring rainwater from the rainwater collection tank to the rainwater storage tank by syphonic action.

Preferably, a first rainwater level sensing means is provided for detecting the level of rainwater in the primary hollow interior region of the rainwater collection tank, the control means being responsive to the first level sensing means detecting the rainwater level in the rainwater collection tank rising to a predefined pumping level to activate the pump to commence pumping for the predefined initiating time period. In one aspect of the invention a rainwater filtration means is provided for filtering rainwater being transferred from the rainwater storage tank.

In one aspect of the invention the rainwater filtration means comprises one or more of the following types of filters:

a sand filter,

a cotton block filter, and

a carbon block filter.

Preferably, the rainwater filtration means comprises at least two of the types of the filters arranged in the sequence the sand filter, the cotton block filter and the carbon block filter.

Advantageously, the rainwater filtration means comprises each of the sand filter, the cotton block filter and the carbon block filter arranged in the sequence commencing with the sand filter and terminating in the carbon block filter.

In another aspect of the invention the rainwater filtration means comprises an ultraviolet filter.

Advantageously, the ultraviolet filter is located downstream of the one or more of the sand filter, the cotton block filter and the carbon block filter.

In another aspect of the invention a mixing means co-operating with a chlorine source is provided for dosing the rainwater passing from the rainwater storage tank with a predefined amount of chlorine. In a further aspect of the invention a water softening means is provided for softening the rainwater passing from the rainwater storage tank.

Preferably, a second water level sensing means is provided in the rainwater storage tank, and the control means is responsive to the second water level sensing means for disabling flow of rainwater from the rainwater collection tank to the rainwater storage tank.

Further the invention provides a building comprising the rainwater collection system according to the invention, the building comprising a roof, and a downpipe extending from the roof, and the rainwater collection system is located on the roof with the rainwater collection tank extending downwardly into the downpipe.

The invention will be more clearly understood from the following description of an embodiment thereof, which is given by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a schematic view of a rainwater collection system according to the invention,

Fig. 2 is a cross-sectional side elevational view of a part of the rainwater collection system of Fig. 1, Fig. 3 is a top plan view of the part of the rainwater collection system of Fig. 2 with a portion of the rainwater collection system removed,

Fig. 4 is a perspective view of a portion of the part of the rainwater collection system of Fig. 2, Fig. 5 is an underneath perspective view of a portion of the part of the rainwater collection system of Fig. 2, Fig. 6 is a cutaway perspective view of a portion of a rainwater collection tank also according to the invention of the rainwater collection system of Fig. 1,

Fig. 7 is an underneath perspective view of a portion of the rainwater collection tank of Fig. 6, Fig. 8 is a top perspective view of a portion of the rainwater collection tank of Fig. 6,

Fig. 9 is a cutaway perspective view of a detail of the rainwater collection tank of Fig. 6,

Fig. 10 is another cutaway perspective view of a detail of the rainwater collection tank of Fig. 6,

Fig. 11 is a perspective view of another detail of the rainwater collection tank of Fig. 6,

Fig. 12 is a perspective view of a portion of the part of the rainwater collection system of Fig. 2, Fig. 13 is another perspective view of a portion of the part of the rainwater collection system of

Fig. 2,

Fig. 14 is a cross-sectional side elevational view of the rainwater collection tank of Fig. 6, and Fig. 15 is a block representation of electrical and electronic control circuitry of the rainwater collection system of Fig. 1.

Referring to the drawings, there is illustrated a rainwater collection system according to the invention, indicated generally by the reference numeral 1 , for collecting and storing rainwater from a flat roof 3 of a building 5 also according to the invention. A plurality of rainwater gulleys, only one of which rainwater gulleys 6 is illustrated, are formed in the flat roof 3 and collect rainwater from the flat roof 3 and in turn channel the rainwater into a plurality of downpipes 8, only one of which downpipes 8 is illustrated. The downpipe 8 may extend downwardly from the rainwater gulley 6 through the fabric of the building, or may extend downwardly within the building and be encased within a suitable casing. Alternatively, the downpipe may extend downwardly from the rainwater gulley 6 along an outside wall of the building 5. However, in this case, the downpipe 8 extends through the fabric of the building 5. The rainwater collection system 1 comprises a rainwater collection tank 10 also according to the invention, which is located in the downpipe 8 as will be described below for collecting rainwater delivered into the downpipe 8 from the rainwater gulley 6. A rainwater storage tank 12 is located in the building at a level below the level of the flat roof 3, and below the level of the rainwater collection tank 10 for receiving rainwater from the rainwater collection tank 10 as will be described below, although it will be understood that the rainwater storage tank 12 may not necessarily be located in the building, it may be located externally of the building, but, in general, will be located in the immediate vicinity of the building.

A main housing 14 is supported on four support legs 15 extending downwardly from the main housing 14, which engage the flat roof 3 adjacent the rainwater gulley 6. The main housing 14 is located above the downpipe 8 with the rainwater collection tank 10 suspended from the main housing 14 and extending downwardly into the downpipe 8.

A pump 16 located in the main housing 14 initiates flow of rainwater from the rainwater collection tank 10 for delivering the rainwater from the rainwater collection tank 10 to the rainwater storage tank 12.

Because of the relative levels of the rainwater collection tank 10 and the rainwater storage tank 12, once flow is initiated from the rainwater collection tank 10 to the rainwater storage tank 12 by the pump 16, flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12 continues by syphonic action. Before describing the delivery of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12, the components of the rainwater collection system 1 will first be described.

Turning initially to the rainwater collection tank 10, the rainwater collection tank 10 comprises a tubular housing 18 having a circular base 19 and a peripheral wall 20 extending around and upwardly from the base 19, and defining a longitudinally extending main central axis 17. The base 19 and the peripheral wall 20 define a primary hollow interior region 21 within which the rainwater is collected. The peripheral wall 20 terminates at its upper end in an upper end edge 22 which defines a rainwater inlet 24 to the primary hollow interior region 21 for accommodating rainwater therethrough into the primary hollow interior region 21. The rainwater collection tank 10 is dimensioned to fit into the downpipe 8, and in general, the peripheral wall 20 is shaped to define a transverse cross-section of the rainwater collection tank 10 in plan view, which is of shape similar to the shape of the transverse cross-section of the downpipe 8 in plan view. In this embodiment of the invention the downpipe 8 is of circular transverse cross-section in plan view, and accordingly, the peripheral wall 20 of the rainwater collection tank 10 similarly defines the transverse cross-section of the rainwater collection tank 10 in plan view to be of circular cross-section. Although it will be readily apparent to those skilled in the art that while it is desirable that the transverse cross-section of the rainwater collection tank 10 should be of similar shape to the transverse cross-section of the downpipe, this is not essential.

In this embodiment of the invention the peripheral wall 20 of the rainwater collection tank 10 tapers downwardly from the upper end edge 22 of the tubular housing 18 to the base 19. By tapering the peripheral wall 20 downwardly from the upper end edge 22 of the tubular housing 18 to the base 19, there is no danger of ice resulting from rainwater freezing in the rainwater collection tank 10 damaging the rainwater collection tank 10 as the ice expands, nor is there any danger of ice as it expands in the rainwater collection tank 10 damaging the downpipe 8. Any expansion of ice in the rainwater collection tank 10 due to the downward tapering of the peripheral wall 20, and in turn the primary hollow interior region 21 causes the freezing and expanding ice to creep upwardly in the primary hollow interior region 21, in other words, to be urged upwardly in the primary hollow interior region 21 and in turn through the rainwater inlet 24 without damaging the tubular housing 18, and in turn without damaging the downpipe 8. In this embodiment of the invention the tapering angle defined by the peripheral wall 20 is 4°. In other words, the cone angle defined by the tapering peripheral wall 20 is 4°. The cone angle is sometimes referred to as the creep angle, and in order to avoid any doubt, the cone angle of 4° in this case is formed by opposite portions of the peripheral wall 20 inclining inwardly downwardly at an angle of 2° relative to the main central axis 17 to thereby produce a cone angle of 4°. However, it will be readily apparent to those skilled in the art that the peripheral wall 20 may taper with a cone angle of any desirable value within the range of 1 ° to 6°. However, when selecting the cone angle of the tapering of the peripheral wall 20 of the tubular housing 18, a compromise must be reached between the angle required in order to ensure that freezing expanding ice is urged upwardly through the primary hollow interior region 21 of the tubular housing 18 through the rainwater inlet 24, and maximising the volume of the primary hollow interior region 21 of the tubular housing 18. It has been found that a cone angle of approximately 4° is the optimum cone angle.

A circular flange 25 extends around and outwardly from the peripheral wall 20 of the tubular housing 18 adjacent the upper end edge 22 thereof for engaging a top edge 27 of the downpipe 8 and the rainwater gulley 6 in order to anchor the rainwater collection tank 10 in the downpipe 8, and to prevent the rainwater collection tank 10 falling into the downpipe 8. The flange 25 is clearly illustrated in Fig. 14. An O-ring seal 28, of a suitable sealing material, for example, neoprene or rubber, is located between the flange 25 and a portion of the rainwater gulley 6 around the top edge 27 of the downpipe 8, so that rainwater from the rainwater gulley 6 must first pass into the rainwater collection tank 10 before passing through the downpipe 8. The O-ring seal 28 is clearly illustrated in Fig. 14.

A float controlled valve 30 controls the level of the rainwater in the primary hollow interior region 21 of the rainwater collection tank 10 and on the level of rainwater exceeding a predefined overflow level, the float controlled valve 30 is operated for discharging rainwater from the rainwater collection tank 10 into the downpipe 8. In some embodiments of the invention, and in particular in this embodiment of the invention, where a rising level of rainwater in the rainwater gulley 6 can be tolerated, the float controlled valve 30 is configured only to operate for discharging rainwater from the rainwater collection tank 10 into the downpipe 8 in response to the rainwater backing up from the rainwater collection tank 10 into the rainwater gulley 6, and reaching the predefined overflow level in the rainwater gulley 6. The predefined overflow level in the rainwater gulley 6 is indicated in Figs. 1 and 14 by the reference numeral 32. In this embodiment of the invention the predefined overflow level 32 in the rainwater gulley 6 is reached when the depth of rainwater in the rainwater gulley 6 adjacent the downpipe 8 reaches approximately 15mm. However, in cases where a rising level of rainwater is not tolerated in a rainwater gulley, on a flat roof, or in a gutter, the predefined overflow level would normally be a level of rainwater within the primary hollow interior region 21 of the rainwater collection tank 10.

A circular outlet port 31 is formed in the base 19 through which rainwater is discharged from the rainwater collection tank 10 into the downpipe 8. The outlet port 31 is concentric with the base 19 and with the main central axis 17. The float controlled valve 30 comprises a valving member, namely, a circular valving disc 33 which is co-operable with the outlet port 31 for releasably sealing the outlet port 31, see Figs. 9 and 10. A portion of the base 19 extending around the outlet port 31 forms a valve seat 34. A sealing means, namely, an O-ring seal 36 of a suitable sealing material, for example, neoprene or rubber, sits on the valve seat 34 and co-operates with the valving disc 33 for sealably closing the outlet port 31.

In this embodiment of the invention the valving disc 33 is mounted fast on and concentrically with an elongated carrier rod 37 which extends through the valving disc 33. An upper portion 38 of the carrier rod 37 extends upwardly from the valving disc 33, and terminates at its upper end in a float 39, thereby forming a first connecting means for connecting the valving disc 33 to the float 39. The float 39 is mounted on the upper portion 38 of the carrier rod 37 so that the distance between the float and the valving disc 33 is such that as the rainwater begins to rise above the predefined overflow level 32 in the rainwater gulley 6, the float 39 urges the valving disc 33 upwardly from a closed state with the valving disc 33 sealably engaging the O-ring seal 36 closing the outlet port 31 to an open state disengaged from the O-ring seal 36 opening the outlet port 31 for discharging rainwater from the primary hollow interior region 21 of the rainwater collection tank 10 into the downpipe 8 until the level of rainwater in the rainwater gulley 6 falls below the predefined overflow level 32. A lower portion 40 of the carrier rod 37 extends downwardly from the valving disc 33 and terminates in an urging means, namely, a weight 41 , and thus acts as a second connecting means for connecting the weight 41 to the valving disc 33, for in turn urging the valving disc 33 into the closed state. The weight of the weight 41 is such that for so long as the rainwater level in the rainwater gulley 6 remains below the predefined overflow level 32, the weight 41 retains the valving disc 33 in the closed state. However, the weight of the weight 41 is such that as the level of rainwater in the rainwater gulley 6 commences to rise above the predefined overflow level 32, the weight 41 does not prevent the float 39 rising with the rising rainwater level for urging the valving disc 33 into the open state.

A sub-housing 44 mounted on the base 19 and extending above the outlet port 31 is concentric with the main central axis 17 and defines a secondary hollow interior region 45 which communicates with the outlet port 31 , see Figs. 9 and 10. The sub-housing 44 comprises a cylindrical side wall 46 extending around the outlet port 31 and upwardly from the base 19 to a top wall 47 which with the side wall 46 defines the secondary hollow interior region 45. A plurality of communicating openings 48 are formed in the side wall 46 for communicating the secondary hollow interior region 45 with the primary hollow interior region 21. A guide means, namely, a guide bore 50 in the top wall 47 of the sub-housing 44 slideably engages the upper portion 38 of the carrier rod 37 for guiding the carrier rod 37 as the valving disc 33 is being urged between the closed state and the open state, and for retaining the guide rod 37 substantially coinciding with the main central axis 17 of the rainwater collection tank 10. However, it is envisaged that in many cases, the sub-housing 44 may be dispensed with, and the guide means would be provided by a suitable guide bracket which would include a guide bore for slideably engaging the carrier rod 37. Depending on the location of the guide bracket, whether it would be located within the primary hollow interior region of the rainwater collection tank, or externally thereof beneath the base 19, the guide bore in the guide bracket would be configured to slideably engage either the upper portion 38 or the lower portion 40 of the carrier rod 37. It is also envisaged that a filter means, for example, a gauze filter of metal mesh may be provided in the communicating openings 48 for filtering the rainwater as it passes from the primary hollow interior region 21 of the tubular housing 18 into the secondary hollow interior region 45 defined by the sub- housing 44. Indeed, it is also envisaged that the sub-housing 44 could be formed of a self-supporting metal gauze material. The provision of such a metal gauze material, whether the metal gauze material formed the sub-housing, or was provided in the communicating openings 48, would filter the rainwater passing from the primary hollow interior region 21 to the secondary hollow interior region 45, thereby avoiding any danger of dirt or debris lodging in the valve seat or on the O-ring of the outlet port 31, which could otherwise inhibit the valving disc 33 sealably closing the outlet port 31.

A protective collar 54 extends upwardly from the flange 25 around the rainwater inlet 24, and is provided with a plurality of communicating openings 55 for accommodating water from the rainwater gulley 6 of the roof 3 into the rainwater collection tank 10 through the rainwater inlet 24. A filter means comprising a panel 56 of a metal gauze material of mesh of between 2mm and 5mm is located in each communicating opening 55 for filtering out debris and other particulate matter from the rainwater prior to the rainwater entering the rainwater collection tank 10. A plurality of projecting elements 58 (see Figs. 2 and 14) extend radially outwardly from the protective collar 54 for engaging and retaining leaves spaced apart from the protective collar 54, and in turn from the communicating openings 55 through the collar 54, in order to avoid any danger of leaves or other similar matter blocking the communicating openings 55 of the protective collar 54. The projecting elements 58 in this embodiment of the invention are of circular transverse cross-section of diameter of approximately 1mm to 2mm and of length of approximately 10mm.

A support bracket 59 extends across the primary hollow interior region 21 of the rainwater collection tank 10 between opposite sides of the peripheral wall 20 thereof adjacent the rainwater inlet 24, and is provided with a first central bore 60 coinciding with the main central axis 17 of the rainwater collection tank 10 for slideably engaging and for retaining the carrier rod 37 coinciding with the main central axis 17 of the rainwater collection tank 10, and for guiding the guide rod 37, and in turn the valving disc 33 between the closed and open states. A second bore 61 is provided in the support bracket 59 for engaging a connecting conduit 62 which is described in more detail below.

As mentioned above, the rainwater collection tank 10 is suspended from the main housing 14, and a pair of mounting brackets 63 extending downwardly from and secured to the main housing 14 are secured to the protective collar 54. Each mounting bracket 63 comprises an elongated downwardly extending member 64 which is secured to the protective collar 54 by one or more screws 65 with nuts 57. An elongated slot 66 in the member 64 of each mounting bracket 63 facilitates adjustment of the spacing between the main housing 14 and the protective collar 54 and in turn the rainwater collection tank 10. A sidewardly extending member 67 extends sidewardly from the downwardly extending member 64 of each mounting bracket 63 and is secured to the main housing 14 by screws 68. An elongated slot 69 in the side member 67 of each mounting bracket 63 accommodates adjustment of the mounting brackets 63 on the main housing 14 for facilitating alignment of the rainwater collection tank 10 with the downpipe 8.

Turning now to the main housing 14, the main housing 14 comprises a base wall 70, a pair of spaced apart side walls 71 extending upwardly from the base wall 70 joined by a pair of spaced apart end walls 72 extending upwardly from the base wall 70 between the side walls 71. A lid 73 hingedly coupled to one of the side walls 71 closes the main housing 14. The four support legs 15 are of L-shaped construction and comprise an upstanding limb 74 and a sidewardly extending limb 75. The sidewardly extending limbs 75 form feet which engage the rainwater gulley 6 or the roof 3, depending on the width of the rainwater gulley 6 for supporting the main housing 14 thereon above the downpipe 8. Slots 76 in the side limbs 75 accommodate screws (not shown) or other suitable fasteners for securing the legs 15 to the rainwater gulley 6 or the roof 3 as the case may be. Slots 77 in the upstanding limbs 74 accommodate screws 78 for securing the legs 15 to the main housing 14. The slots 77 allow for adjustment of the height of the main housing 14 above the rainwater gulley 6, and in turn above the rainwater collection tank 10.

The pump 16, which is located in the main housing 14, along with the connecting conduit 62 and a delivery conduit 85 together form a communicating means, which connects the rainwater collection tank 10 with the rainwater storage tank 12, and through which rainwater is transferred from the rainwater collection tank 10 to the rainwater storage tank 12. The connecting conduit 62 extends between an inlet end 79 and an outlet end 80. The connecting conduit 62 extends into the rainwater collection tank 10 through the second bore 61 in the support bracket 59 and extends downwardly into the rainwater collection tank 10 so that the inlet end 79 is located in the lower end of the rainwater collection tank 10 adjacent the base 19 of the rainwater collection tank 10. The outlet end 80 of the connecting conduit 62 is connected to an inlet port 83 of the pump 16 through a water meter 97, which is discussed below. A pipe accommodating opening 96 formed in the base wall 70 accommodates the connecting conduit 63 into the main housing 14. The delivery conduit 85 which extends between an inlet end 86 and an outlet end 87 is connected between the pump 16 and the rainwater storage tank 12 for delivering rainwater from the pump 16 to the rainwater storage tank 12. The inlet end 86 of the delivery conduit 85 is connected through a non-return valve 84 to an outlet port 88 of the pump 16, while the outlet end 87 of the delivery conduit 85 is connected to the rainwater storage tank 12.

As discussed above, the rainwater storage tank 12 is located in the building 5, typically in an attic space beneath the flat roof 3 of the building 5, or above a false ceiling within the building at a level below the rainwater collection tank 10. Therefore once the pump 16 initiates flow of rainwater from the rainwater collection tank 10 through the connecting conduit 62, the pump 16 and the delivery conduit 85, flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12 continues as a result of syphonic flow. As will be described below, the pump 16 is operated for a predefined initiating time period of between 5 seconds and 30 seconds in order to initiate syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. At the end of the predefined initiating time period, with syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12 established, the pump 16 is deactivated and syphonic flow of the rainwater continues until the level of rainwater drops below the inlet end 79 of the connecting conduit 62.

A non-return valve 89 is located in the inlet end 79 of the connecting conduit 62 in order to maintain the connecting conduit 62 filled with water between the inlet end 79 and the pump 16 even when the level of rainwater in the rainwater collection tank 10 falls below the level of the inlet end 79 of the connecting conduit 62, in order to facilitate quick initiation of the syphonic flow when the pump 16 is next activated to initiate syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. A filter 82 is located at an inlet (not shown) to the non-return valve 89 in the inlet end 79 of the connecting conduit 62 for filtering rainwater being drawn into the connecting conduit 62 through the non-return valve 89. The filter 82 is of size in order to filter out particles of size greater than 1 mm to 2mm from the rainwater passing from the primary hollow interior region 21 of the tubular housing 18 into the connecting conduit 62.

A heating means, in this embodiment of the invention comprising two elongated electrically insulated electrically resistive heater wires 90 are located in and extend through the connecting conduit 62 from the inlet end 79 thereof to the outlet end 80 for heating water in the connecting conduit 62 when the ambient temperature drops below a predefined temperature, typically, 3°C in order to avoid freezing of rainwater in the connecting conduit 62. Although not illustrated in the drawings, a pair of electrically insulated electrically resistive heater wires, similar to the heater wires 90 are located in and extend through the delivery conduit 85 from the inlet end 86 to the outlet end 87 thereof, for heating water in the delivery conduit 85 when the ambient temperature drops to the predefined temperature of 3°C, in order to avoid rainwater in the delivery conduit 85 freezing.

Turning now to the control of the operation of the rainwater collection system 1 , a control means, namely, an electronic controller, in this case a microcontroller 91 is located in the main housing 14 for controlling operation of the rainwater collection system 1. A first level sensing means, namely, a first electric field level sensor 93 is mounted on the peripheral wall 20 within the primary hollow interior region 21 of the rainwater collection tank 10, for detecting when the level of rainwater in the primary hollow interior region 21 of the rainwater collection tank 10 reaches a predefined pumping level adjacent the first level sensor 93. The microcontroller 91 reads signals from the first level sensor 93, and on the level of rainwater in the primary hollow interior region 21 reaching the predefined pumping level 92, the microcontroller 91 operates the pump 16 for the predefined initiating time period of approximately either 5 seconds or 30 seconds, in order to establish syphonic flow of rainwater from the rainwater collection tank 10 to Ihe rainwater storage tank 2 through the connecting and delivery conduits 62 and 85. Syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12 continues until the water level in the primary hollow interior region 21 of the rainwater collection tank 10 drops below the level of the inlet end 79 of the connecting conduit 62. Initially to prime the system, the microcontroller 91 is programmed to operate the pump 16 for a first predefined initiating time period of approximately 30 seconds, in order to initially initiate syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. Once the connecting conduit 62 is filled with water which is retained by the non-return valve 82 located in the inlet end 79 of the connecting conduit 62, a second predefined initiating time period of approximately 5 seconds is sufficient to initiate syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. Thus, the microcontroller 91 is programmed to reduce the predefined initiation time period from 30 seconds, after the rainwater collection system 1 has been primed to a second predefined initiating time period of approximately 5 seconds. However, in some rainwater collection systems according to the invention, it may be necessary to programme the microcontroller 91 to increase the second predefined initiating time period to be longer than 5 seconds. However, this is carried out during setting up of the rainwater collection system. A second level sensing means, namely, a second ultrasonic level sensor 94 located in the rainwater storage tank 12 monitors the level of rainwater in the rainwater storage tank 12. The microcontroller 91 reads the signals from the second level sensor 94, and on the signals from the second level sensor 94 being indicative of the level of rainwater in the rainwater storage tank 12 reaching a predefined maximum level, indicating that the rainwater storage tank 12 is full, the microcontroller 91 is programmed to terminate syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. Termination of syphonic flow may be carried out in a number of ways. A shut-off valve (not shown) may be located in the delivery conduit 85, which would be operated under the control of the microcontroller 91 to shut off the syphonic flow of rainwater through the delivery conduit 85. Alternatively, a valve may be located adjacent the inlet port 83 of the pump 16 which would be operated under the control of the microcontroller 91 to momentarily admit air into the pump 16 in order to break the syphonic flow. An alternative arrangement would be to programme the microcontroller 91 to deactivate the rainwater collection system 1 on the level of rainwater in the rainwater storage tank 12 reaching a predefined level, which would still allow a further predefined volume of rainwater to be admitted into the rainwater storage tank 12 prior to the level of rainwater in the rainwater storage tank 12 reaching the maximum predefined level. The level at which the microcontroller 91 would be programmed to deactivate the rainwater collection system 1 would be such that the volume of rainwater required to bring the level of rainwater in the rainwater storage tank 12 from the cut-off level to the predefined maximum level would equate to a known maximum amount of rainwater which would be transferred by syphonic action from the rainwater collection tank 10 to the rainwater storage tank 12 before the level of rainwater in the rainwater collection tank 10 fell below the inlet end 79 of the connecting conduit 62, irrespective of the flow rate of water from the rainwater gulley 6 into the rainwater collection tank 10. A temperature sensor 95 located externally on the main housing 14 monitors ambient temperature, and the microcontroller 91 reads signals from the temperature sensor 95, and on the signals from the temperature sensor 95 being indicative of the ambient temperature dropping to 3°C, the microcontroller 91 powers up the heater wires 90 in order to avoid freezing of the water in the connecting conduit 62, and also in the rainwater collection tank 10. The heater wires 90 are maintained powered up by the microcontroller 91 for so long as the ambient temperature remains at or below 3°C. The heater wires in the delivery conduit 85 are also powered up by the microcontroller 91 in response to the ambient temperature dropping to 3°C, and are maintained powered up by the microcontroller 91 until the ambient temperature rises above 3°C. The water meter 97 which is connected between the outlet end 80 of the connecting conduit 62 and the inlet 83 of the pump 16 monitors and measures the flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. Signals from the water meter 97 are read by the microcontroller 91 which stores data from the water meter 97 indicative of the flow rate and the quantity of rainwater delivered from the rainwater collection tank 10 to the rainwater storage tank 12. The data stored by the microcontroller 91 from the water meter 97 may be stored in a memory of the microcontroller 91 or in a suitable separate external electronic data storage memory 99. A communication module 98 is located in the main housing 14 and is operated under the control of the microcontroller 91 for communicating wirelessly with external devices, for example, a mobile phone, a computer, a laptop computer, a tablet computer or other such device. Where communication is by way of a mobile phone network, the communications module 98 is provided as a GSM based transceiver with a SIM card. Alternatively or additionally, the communication module may be provided with a radio transceiver for providing two-way wireless communication. The wireless communication may be by way of any suitable protocol, for example, Wi-Fi, Bluetooth, conventional radio waves or by any other suitable wireless communication means, including other radio communications protocols, such as GSM, LTE and the like, as well as Near Field Communication protocols. The microcontroller 91 is programmed so that the status of the rainwater collection system 1 may be read from the microcontroller 91 through the communications module 98. Data which can be read from the microcontroller 91 through the communications module 98 includes the operational status of the pump 16, the current temperature read from the temperature sensor 95, the levels of rainwater in the rainwater collection tank 10 and the rainwater storage tank 12 read from the first and second level sensors 93 and 94, as well as the volume of rainwater delivered from the rainwater collection tank 10 to the rainwater storage tank 12 during selectable time periods, as well as the flow rates of the rainwater between the rainwater collection tank 10 and the rainwater storage tank 12.

The microcontroller 91, the pump 16 and other components requiring electrical power are powered by a battery pack 100 which produces a power supply at 24 volts, and comprises three rechargeable batteries 101. An electrical power source, in this embodiment of the invention a photovoltaic panel 103 is mounted on the lid 73 of the main housing 14. DC electrical power from the photovoltaic panel 103 is fed through a charge controller 104 through which the batteries 101 of the battery pack 100 are charged. An electronic power supply 105 provides a voltage regulated power supply to the microcontroller 91 of a suitable regulated voltage value.

The pump 16 and the heater wires 90 are powered directly from the battery pack 100 through relays 107 and 108, respectively, which are operated under the control of the microcontroller 91. The communications module 98 is also powered directly from the battery pack 100.

Three light emitting diodes 117, 118 and 119 are located externally on the lid 73 of the main housing 14. A first one of the light emitting diodes, namely, the first light emitting diode 117 produces a blue light when powered, and is powered up by the microcontroller 91 to indicate that the rainwater collection system 1 is operating in a standby mode. A second one of the light emitting diodes, namely, the second light emitting diode 118 glows green on being powered up, and is powered up by the microcontroller 91 to indicate that the rainwater collection system 1 is powered up and rainwater in the rainwater collection tank 10 is being delivered from the rainwater collection tank 10 to the rainwater storage tank 12. A third one of the light emitting diodes, namely, the light emitting diode 119 glows red on being powered up, and is powered up by the microcontroller 91 to indicate a fault in the rainwater collection system 1.

Referring now to Fig. 1 , the remainder of the rainwater system 1 will now be described. Rainwater from the rainwater storage tank 12 is delivered into a rainwater holding tank 120 through a feed pipe 122 which delivers the rainwater into the rainwater holding tank 120 through a ball operated float valve 123. The rainwater in the rainwater holding tank 120 is fed from the rainwater holding tank 120 through a pipeline 124 to a rainwater filtration means, namely, a rainwater filtration system 125 through which the rainwater is filtered to a level where the water exiting the filter system 125 through an outlet pipe 127 is potable water suitable for drinking.

The rainwater filtration system 125 comprises a bank of filters 110 illustrated in block representation in Fig. 1, and located in a housing 128. The bank of filters 110 comprises in series an upstream sand filter 111 , an intermediate cotton block filter 112 and a downstream carbon block filter 113. An ultraviolet filter 115 is located in the housing 128 downstream of the bank of filters 110. A water softening means, in this embodiment of the invention a water softening system 129 for treating the water passing through the filtration system 125 is located in the housing 128 downstream of the ultraviolet filter 115, although it will be appreciated that the water softening system 129 may be located in any suitable location either before or after the bank of filters 110. Indeed, in certain embodiments of the invention the water softening system may be omitted. A chlorine source 130 is also located in the housing 128, and a mixing means, namely, a mixing valve 131 is located for dosing the water passing through the filtration system 125 with a suitable predefined amount of chlorine. The mixing valve 131 is located downstream of the water softening system 129 in this embodiment of the invention, however, it will be readily apparent to those skilled in the art that the mixing valve for dosing the water with chlorine may be located upstream or downstream of the bank of filters. Indeed, in certain embodiments of the invention it is envisaged that the chlorine source and the mixing valve may be omitted.

In use, with the rainwater collection system 1 installed and powered up, the batteries 101 of the battery pack 100 are charged through the charge controller 104 by the DC electrical power supply from the photovoltaic panel 103. The pump 16 and the heater wires 90, and the heater wires (not shown) in the delivery conduit 85 are powered directly from the battery pack 100 through the relays 107 and 108, and the communications module 98 is also powered directly from the battery pack 100. The power supply 105 provides the voltage regulated power supply to the microcontroller 104, and the external electronic memory 99 for storing data under the control of the microcontroller 91. As rainwater collects in the rainwater collection tank 10, when the signal read from the first level sensor is indicative of the rainwater level having reached the predefined pumping level 92, and the signal read by the microcontroller 91 from the second level sensor 94 is indicative of the level of rainwater in the rainwater storage tank 12 being below the predefined maximum level, the microcontroller 91 activates the pump 16 for the predefined initiating time period in order to initiate syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. If the rainwater collection system 1 has not already been primed, the pump 16 is operated for the first predefined time period of approximately 30 seconds, in order to initiate the syphonic flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. Once the rainwater collection system 1 has been primed, with the connecting conduit 62 filled with water which is retained therein by the non-return valve 89, on the signal from the first level sensor 93 being indicative of the rainwater level in the rainwater collection tank 10 having reached the predefined pumping level 92 and the signal from the second level sensor 94 being indicative of the rainwater level in the rainwater storage tank 12 being below the predefined maximum level, the microcontroller 91 activates the pump 16 for the second predefined initiating time period of approximately 5 seconds. At the end of the predefined initiation time period, the microcontroller 91 deactivates the pump 16. Rainwater continues to flow by syphonic action from the rainwater collection tank 10 to the rainwater storage tank 12 for so long as the rainwater level in the rainwater collection tank 10 remains above the level of the inlet end 79 of the connecting conduit 62. Once the level of rainwater in the rainwater collection tank 10 drops below the level of the inlet end 79 of the connecting conduit 62, syphonic flow terminates, and flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12 ceases until the level of rainwater in the rainwater collection tank 10 again reaches the predefined pumping level 92 in the rainwater collection tank 10. At any stage should the rainwater exceed the predefined overflow level 32, the float 39 of the float control valve 30 commences to rise, thereby in turn urging the valving disc 33 upwardly from the valve seat 34 from the closed state to the open state to open the outlet port 31 , thereby allowing discharge of rainwater from the rainwater collection tank 10 into the downpipe 8. The float control valve 30 is held in the open state until the rainwater level falls below the predefined overflow level 32, at which stage the float controlled valve 30 is operated into the closed state by the downward urging action of the weight 41 , and is retained in the closed state by the weight 41. And so the operation of the rainwater system continues for so long as the signals read by the microcontroller 91 from the second level sensor 94 are indicative of the water level in the rainwater storage tank 12 being below the predefined maximum level.

In the event that the signals read by the microcontroller 91 from the second level sensor 94 are indicative of the level of rainwater in the rainwater storage tank 12 reaching the predefined maximum level, the microcontroller 91 terminates the syphonic flow from the rainwater collection tank 10 to the rainwater storage tank 12. This in turn results in the level of rainwater in the rainwater collection tank 10 rising, and on the level of rainwater exceeding the predefined overflow level 32, the float 39 commences to rise, thereby operating the float controlled valve 30 from the closed state to the open state to allow discharge of water directly into the downpipe 8 through the outlet port 31. The microcontroller 91 maintains the pump 16 deactivated irrespective of the level of rainwater in the rainwater collection tank 10 until the level of rainwater in the rainwater storage tank 12 drops below the predefined maximum level therein.

Termination of syphonic flow by the microcontroller 91 depends on the arrangement in the rainwater collection system for terminating the syphonic flow. If a shut-off valve is provided in the delivery conduit 85, the shut-off valve is operated by the microcontroller 91 into the closed state in order to shut off the flow of rainwater from the rainwater collection tank 10 to the rainwater storage tank 12. Additionally, the microcontroller 91 retains the pump 16 deactivated until signals from the second level sensor 94 are indicative of the level of rainwater in the rainwater storage tank 12 having dropped below the predefined maximum level. On the other hand, if a valve is provided for admitting air into the pump 16, the valve is operated under the control of the microcontroller 91 to admit air into the pump 16 to.break the siphon. In this case, the pump 16 is also retained deactivated by the microcontroller 91 until the level of rainwater in the rainwater storage tank 12 has fallen below the predefined maximum level. At any stage should the signals read from the temperature sensor 95 indicate that the ambient temperature has dropped to 3°C, the microcontroller 91 powers up the heater wires 90, and the heater wires (not shown) in the delivery conduit 85, and retains the heater wires 90 and the heater wires (not shown) in the delivery conduit 85 powered up until the signals read from the temperature sensor 95 indicate that the ambient temperature exceeds 3°C.

Should it be desired to download data from the microcontroller 91, communication is made with the microcontroller 91 through the communications module 98, and data stored by the microcontroller 91 and the external memory 99 is downloaded through the communications module 98.

The advantages of the invention are many. By configuring the rainwater collection system 1 so that rainwater is delivered from the rainwater collection tank 10 to the rainwater storage tank 12 by syphonic action, the energy requirement of the rainwater collection system 1 is minimised, since the pump 16 is only powered up for the predefined initiating time period to initiate the syphonic flow of the rainwater. By providing the tubular housing of the rainwater collection tank to taper downwardly, should water freeze in the rainwater collection tank, as the ice expands in the rainwater collection tank, the expanding ice is forced by the upwardly diverging peripheral wall 20 to creep in a generally upwardly direction through the rainwater inlet 24 from the rainwater collection tank 10, thereby avoiding any danger of the outwardly expanding ice damaging the rainwater collection tank 10.

The provision of the float controlled valve 30 provides a particularly simple and non-complex mechanism for rapidly discharging rainwater from the rainwater collection tank 10 should the level of water in the rainwater collection tank 10 or in the rainwater gulley 6, as the case may be, reach the predefined overflow level. By providing the outlet port 31 in the base, the size of the outlet port 31 can be maximised for in turn maximising the discharge rate of water from the rainwater collection tank 10.

Further advantages of the invention are as follows:

Syphonic systems require fewer outlets and downpipes than a gravity equivalent.

Collection mains can be routed horizontally through the building, no need for pipes to be fitted on a gradient.

Multiple rainwater outlets can be connected to a single downpipe with a rainwater collection tank located therein.

Up to 80% fewer downpipes are required, resulting in cost savings in materials. Also architects have more freedom with design.

Pipe diameters are smaller due to volume discharge.

Complete control over downpipe discharge location gives increased design and programme flexibility.

- Rainwater can be easily routed to collection tanks for future recycling, e.g. irrigation, fire ponds, sanitation, etc.

The connecting conduit and the delivery conduit are designed to run 100% full of water at high velocity from roof level to ground level, vastly increasing the capacity of the system when compared to traditional methods of roof drainage.

- Acceleration of construction programme and retrofit due to reduced installation period.

Designs can be varied to cater for a range of building types.

The system is technically sophisticated with each individual building requiring its own specially- designed system based on well-established hydraulic engineering principles.

Syphonic systems are self-cleansing because of the high flow rates, thereby minimising maintenance costs.

Suitable for building with internal downpipes which are generally located inside buildings which provides visual enhancement in the majority of situations.

It is envisaged that the non-return valve located between the pump and the delivery conduit may be dispensed with.

It is also envisaged that in the event of excess electricity being generated by the photovoltaic panel, the excess electricity may be fed into a mains electricity power supply network.

It is also envisaged that the rainwater collection system may be powered by mains electricity as well as or instead of battery powering.

Further, it is envisaged that while it is desirable, it is not essential that a photovoltaic panel be provided. The rainwater collection system may be powered by non-rechargeable batteries, or by rechargeable batteries, and furthermore, the rainwater collection system may be powered by mains electricity, which could also charge rechargeable batteries.

While the connecting conduit has been described as being provided with heater wires to avoid freezing of the water therein, while this is desirable, it is not essential. Similarly, the heater wires could be omitted from the delivery conduit.

It will also be appreciated that data from the level sensors and the temperature sensors may be logged on a time basis and stored for future retrieval through the communications module.

While the rainwater storage tank has been described as being located beneath the roof in an attic space or above a false ceiling beneath the roof, the rainwater storage tank may be located in any suitable location, and in certain cases, may be located at or below ground level. However, where it is desired that the flow of rainwater from the rainwater collection tank to the rainwater storage tank be by way of syphonic flow, it is essential that the rainwater storage tank be located at a level below the level of the rainwater collection tank. However, where the rainwater storage tank is not located at a level below the rainwater collection tank, the pump would be activated on the level of rainwater in the rainwater collection tank reaching the predefined pumping level, and would run continuously while the level of the rainwater in the rainwater collection tank remained above the level of the inlet end of the connecting conduit. In such cases, it is envisaged that an additional level sensor would be provided to detect when the rainwater level in the rainwater collection tank fell to the level of the inlet end of the connecting conduit. Alternatively, the first level sensor may be provided as an ultrasonic or other such level sensor, which would monitor the level of rainwater in the rainwater collection tank, and the microcontroller would determine the level of rainwater in the rainwater collection tank from signals read from the first level sensor. In which case, the microcontroller would deactivate the pump on signals from the first level sensor, or from the additional level sensor, as the case may be, being indicative of the rainwater level in the rainwater collection tank 10 having dropped to the level of the inlet end of the connecting conduit.

It is envisaged that in certain embodiments of the invention the rainwater collection tank may comprise a parallel sided tubular housing, and it is also envisaged that in other embodiments of the invention the rainwater collection tank may be provided without the float controlled valve, and in which case, overflow of rainwater from the rainwater collection tank would be accommodated by overflow outlets located adjacent a level of the rainwater collection tank at which the level of rainwater should not rise above.

While the predefined initiating time period during which the pump is operated to initiate syphonic flow has been described as being a time period of 5 seconds or 30 seconds, the predefined initiating time period may be any suitable or desired time period, and may be determined by trial and error, and will also be dependent on the combined length of the connecting conduit, the delivery conduit, and any other components located in the communicating means between the rainwater collection tank and the rainwater storage tank. In other words, the predefined initiating time period will be dependent upon the length of the rainwater path between the rainwater collection tank and the storage tank.

While the cone angle of the tapering of the peripheral wall of the tubular housing of the rainwater collection tank has been described as being a cone angle of 4°, the peripheral wall may taper downwardly at any desirable or suitable cone angle, however, typically, the cone angle at which the peripheral wall tapers downwardly will lie in the range of Γ to 6°, and preferably will lie within 3° to 5°.

Additionally, it will be appreciated that although the rainwater collection tank has been described as being of transverse cross-sectional shape similar to the transverse cross-sectional shape of the downpipe, the transverse cross-sectional shape of the rainwater collection tank may be similar to or different from the shape of the transverse cross-section of the downpipe. It will also be appreciated that the shape of the transverse cross-section of the rainwater collection tank in plan view may be of any other suitable or desired cross-sectional shape besides circular, in which case opposite walls which would make up the peripheral wall would taper downwardly to define an included angle of preferably 4°, but in general, in the range of 1° to 6°, and more preferably, in the range of 2° or 3° to 5°.

While the projecting elements for retaining leaves spaced apart from the collar which extends upwardly from the rainwater collection tank have been described as being of circular transverse cross-section, the projecting elements may be of any other suitable or desired cross-section. Additionally, while the projecting elements have been described as being of a specific length and a specific diameter, it is envisaged that the projecting elements may be of any suitable length, and typically would be of length in the range of 5mm to 15mm, and preferably, of length 8mm to 12mm. Additionally, the maximum transverse cross-sectional dimension of the projecting elements may be of any suitable or desired dimension, and typically, would lie in the range of 1mm to 3mm, and ideally, would lie in the range of 1mm to 2mm.

While the rainwater collection system has been described as comprising a bank of filters, it is envisaged in certain cases that the bank of filters may be omitted. It will also be appreciated that the bank of filters may comprise more or less or different filters to those described. While the rainwater collection system has been described as comprising an ultrasonic filter, while this is desirable, it is not essential.

While the rainwater collection system has been described for collecting rainwater in a downpipe from a rainwater gulley of a flat roof, it is envisaged that the rainwater collection system may be used for collecting water from a rainwater gulley from any type of a roof. It is also envisaged that the rainwater system according to the invention may be used for collecting water in a downpipe extending directly from a flat roof. Further, it is envisaged that the rainwater system according to the invention may be used in a downpipe extending from a gutter of a building.

While the float controlled valve has been described as being responsive to the rainwater level in the rainwater gulley being at a predefined overflow level in the rainwater gulley, in order to operate the float controlled valve for discharging water from the rainwater collection tank into the downpipe, it will be appreciated in certain uses to which the rainwater collection system is put, the predefined overflow level at which the float controlled valve is operated for discharging rainwater from the rainwater collection tank into the downpipe may be a predefined overflow level within the primary hollow interior region of the rainwater collection tank.

It will also be appreciated that any suitable guide means for guiding the float controlled valve between the open and closed state may be provided besides guide bores in the sub-housing and in the support bracket. Needless to say, the sub-housing may be omitted and replaced with a guide bracket which would be provided with a guide bore or other suitable guiding aperture for guiding the float controlled valve between the open and closed states. Needless to say, the guide means may engage either the upper portion or the lower portion of the carrier rod of the float controlled valve depending on the location of the guide means.

While the control means has been described as comprising a microcontroller, any other suitable signal processor may be provided for controlling the rainwater collection system. While the rainwater collection tank has been described as comprising a float controlled valve, in certain cases, it is envisaged that the valve for controlling discharge of rainwater from the rainwater collection tank into the downpipe may be provided by a discharge valve, which could be motor or solenoid operated, and would be operated under the control of the microcontroller in response to signals which would be read from a level sensor which would produce signals indicative of the rainwater level exceeding the predefined overflow level, whether the predefined overflow level was a level within the rainwater collection tank, or a level above the rainwater collection tank, for example, the level of the rainwater in a rainwater gulley, gutter or the like. Such a discharge valve would typically be provided in an outlet port similar to the outlet port 31, and while the outlet port could be located in any suitable location, it is envisaged that the outlet port would be located in the base of the rainwater collection tank.

Indeed, it will be appreciated that the outlet port 31 , irrespective of whether the valve is a float controlled valve or a discharge valve, may be located in any other suitable location in the rainwater collection tank.

While the rainwater collection tank has been described as comprising a flange 25 extending outwardly from the upper edge of the rainwater collection tank adjacent the rainwater inlet, it is envisaged in certain cases that the flange 25 may be omitted: In fact, in Fig. 11 the rainwater collection tank is illustrated without the flange, and in Fig. 11 the rainwater collection tank is illustrated sealed within the downpipe adjacent the top thereof by the O-ring seal 28, which is located extending around the outer surface of the peripheral wall of the rainwater collection tank between the peripheral wall and the wall of the downpipe.

The terms "comprise" and "include", and any variations thereof required for grammatical reasons, are to be considered as interchangeable and accorded the widest possible interpretation.

It will be understood that the components shown in any of the drawings are not necessarily drawn to scale, and like parts shown in several drawings are designated the same reference numerals.