BACKGROUND OF THE INVENTION

Water shortages, whether caused by drought or increased water usage, are common in many countries. The need for devices which reduce water and energy consumption is manifest.

There have been numerous proposed constructions of shower water saving devices designed to restrict the amount of water used in showers. These devices are commonly referred to as 'flow regulators' and reduce and concentrate the flow of water through the shower rose per unit of time. A principal disadvantage of these devices is that they do not restrict the overall time each user spends in the shower. Another disadvantage of these devices is that they do not allow an adequate flow of water for the user to enjoy a satisfying shower. This invention is designed to provide a more user-friendly way of restricting water usage in the shower. It primarily restricts the amount of time the user can spend in the shower without restricting the natural flow of the water. However, it can be used in conjunction with 'flow regulators'.

Given the prevalent need for water restrictions in many countries, the device will assist: (i) governments to ensure that water restrictions are complied with; and (ii) residential home owners and occupants to comply with government imposed water restrictions.

The invention will benefit residential home users, especially parents who become aggrieved by the amount of time their children spend in the shower without concern for the amount of water, energy and money they are dissipating.

The invention will also provide particular benefit to people who own venues where showers are used by clientele or the public. Such venues include hotels, motels, gymnasiums, clubs, youth hostels, hostels for tourists, and natural resource departments. The invention will enable such organisations, as well as the average household user, to save money on water and gas/electricity consumption.

Since the device can be activated by push-button, it will also assist people who have difficulty turning taps due to manual dexterity disabilities, such as arthritis. PRIOR ART - RESULTS FROM INTERNATIONAL SEARCH REPORT

From having obtained an international search report, the inventor/applicant is aware of the following patents:

1. US 4,921 ,209 A (MOINEAU) 1 May 1990 2. US 4,867,189 A (MOINEAU) 19 September 1989 3. DE 203 02 724 Ul (TOURIST CONCEPT GMBH) 18 June 2003

We note that the third patent has been granted in Germany and has not been translated into English.

The content of the first and second and patents are to a large extent a replica of one another and otherwise the same in substance. As such, we refer to the second and third patents as the "US Patent".

The differences between the present invention and the US Patent are set out below:

Difference 1 : The US Patent uses two mechanical timers (which are like clocks or garden timers). The present invention does not use mechanical timers, because this function can be programmed into the programmable logic controller (PLC) (6). The function of the LCD Panel (7) in the present invention is only to show the time remaining for which the PLC (6) has been programmed to allow the water to flow through the solenoid valve (4).

Difference 2: The US Patent uses physical relay boards to operate its solenoids whereas the present invention does not use such relays.

Difference 3: The present invention uses a proprietary solenoid valve (4) to control water flow, which can be sourced from many manufacturers. The US Patent, on the contrary, is built exclusively around the "one off purpose-built valve with dual solenoids. Therefore, the US Patent could not work without a major change to the operating system.

Difference 4: The present invention consists of an all solid state control (i.e. the PLC) (6) and relies on its functions taking place through the commands received from an integrated circuit, whereas the US Patent relies on numerous relays and timers to carry out its functions.

Difference 5: The present invention offers the user the option of being able to change the duration for which water is allowed to flow through the solenoid valve (4). By using a key in the override keyhole (8), the user can select between four programs which are programmed into the PLC (6). The four programs allow water to flow through the solenoid valve (4) for periods of 3 minutes, 5 minutes, 7 minutes (or for a specific period as otherwise programmed) or without time restriction.

In the case of the US Patent, it appears that the period of water use is predetermined and fixed at the time of manufacture. As such, if the period of water use was to be changed, it would require a technician to carry out the change.

Difference 6: The present invention uses a visible LCD panel (7) to show the amount of time remaining by way of a digital clock countdown, whereas the US Patent uses an alarm bell to provide an audible warning shortly before the flow of water is to cease.

Difference 7: The dimensions of the present invention are 152 x 74 x 44.5 (H x W x D - in mm). It is estimated that the dimensions of the US Patent would be approximately 450 x 180 x 200.

Difference 8: The present invention will cost between $50-$60 to manufacture. It is estimated that the US Patent would cost between $250-$500 to manufacture.

Difference 9: The present invention is designed so it can be installed between a standard shower wall mounting (i.e. a Vz inch BSP male nipple) and a shower arm connection (i.e. a Vz inch BSP female nipple) (15) - refer to Figure 3. However, the US Patent does not claim this and appears to be too bulky to allow it to be possible. BRIEF DESCRIPTION OF INVENTION

This invention relates to a shower water saving device which is primarily operated by a programmable logic controller (6) ("PLC") which is programmed to allow water to flow through a steam rated solenoid valve (4) for a programmed period of time. When the solenoid valve (4) is not energised, the plunger in the valve body of the solenoid valve (4) remains blocked and thus does not allow water to flow through the valve body.

The device is designed so it can be sold as a complete unit and is easy to install between a standard shower wall mounting (i.e. a 1A inch BSP male nipple) and a shower arm connection (i.e. a 1A inch BSP female nipple) (15). Due to the minimal number of parts used, the invention can be manufactured and sold at an affordable retail price and installed by an average handyman without the need of a plumber.

It is envisaged that the device will be sold with fixed time limits of either three, four or five minutes. The flow of water is activated by a push-button (9) which when pressed allows the shower to flow for the programmed amount of time. After the time limit has been reached and the flow of water has ceased, the PLC (6) is programmed to disallow the reset button (9) to energise the solenoid valve (4) for a specific period of time (it is envisaged that a suitable period of time would be approximately 2 minutes). This feature acts as a disincentive for users who seek to continue their shower after the programmed time has lapsed. The device is also designed so water cannot flow through the valve body of the solenoid valve (4) if a cunning user removes the 12 volt battery pack (11).

The settings of the device can be altered by inserting and turning a master key in the override keyhole (8), which allows for four different program options. The four programs allow water to flow through the solenoid valve (4) for a period of 3 minutes, 5 minutes, 7 minutes (or for a specific period as otherwise programmed) or without time restriction. The flow of water without restriction is achieved by the PLC (6) being programmed to allow the solenoid valve (4) to remain permanently energised. This allows the device to be flexible for its users, which will include business proprietors, staff members and home users.

When the solenoid valve (4) is energised, the amount of time for which it will remain energised (and permit the flow of water through the valve body) is displayed on the LCD panel (7). This allows the user to adequately prepare for the end of their shower. BRIEF DESCRIPTION OF THE DRAWINGS

FIGURE 1 is a perspective view of the present invention; FIGURE 2 is a front view of the present invention; FIGURE 3 is a side view of the present invention; FIGURE 4 is the plan view (or aerial view) of the present invention.

All figures contain number references which correspond to the same parts. DETAILED DESCRIPTION OF THE INVENTION

It is the principal object of the present invention to create a complete device which is easy to install between a shower wall mounting and a shower fitting (15) to provide a time limitation on the flow of water through the shower rose per user. It comprises well-known devices of prior art, the most notable being a solenoid valve (4), a PLC (6) and a Liquid Crystal Display panel ("LCD panel") (7).

Solenoid valves are well known devices used to control the flow of fluid. They consist essentially of a valve body comprising inlets and outlets for the flow of fluid and a wire coil with a moveable plunger that sits against the wire coil. When current is applied to the wire coil, an actuating magnetic field is created which acts upon the plunger whose resulting motion actuates the valve. _ Another specific characteristic of solenoid valves is whether the valve body is open or closed when, the wire coil (5) is not energised. The valve body of the solenoid valve (4) used for this invention must be closed when it is not energised, so that when the wire coil is energised water flows through the valve body and when it is not energised (and if the battery pack (11) is removed) the flow of water is blocked.

The type of solenoid valve (4) used must be (i) steam rated to allow for the flow of hot water through the valve body, (ii) able to allow 4 bar in water pressure and (iii) small enough to allow it to fit within the moulded housing cover (10).

PLCs (6) and LCD panels (or LED Timers) (7) are both well known devices of prior art and there is no need to explain the functionality of these devices in this specification. " Suffice to say that a PLC: (i) is an electronic device generally run on a low voltage charge; (ii) designed to initiate a signal either on being switched on or when it receives a signal from some other external device; (iii) has a series of input signals and a series of output signals which can vary from a few to a hundred; and (iv) can be programmed to perform a series of functions. A standard PLC is required for this invention (i.e. one which could be used for all other functions from switching on a pizza oven to starting up a pump).

Shower wall mountings commonly consist of Vi inch British Standard Pipe ("BSP") male nipples (otherwise known as BSP male-thread nipples), to which shower fittings (15) are connected. This invention connects to the shower wall mounting by way of a 1A inch BSP female nipple (1). The inlet of the valve body of the solenoid valve (4) is connected to the 1A inch BSP female nipple (1) and the outlet of the valve body is connected to a 1A inch BSP male nipple (14). The most suitable invention. The shower fitting (15) connects to the Vi inch BSP male nipple (14) in the same way it would connect to the shower wall mounting if this invention was not installed.

A wire coil (5) is a standard feature inside a solenoid valve (4) and this is the means for providing an electric current to make the plunger inside the wire coil (5) move downward to allow the flow of the water through the valve body of the solenoid valve (4). When the solenoid valve (4) is not energised (i.e. when electricity is not fed to the wire coil (5)), the plunger inside the solenoid valve (4) remains in a position so as to completely block the flow of water through the valve body. The electrical current which feds the wire coil (5) comes from the PLC (6) which is connected to the 12 volt battery pack (11). If the battery pack (11) is removed, the Solenoid valve (4) cannot be energised and the valve body of the solenoid valve (4) remains blocked (note - if any users remove the 12 volt battery pack then the flow of water through the valve body will remain blocked).

The PLC (6) is connected to the following parts by way of hard- wiring: • solenoid valve (4) • LCD panel (7) • reset button (9) • override keyhole (8) • 12 volt battery pack (11)

The PLC (6) is powered by a 12 volt battery pack (11) and is programmed to, upon the pressing of the reset button (9), make the solenoid valve (4) allow the flow of the water through the valve body of the solenoid valve (4) for a specific amount of time.

The 12 volt battery pack (11) has a removable panel (12) on the bottom of the housing cover (10) held in place by a fixing screw (13). The panel is removable to allow the batteries (11) to be changed when required. When in place the removable panel (12) must adequately mate with the housing cover (10) so as to prevent moisture entering the device and affecting the electrical circuits.

The PLC (6) is programmed to allow the following: • whenever the reset button (9) is pressed (except as set out below) to energise the wire coil (5) inside the solenoid valve (4) and thus make the plunger unblock the valve body of the solenoid valve (4) for a specific amount of time ("the time period"), so as to allow water to flow through it during this time. • the wire. coil (5) inside the solenoid valve (4) to not be energised for an appropriate duration of time directly after it has been previously energised. • the time period to be 3 minutes, 5 minutes, 7 minutes or indefinite as selected by way of the override keyhole. For the latter, the PLC (6) is programmed to allow the wire coil (5) inside the solenoid valve (4) to remain energised and therefore allow water to flow through the valve body of the solenoid valve (4) without restriction. The override keyhole (8) is to be locked by way of a circular key, or another type of suitable key, which makes it difficult to pick the lock. • to display on the LCD panel (7) the amount of time remaining for which water will flow through the valve body of the solenoid valve (4).

It is envisaged that when the present invention is manufactured the PLC (6) will be replaced by a standard microchip and that the PLC (6) will be used to program each microchip. The reason for this is that a microchip is less expensive than a PLC (6), yet just as effective as a PLC (6) with regard to this invention.

A rubber gasket (3) is used to prevent fluid leaks between the two mating surfaces of the moulded backing plate (2) and the moulded housing cover (10). The moulded backing plate (2) and the moulded housing cover (10) must be made out of water protective materials, such as high density propylene (HDPE) or zinc casting, to prevent water affecting the materials they are designed to cover.

Drawings are enclosed to assist with the understanding the invention.