AU2007234628B2 - Selectable supplementary water supply system - Google Patents

Description

AUSTRALIA F B RICE & CO Patent and Trade Mark Attorneys Patents Act 1990 SILVAN H20 PTY LTD COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Selectable supplementary water supply system The following statement is a full description of this invention including the best method of performing it known to us:- 2 Cross-Reference to Related Applications The present application claims priority from Australian Provisional Patent Application No 2006906496 filed on 21 November 2006, the content of which is incorporated herein by reference. 5 Field of the Invention This invention relates to a selectable supplementary water supply system and relates particularly to a water supply system that is able to use rain water, waste water or some other form of alternative water supply to supplement a reticulated water 10 supply. Background of the Invention Supplementary water supply systems are most desirable where water is scarce, supplies are unreliable and/or expensive. Water conservation is becoming increasingly 15 important to ensure sustainable supplies of potable water and many proposals have been made to provide supplementary supplies. A most common proposal for a supplementary water supply is to utilise rain water collected in a container or tank. Where it is inappropriate to filter and/or purify such water, it is often used for purposes other than drinking, such as for flushing toilets, 20 watering gardens and lawns, clothes washing and the like. In many proposals, a supplementary water system involves the use of a tank which is topped up, or maintained at a predetermined minimum level, with water from a reticulated town supply or other mains supply. This ensures that the supplementary supply system always has water available for the purpose for which it is installed and obviates the 25 need for a change-over valve or the like in the event the supplementary water tank runs dry. The tank may be located in a roof cavity to provide gravity feed to the outlet. Alternatively, a pump may be used to supply water to the tank outlet. In this case, the pump is operated whenever a demand for water is determined. A disadvantage of such a system is that the tank which is topped up from the 30 mains water supply (town water) is unable to take advantage of all rainfall that may occur in a particular period due to at least part of the tank containing town water. Further, where such a system relies on a pump to pump the water to the outlet, in the event of a power failure, the water supply to that outlet fails. Further, the pump is required to deliver water whenever there is demand, thus adding to the cost of operation 35 of the system. 188410_1.doc 3 Further, any water used for garden use will use a proportion of town water, depending on how much town water is in the tank, thus using this valuable resource unnecessarily. Whenever there is a connection of a mains water supply (town water) to a 5 supplementary supply system, such a connection must comply with regulations of various water authorities to ensure that there is no contamination of the town water by the supplementary water. It is therefore desirable to provide a selectable supplementing water system which avoids disadvantages of previously proposed supplementary supply systems. 10 It is also desirable to provide a supplementing water supply system which complies with the regulations of the water supply authorities. It is also desirable to provide a supplementing water supply system which is relatively economical, is simple to construct and which is efficient in operation. It is also desirable to provide a water supply system which is able to provide 15 water to those connections that are able to use stored or tank water at all times but which will not use town water for garden or similar use. It is also desirable to provide a water supply system which is able to use rain water, grey water or any other waste water suitable for reuse. Throughout this specification the word "comprise", or variations such as 20 "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a 25 context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application. 30 Summary of the Invention In accordance with one aspect of the invention there is provided a water supply system to selectively supplement with supplementing water a mains water supply for supplying water to predetermined water connections, the water supply system comprising: 35 demand means detecting a demand for water; 283224_1 4 status means detecting the presence of said supplementing water at or above a predetermined amount; delivery means to deliver said supplementing water; actuating means to actuate the delivery means in response to both detecting a 5 demand for water and the status means detecting the presence of said supplementing water at or above said predetermined amount; valve means blocking said mains water supply until said status means detects less than said predetermined amount; and a secondary water connection adapted to be supplied only said supplementing 10 water, wherein a one way valve is provided to prevent said mains water contributing to said supplementing water, and wherein the demand means includes a pressure switch or a flow sensor that provides a demand signal to the actuating means to provide an indication of the water demand. According to a further aspect of the invention there is provided an automated 15 method of selectively supplementing a mains water supply for supplying water to predetermined water connections comprising the steps of: detecting a demand for water; detecting the presence of supplementing water at or above a predetermined amount; 20 actuating delivery means to deliver supplementary water in response to detecting a demand for water and the status means detecting the presence of supplementing water at or above a predetermined minimum; blocking said mains water supply until the status means detects less than said predetermined minimum; and 25 supplying a secondary water connection with supplementing water only when such water is not less than said predetermined minimum. The demand means for detecting a demand for water may include a pressure switch or a flow sensor. The pressure switch or flow sensor will preferably provide a signal to a control unit to provide an indication of the water demand. 30 The status means may be any means suitable for detecting water or a water level in, for example, a storage tank or the like. One such status means may include a float valve mounted in a storage tank. Another status means may be a pressure switch or sensor measuring the pressure of water at or adjacent the bottom of a container which measure provides an indication of water depth and, therefore, quantity. However, 35 many other means for detecting the presence of water and/or a level of water are well 283224_1 5 known and any such detection or level sensing means may be used in the performance of the invention. The delivering means is preferably a pump associated with the supplementing water and able to deliver the supplementing water to satisfy the demand. The pump, in 5 a preferred form of the invention, is a submersible pump located within a water storage tank. However, the pump may be any suitable pump able to draw water from the storage tank, or other supplementing water supply. The actuating means preferably comprises a control unit which receives the demand signal and which also is adapted to receive a signal from the status means. In 10 response to the demand signal and the presence or absence of a status signal, the control unit actuates the pump. However, pump actuation only occurs if the signal, or absence of signal, from the status means provides an indication of the presence of supplementing water at or above a predetermined amount. The valve means preferably comprises a normally open solenoid valve in the 15 mains water supply line which is held in the closed position by a signal from the control unit until the status means detects less than said predetermined amount of water. Thus, the solenoid valve is normally held closed but is moved to the open position and is able to satisfy a demand from the mains supply in the event that a demand signal is received by the control unit but the status means indicates an 20 insufficient supply of supplementing water. In this case, the pump is not actuated. Further, in the event of a power failure, the solenoid valve will open to ensure a supply of water to the predetermined water connections. The demand may be caused by either a demand from the predetermined water connections or from the secondary water connection. In the event that the demand is 25 from the secondary water connection, such demand is only able to be satisfied if the presence or absence of a status signal causes the control unit to actuate the pump. In the event that the pump is actuated and, during operation, the water quantity falls below the predetermined minimum level, the status signal to the control unit will change state causing the pump to cease operating whereby the secondary water 30 connection will cease to receive water and the valve means will open so that any demand from the predetermined water connections is satisfied from the mains water supply. The system of preferred embodiments of the invention has a number of advantages including that pump operation is minimised, and control of the 35 supplementing water supply is effected only when sufficient supplementing water is available. More particularly, however, the secondary water connection, which may be 283224_1 6 a garden tap, will not be supplied with mains water thereby conserving the town water supply. In accordance with another aspect of the present invention there is provided a supplementing water supply system to selectively supplement with supplementing 5 water a mains water supply for supplying water to predetermined water connections comprising: demand means detecting a demand for water; status means detecting the presence of said supplementing water at or above a predetermined amount; 10 delivery means to deliver said supplementing water; actuating means to actuate the delivery means in response to detecting a demand for water and the status means detecting the presence of said supplementing water at or above said predetermined amount; normally open valve means adapted to be closed to block said mains water 15 supply when the status means detects said supplementing water at or above said predetermined amount; and a secondary water connection adapted to be supplied only supplementing water, wherein a one way valve is provided to prevent said mains water contributing to said supplementing water, and wherein the demand means includes a pressure switch or a 20 flow sensor that provides a demand signal to the actuating means to provide an indication of the water demand With this arrangement, the demand is met by the supplementing water until the status means detects the supplementing water to be less than said predetermined amount at which time the delivering means ceases delivering supplementing water, and 25 the valve means is caused to move to the normally open position whereby the predetermined water connections are supplied with mains water while the secondary water connection receives no water. This arrangement also ensures that, in the event of a power failure, the normally open solenoid valve allows mains water to supply any demand of the predetermined water connections. 30 In a variation of embodiments of the invention, the valve means comprises a normally closed solenoid valve in the mains water supply line. Such a normally closed valve is moved to the open position in the event that a demand signal is received by the control unit but the status means indicates an insufficient supply of supplementing water. In this case, the pump is not actuated. 35 According to a still further aspect of the invention there is provided a supplementing water supply system to supplement a mains water supply with 283224_1 7 supplementing water for supplying water to predetermined water connections comprising: a valve in said mains water supply to control the flow of mains water to a supply outlet connected to said predetermined water connections; 5 a supplementing water storage tank; a submersible pump in said tank connected to the supply outlet downstream of the valve; a pressure switch downstream of said pump and operable to provide an indication when water pressure downstream of said pump is less than a predetermined 10 value; a one-way valve downstream of said pump preventing water flow to the pump from the mains water supply; a secondary outlet connected to the pump upstream of the one-way valve to supply said supplementing water to a secondary connection; 15 supplementing water status means detecting when the amount of water in said tank is greater or less than a predetermined minimum; a control unit to control operation of said pump on receipt of a water demand indication from said pressure switch and when the status means detects water in the tank greater than said predetermined minimum; 20 said control unit causing actuation of said valve to admit mains water to the supply outlet and terminating pump operation when the status means detects water in the tank less than said predetermined minimum, wherein a one way valve is provided to prevent said mains water contributing to said supplementing water, and wherein the demand means includes a pressure switch or a flow sensor that provides a demand 25 signal to the actuating means to provide an indication of the water demand. In order that the invention is more readily understood, embodiment thereof will now be described with reference to the accompanying drawing. Description of the Drawings 30 Figure 1 schematically illustrates an embodiment of a water supply system in accordance with the invention; Figure 2 schematically illustrates the embodiment of Figure I showing one operating mode of the a water supply system; Figure 3 schematically illustrates a second operating mode of the system of 35 Figure 1; 283224_1 8 Figure 4 schematically illustrates a third operating mode of the system of Figure 1; and Figure 5 schematically illustrates a fourth operating mode of the system of Figure 1. 5 Description of the Preferred Embodiments The water supply system shown in Figure 1 includes a container, such as a storage tank 12, having an inlet 14. Supplementing water, such as rain water from a roof, or grey water, or other reusable waste water is supplied to the tank 12 through the 10 inlet 14. A simple float valve 16 is mounted in the tank 12 and is connected to a float valve switch 17 which is set to provide a status signal to an actuating means, in the form of a control unit 18, when the valve switch 17 is actuated. The status signal indicates that the amount of supplementing water in the tank 12 as detected by the float 15 valve 16 is at or above a predetermined amount. Alternatively, the signal may indicate that the amount of water is below said predetermined amount. A pressure switch or pressure sensor, being an alternate form of status means, may be fitted at or adjacent the bottom of the tank 12 to measure the pressure of water there and provide an indication of water depth and quantity of water. 20 In a further modification, the control unit 18 may poll the valve switch 17 to check its status, in a known manner. Alternatively, the float valve may be replaced by another form of water quantity sensing known in the art. A submersible delivery means, in the form of pump 19, is located in the storage tank 12. The pump 19, when operating, delivers water through the outlet pipe 21 to a 25 T-piece 22. Demand means, in the form of pressure switch 23, is mounted on the outlet pipe 21 and provides a demand signal to the control unit 18 when pressure in the outlet pipe 21 drops to a predetermined level, indicating a demand for water by a consumer. The T-piece 22 is connected to predetermined water connections through the consumer outlet 24 for supplying water toilets, washing machines and other non-drinking water 30 connections, while the other side of the T-piece 22 is connected to the mains supply 26 through a valve means in the form of a normally open, solenoid operated valve 27. If required by the governing water authority, a non-return valve 28 may also be provided in the mains water supply line 26. The non-return valve 28 may assist to prevent contamination of the mains water supply by preventing flow of water in a direction 35 towards the mains supply inlet. 283224_1 8a The normally open solenoid valve 27 is held in a closed position by a signal from the control unit. The outlet pipe 21 from the pump also connects to a secondary water connection or secondary consumer outlet 20, which may be a garden tap, lawn watering system or 5 similar outlet to which supplementing water may be supplied but which does not receive mains water. The outlet pipe 21 has a one-way valve 25 between the pump and the branch to the secondary consumer outlet 20 as well as a second one-way valve 31 between the branch to the secondary consumer outlet 20 and the T-piece 22. These one-way valves ensure that mains water cannot flow to the secondary consumer outlet 10 20 or to the pump. In operation, when a demand for water exists at either the consumer outlet 24, or the secondary consumer outlet 20, the pressure switch 23 will register the demand and signal the control unit 18 accordingly. The control unit 18, either being in receipt of a signal from the float valve switch 17, or interrogating that switch for its status, will 15 actuate the pump 19 if the float valve is in a position indicating supplementing water in the tank 12 above a predetermined level. The pump 19, therefore supplies 283224_1 9 supplementing water under pressure to satisfy the demand of the consumer outlet 24 and/or the secondary consumer outlet 20. The normally closed solenoid valve 27 remains held in the closed condition so that mains water from the supply 26 is not used to satisfy the consumer outlet demand. 5 This is schematically shown in Figure 2. When the demand of the consumer outlet 24 and/or the secondary consumer outlet 20 is satisfied, and there is sufficient supplementing water in the tank 12, pressure in the consumer outlet 24 increases thereby causing the pressure switch 23 to signal the control unit to cease operating the pump 19, if the pump has been operated to 10 satisfy the demand. If there is no supplementing water in the system, the valve 27 remains open. As shown in Figure 3, in the event that the float valve 16 indicates a level of water in the tank 12 below a predetermined minimum, the valve switch 17 provides the appropriate indication to the control unit 18 whereby the control unit 18 causes the 15 closed solenoid valve 27 to open to thereby satisfy the demand of the consumer outlet 24 from the mains supply 26. In this operating mode, the pump does not operate and the one-way valve 31 prevents mains water passing to the secondary consumer outlet 20 or to the pump 19. With the pump not operating, the secondary consumer outlet 20 cannot be supplied. 20 If desired, a pressure reducing valve (not shown) may be included in the mains supply line 26, such as between the non-return valve 28 and the solenoid valve 27. The operating mode shown in Figure 4 illustrates the flow of supplementing water when the pump operates to supply only the secondary consumer outlet demand, such as for watering a garden or the like. The solenoid valve 27 is maintained closed 25 by the control unit 18, and supplementing water is supplied only to the garden outlet. The operating mode of Figure 5 illustrates a power loss to the system.. In this mode, without power, the normally open solenoid valve is open to thereby connect the consumer outlet 24 directly to the mains supply 26. However, the one-way valve 31 prevents the mains water flowing to the garden outlet 20 or the pump. As soon as 30 power is restored, the solenoid valve is closed. In a further embodiment of the invention (not shown), the solenoid valve is a normally closed solenoid valve. With this arrangement, when a consumer demand is sensed, and the float valve 16 is in a position to indicate the presence of supplementing water in the tank 12 above the predetermined level, the control unit 18 initiates 35 operation of the pump 19 to supply the consumer demand, and the valve 27 remains closed. When the demand has been met, and the water pressure in the consumer outlet 188410_1.doc 10 24 increases, the pressure switch 23 signals the control unit 18 which shuts off the pump 19 If, however, insufficient water is available in the tank 12, instead of operating the pump 19, the control unit 18 causes the solenoid valve 27 to open to supply the demand from the mains supply.. 5 With this modified arrangement, a battery backup may be provided to open the solenoid valve 27 in the event of a power failure, so that water is supplied to the consumer outlet 24 from the mains supply 26. It will be appreciated that, during operation of the system in any of its embodiments, when the pump 19 is supplying demand, if the water level in the tank 10 drops to or below the predetermined level or amount, the control unit 18 will cause the solenoid valve 27 to open and shut down the pump operation so that a substantially seamless change to mains water supplying the demand of the consumer outlet occurs whilst stopping supply to the secondary consumer outlet 20. It will be appreciated by persons skilled in the art that numerous variations 15 and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. 188410_1.doc

Claims (27)

1. A water supply system to selectively supplement with supplementing water a mains water supply for supplying water to predetermined water connections, the water supply system comprising: 5 demand means detecting a demand for water; status means detecting the presence of said supplementing water at or above a predetermined amount; delivery means to deliver said supplementing water; actuating means to actuate the delivery means in response to both detecting a 10 demand for water and the status means detecting the presence of said supplementing water at or above said predetermined amount; valve means blocking said mains water supply until said status means detects less than said predetermined amount; and a secondary water connection adapted to be supplied only said supplementing 15 water, wherein a one way valve is provided to prevent said mains water contributing to said supplementing water, and wherein the demand means includes a pressure switch or a flow sensor that provides a demand signal to the actuating means to provide an indication of the water demand. 20

2. A water supply system according to claim 1 wherein the status means is suitable for detecting water or a water level in a container, such as a water storage tank.

3. A water supply system according to claim 2 wherein the status means includes a float valve mounted in the container. 25

4. A water supply system according to claim 2 wherein the status means is a pressure switch or sensor measuring the pressure of water at or adjacent the bottom of the container which measure provides an indication of water depth and quantity of water. 30

5. A water supply system according to any one of claims 2 to 4 wherein the delivery means is a pump associated with the supplementing water and able to deliver the supplementing water to satisfy the demand. 35

6. A water supply system according to claim 5 wherein the pump is a submersible pump located within a container, such as a water storage tank. 283224_1 12

7. A water supply system according to any one of claims 2 to 6 wherein the actuating means comprises a control unit which receives the demand signal and which also is adapted to receive a status signal from the status means. 5

8. A water supply system according to claim 7 wherein, in response to the demand signal and the presence or absence of the status signal, the control unit actuates the delivery means. 10

9. A water supply system according to claim 8 wherein actuation of the delivery means only occurs if the status signal, or absence of the status signal, from the status means provides an indication of the presence of supplementing water at or above the predetermined amount. 15

10. A water supply system according to any one of claim 7 to 9 wherein the valve means comprises a normally open solenoid valve in a mains water supply line which is held in the closed position by a control signal from the control unit until the status means detects less than said predetermined amount of water. 20

11. A water supply system according to claim 10 wherein, in the event of a power failure, the solenoid valve opens to ensure a supply of water from the mains water supply to the predetermined water connections.

12. A water supply system according to any one of claims 7 to I I wherein the 25 demand is caused by either a demand from the predetermined water connections or from the secondary water connection.

13. A water supply system according to claim 12 wherein, in the event that the demand is from the secondary water connection, such demand is only able to be 30 satisfied if the presence or absence of the status signal causes the control unit to actuate the delivery means.

14. A water supply system according to claim 12 or claim 13 such that in the event that the delivery means is actuated and, during operation, the supplementing water 35 quantity falls below the predetermined amount, the status signal to the control unit will change state causing the delivery means to cease operating whereby the secondary 283224_1 13 water connection will cease to receive water and the valve means will open so that any demand from the predetermined water connections is satisfied from the mains water supply. 5

15. An automated method of selectively supplementing a mains water supply for supplying water to predetermined water connections comprising the steps of: detecting a demand for water; detecting the presence of supplementing water at or above a predetermined amount; 10 actuating delivery means to deliver supplementing water in response to detecting a demand for water and detecting the presence of supplementing water at or above the predetermined amount; blocking said mains water supply until detection of less than said predetermined amount; and 15 supplying a secondary water connection with supplementing water only when the supplementing water is not less than said predetermined amount, wherein said mains water is prevented from contributing to said supplementing water.

16. A method according to claim 15 further comprising providing a demand signal 20 to provide an indication of the water demand to the actuating means.

17. A method according to claim 16 wherein the step of detecting the presence of supplementing water occurs at or adjacent the bottom of a container which detection provides an indication of water depth and quantity of water. 25

18. A method according to claim 17 wherein the step of actuating the delivery means only occurs if an indication of the presence of supplementing water at or above the predetermined amount is detected and provided. 30

19. A method according to claim 18 further comprising, in the event of a power failure, providing a supply of water from the mains water supply to the predetermined water connections.

20. A method according to any one of claims 15 to 19 wherein the demand is caused 35 by either a demand from the predetermined water connections or from the secondary water connection. 283224_1 14

21. A method according to claim 20 wherein, in the event that the demand is from the secondary water connection, such demand is only able to be satisfied if the detection of the presence or absence of supplementing water causes actuation of the 5 delivery means.

22. A method according to claim 21 further comprising in the event that the actuating step occurs and, during operation, the supplementing water quantity falls below the predetermined amount, the method further comprises ceasing actuation of the 10 delivery means whereby the secondary water connection will cease to receive water and enabling any demand from the predetermined water connections from the mains water supply.

23. A supplementing water supply system to selectively supplement with 15 supplementing water a mains water supply fgr supplying water to predetermined water connections comprising: demand means detecting a demand for water; status means detecting the presence of said supplementing water at or above a predetermined amount; 20 delivery means to deliver said supplementing water; actuating means to actuate the delivery means in response to detecting a demand for water and the status means detecting the presence of said supplementing water at or above said predetermined amount; normally open valve means adapted to be closed to block said mains water 25 supply when the status means detects said supplementing water at or above said predetermined amount; and a secondary water connection adapted to be supplied only supplementing water, wherein a one way valve is provided to prevent said mains water contributing to said supplementing water, and wherein the demand means includes a pressure switch or a 30 flow sensor that provides a demand signal to the actuating means to provide an indication of the water demand

24. A supplementing water supply system to supplement a mains water supply with supplementing water for supplying water to predetermined water connections 35 comprising: 283224_1 15 a valve in said mains water supply to control the flow of mains water to a supply outlet connected to said predetermined water connections; a supplementing water storage tank; a submersible pump in said tank connected to the supply outlet downstream of 5 the valve; a pressure switch downstream of said pump and operable to provide an indication when water pressure downstream of said pump is less than a predetermined value; a one-way valve downstream of said pump preventing water flow to the pump 10 from the mains water supply; a secondary outlet connected to the pump upstream of the one-way valve to supply said supplementing water to a secondary connection; supplementing water status means detecting when the amount of water in said tank is greater or less than a predetermined minimum; 15 a control unit to control operation of said pump on receipt of a water demand indication from said pressure switch and when the status means detects water in the tank greater than said predetermined minimum; said control unit causing actuation of said valve to admit mains water to the supply outlet and terminating pump operation when the status means detects water in 20 the tank less than said predetermined minimum, wherein a one way valve is provided to prevent said mains water contributing to said supplementing water, and wherein the demand means includes a pressure switch or a flow sensor that provides a demand signal to the actuating means to provide an indication of the water demand.

25 25. A water supply system substantially as hereinbefore described with reference to the accompanying drawings.

26. A supplementing water supply system substantially as hereinbefore described with reference to the accompanying drawings. 30

27. A method of selectively supplementing a mains water supply substantially as hereinbefore described with reference to the accompanying drawings. 283224_1