AU724021B3 - A self-cleaning filter system - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A PETTY PATENT Name of Applicant: Actual Inventor: Address for Service: Invention Title: MARK ANDREW DAWSON MARK ANDREW DAWSON CULLEN CO., Patent Trade Mark Attorneys, 239 George Street, Brisbane, Qld. 4000, Australia.

A SELF-CLEANING FILTER SYSTEM

I

The following statement is a full description of this invention including the best method of performing it known to me: 2 THIS INVENTION relates to a water filter system particularly relates to a specialty filter system which uses water flow to close a valve, to create a pressure pulse which will flush clean the filters used at the water intake. The self-cleaning filter system is therefore driven by the energy of water being drawn or sucked into a water intake, and through the mechanism.

Whether it be on a pump intake, a gravity feed line or anywhere water is being transferred from one place to another.

One of the main disadvantages of most types of filters is that they require regular servicing and cleaning. They can also restrict water flow as they become more blocked or fowled with debris, thus becoming less efficient. More often than not, the better or finer the filter is, the more cleaning and servicing it needs. The result of this in some cases is that filters in water transfer are not used. This may cause damage or down time to pumps, blockages or damage to pipelines, and of course, the delivery of dirty water.

A self-cleaning filter system which is the subject of the present invention uses a principal which is known. Utilising the effect known as a water hammer, this filter system allows water to flow through a filter and into a flow chamber provided with a valve which can be moved to the closed position by water flow. Such a valve being biased or balanced to open again, by way of a spring or adjacent valve. The closing of the valve creates a pressure pulse (water hammer) on the intake side of the valve. The pressure pulse provides a backward flow of water through the filter and it momentarily cleans away debris or particles which have been sucked onto it. Once the pressure pulse has been exhausted, the valve is encouraged to open, by way of its biased spring or adjacent valve. Upon opening, water is once again, able to flow through the valve and the process is repeated.

The disadvantages of not having a filter cleaning system are obvious, and in most cases of water transfer, whether it be by way of pump or gravity feed, sooner or later the result is blocked or restricted filters. This would occur more often with fine or small micron filters, such as the type used for filtering out fine particles or bacteria and biological organisms.

There are many disadvantages with known filter cleaning mechanisms and systems.

One disadvantage is that some known filter cleaning systems require electricity at the water intake site and are often complicated electronically controlled devices. This makes them unsuitable for isolated or inexcessible areas.

Other types must be manually activated or manually back flushed by reversing or changing the direction of the filters.

In other cases of filter cleaning systems, the disadvantages are that filters must be positioned out of the water and placed in a convenient spot for cleaning and servicing. Thus, pumps or pipelines before (upstream) the filters could become damaged or blocked by unfiltered water, fowled with debris.

The present invention is directed at a self-cleaning filter system of the type which uses water flow to close a biased valve, which creates a back flush, which in turn cleans the filter on the intake side of the mentioned valve.

This self cleaning filter system may overcome at least some of the above mentioned disadvantages and may offer the public a useful alternative to known commercially available units.

According to a first broad form there is provided a filter cleaner having a fluid flow chamber which in use is in fluid communication with a filter, the chamber having an inlet, an outlet, a valve downstream from the filter, the valve being moveable between a closed and an open position and is moved to the closed position by a flow of fluid between the inlet and the outlet and means to move the valve to the open position and when the valve has been moved to the closed position by a flow of fluid, a backward flow of fluid towards the filter is created.

The invention resides in a self cleaning filter system which uses water flow to close valves and create a pressure pulse to clean filters. The mechanism could be shaped in a T configuration, with 2 water intakes, upon which filters of an undetermined size, would be fitted opposite to each other, in between and communicating among each, a flow chamber encompassing 2 valves, and corresponding threaded holes, positioned between intake and valve, allowing for the mounting of diaphragm assisted air tanks, said valves situated oppositely opposed to each other, downstream of the filters and air tanks and biased against each other by way of an attached rod, such attached rod being the means by which each valve is moved between open, the valves being positioned each side of, and communicating with a non-return valve of corresponding size to the flow chamber, the non-return valve being downstream of the filters, tanks and biased valves and communicating with a water outlet through which a clean unrestricted water flow may be drawn.

The self-cleaning filter system described herein has a number of advantages. Firstly, the unit is a water powered mechanism, requiring no additional power source other than the water being drawn through the mechanism.

The mechanism automatically cleans filters from the inside, thereby reducing required maintenance.

The self-cleaning filter system is compact and light-weight, allowing it to be more readily transported to, or positioned on site.

The self-cleaning filter system could be made from corrosion free, friction modified, light weight materials such as polypropylene, polythene, PVC plastic or some other suitable substance. The use of such materials would ensure long life of the unit, and good flow throughout the mechanism.

One advantage with the self-cleaning filter system is the ability to use a variety of different types of filters.

Another advantage of the invention herein, is the ability to add to the mechanism, an additional filter cleaning, pressure pulse, by way of a diaphragm assisted air tank. The diaphragm assisted air tank, communicating with the flow chamber, downstream of the filter, upstream of the valve, will create a pressure pulse of its own when activated by the pressure pulse caused by the valve closing. This in turn gives the system a greater filter cleaning ability.

The valves present in the self-cleaning filter system may be poppet valves which are preferably removable, and preferably have replaceable o-rings which should be made from some type of resilient rubber or some other type of suitable substance.

TAny springs or rods present in the said invention should be 0-V stainless steel or some other corrosion resistant substance.

In a different embodiment of the invention, perhaps using suitable components for such, the system could be applied to air filtration.

In another embodiment of the invention, water passes through a water intake filter, down a gravity feed pipeline which is connected to a selfcleaning filter mechanism, the mechanism consists of a flow chamber, encompassing a sinrgle valve which may be moved between the closed position preventing water from flowing through, the flow chamber may communicate with a diaphragm assisted air tank, upstream of the valve, the chamber being provided with a water baffle on the discharge, the baffle is preferably operatively associated with a means to move the valve between its opened position.

The means may be in the form of an adjustable spring biased rod. The baffle can house the adjustable spring biased rod and may be fitted together and can be easily removed from the discharge end of the mechanism to allow for adjustments to be made.

Embodiments of the invention will be described with reference to the following drawings in which Figure 1 is a cross-section plan view of a self-cleaning filter system according to an embodiment of the invention.

Figure 2 is a cross-section view of the adjacent valves in the flow chamber and the attaching rod between the valves, of the mechanism of Figure 1.

Figure 3 is a cross-section view of a self-cleaning filter system according to an alternative embodiment of the invention.

Figure 4 is a cross-section view of the flow chamber, valve, spring biased rod, and baffle, of the mechanism of Figure 3.

Referring to the drawings and initially to Figure 1, here is shown a self-cleaning filter system 11 which uses water flow to move valves between the closed position to create a backward pressure pulse to clean filters. The basic components of mechanism 11 are, water inlets 12 and 13, to which a variety of different types of filters may be fitted, communicating in between and among said intakes a flow chamber 14, encompassing valves 15 and 16 and communicating with diaphragm assisted air tanks 17 and 18 which are positioned downstream of said intakes 12 and 13, and upstream of said valves 15 and 16, such valves being opposite to, and biased against each other and with the means to move each other between open and closed position, the means being an attaching rod 19, said valves 15 and 16 communicating with, and positioned either side of and upstream of, a nonreturn valve 20, said valve 20 with a means to be moved between the open position as drawn water flows through, is communicating with the discharge outlet 21, through which a filtered non-restricted flow of water may be drawn.

Finally, the self-cleaning filter system according to the embodiment has a means to move oppositely opposing valves 15 and 16 to their alternating, open position and this is in the form of an attached rod 19, positioned in between, and connected to, said valves 15 and 16.

Referring to the various components in greater detail, selfcleaning filter system 11 is made from light-weight, robust, friction-modified materials with the various components being threadably coupled together to allow for maintenance, repair or inspection. The mechanism 11 is placed relative to water, whereby the water is drawn through a filter of undetermined size which is connected to an inlet 12 and into the flow chamber 14. In the initial stage of operation, valve 15 could be naturally biased to its open position, allowing water to be drawn through such valve, through the nonreturn valve 20, and out through the discharge 21. As water flows through intake 12, into chamber 14 and past valve 15, valve 15 is moved to its closed position where it seals against valve seat 22 to prevent the flow from continuing. This causes a pressure pulse, backwards from valve 15, through that section of chamber 14 and backwards through any filter connected to intake 12.

The efficiency of the self-cleaning filter system is enhanced with the addition of a flexible diaphragm 24 inside air tank 18, situated downstream of intake 12, upstream of valve 15 and communicating with the associated section of chamber 14. The pressure pulse caused by the closing of valve also forces diaphragm 24 upwardly and this results in a compression of the air behind the diaphragm and as such results in a kick back or pressure pulse, which flows backwardly through the associated section of chamber 14 and backwardly through the filter connected to intake 12. As soon as valve 15 is moved to the closed position by water flow, it forces its biased, oppositely opposed valve, valve 16, to move to its open position. The means to move such valve is by way of an attached or connecting rod 19. Water is now drawn through filter intake 13, into the associated section of chamber 14, past valve 16, through the non-return valve 20 and out the discharge 21. As water flows past biased valve 16 it causes it to be moved to the closed position and into engagement with valve seat 23. A backwardly moving pressure pulse is now created in the associated section of chamber 14, resulting in the flushing of the filter mounted or connected to intake 13 and the compression of air behind diaphragm 25 in air tank 17, which in turn creates an additional backwardly flowing pressure pulse. As valve 16 closes, it has the means to force valve 15 open again. The means being attached rod 19. Once valve is moved to the open position, water is drawn through inlet 12 and the whole process is repeated.

By alternating water flow between two intakes, a continual unrestricted flow of filtered water may be drawn. The section of the T configured flow chamber 14, shown in Figure 2 (and Figure 1) encompasses two oppositely opposing valves 15 and 16, biased to move each other between open. The means to move said valves is by way of an attached rod 19, which is removable and made from stainless steel or some other suitable material. Mentioned rod 19, joins or connects valve 15 to valve 16 and in doing so biases such valves against each other. The valves 15 and 16, are of the poppet type, and are equipped with o-rings 26 and 27, to ensure a good seal when alternately engaged in valve seats 22 and 23. Between said valves, downstream of, and communicating with, a non-return valve 20. Valve with the means to be moved between open. Such a means being the flow R"Aof water drawn through the valve and out through the discharge 21.

Figure 3 illustrates a second embodiment of the invention which uses the exact same principal to clean a filter at the water intake, and as such, like numbers have been used to illustrate like components.

It should be appreciated that the embodiment in Figure 3 is more suited to gravity feed or syphon type water transfer, due to the restriction of water flow, caused by its single valve operation.

Water is drawn through a filter, down a pipeline and through a self-cleaning filter system, position downstream at the outlet end of such a pipeline. The self-cleaning filter system 11, comprises of a water intake 12, in communication with a flow chamber 14, encompassing a valve 15 which has the means to be moved between the closed position whereby it engages with its valve seat 22 and spring biased rod 19. The means to move said valve to the closed position is by way of water flow, and the means to be moved between open, by way of an adjustable spring biased rod 19, free running in a bush 28, mounted in a removable strainer type housing 29, at the discharge 21. The rod 19 could be threaded along two thirds of its length to allow for adjustments and should have a hexagonal head at one end to assist in such adjustments. Such a rod, its lock nuts and spring should be made from stainless steel or some other type of hard wearing non-corrosive substance, and should have a bush 28 made from brass or some other appropriate substance. The valve 15 should be of the poppet type and could be equipped with an o-ring 26 to ensure a good seal when engaged with valve seat 22.

The backwardly flowing pulse, cleans a filter positioned at the intake. Such a pulse is caused when water flow moves valve 15 to the closed position. The valve and therefore the pulse, may be adjusted by way of the operatively associated spring biased rod 19. Such a rod could be housed in an easily removed strainer or baffle 27, which is downstream of and communicating with the discharge 21. Such adjustments allow the mechanism 11, to operate from a variety of head heights and flow variations.

Showing an embodiment of the invention as described in Figure 3, Figure 4 gives greater detail to the chamber 14, the valve 15 and the removable baffle 27, which houses the spring biased rod 19.

9 It should be appreciated that various changes or modifications may be made to the embodiment without departing from the scope and spirit of the invention as claimed herein.

Claims (4)

1. A filter cleaner having a fluid flow chamber having an inlet and an outlet and which in use is in fluid communication with a filter located upstream therefrom, the chamber having an inlet, an outlet, a valve downstream from the filter, the valve being moveable between a closed and an open position and is moved to the closed position by a flow of fluid between the inlet and the outlet and means to move the valve to the open position and when the valve has been moved to the closed position by a flow of fluid, a backward flow of fluid towards the filter is created.

2. The cleaner of claim 1, which further includes an air chamber communicating with the fluid flow chamber intermediate the valve and the filter.

3. The cleaner of claim 1, substantially as hereinbefore described with reference to Figures 1 and 2 or Figures 3 and

4. DATED this 14h day of July 2000 Mark Andrew DAWSON By his Patent Attorneys CULLEN CO.