FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
/. Title of the invention
A WATER FILTER
2. Applicants)
Name Nationality Address
TATA CHEMICALS LTD. INDIA BOMBAY HOUSE, 24 HOMI MODI STREET MUMBA1-40000!
TATA CONSULTANCY SERVICES LTD. INDIA TCS HOUSE, RAVELINE STREET, 21 DS MARG, FORT MUMBAI MUMBA1-40000I

3. Preamble to the description
COMPLETE SPECIFIC A TION
The following specification particularly describes the invention and the manner in which it is
to be performed.

The invention relates to the treatment of water. More particularly the invention relates to a water filter.
DESCRIPTION OF RELATED ART
Clean potable water is a basic human requirement. However, a large portion of the world's population, especially those living in developing counties do not have access to clean potable water.
Growing population, lack of sanitary conditions, poverty, poor planning, industrial pollution, over exploitation of natural water and national disasters are the main reasons of contamination of water.. This contaminated water is the source of many diseases such as diarrhea, dysentery, fever, abdominal pain, and constipation, caused due to bacterial contamination transmitted through water. In India for example, as per the data collected by the Ministry of Health and Family Welfare, in 2003 there were 10.5 million cases of diarrhea with 4709 deaths resulting majorly due to consumption of contaminated water. According to the World Health Organization, the provision of safe water alone can reduce diarrheal and enteric disease by up to 50%, even in the absence of improved sanitation and other hygiene measures.
Many water purification devices like in-line (electricity operated) devices, terminal end devices including counter top and faucet mounted filtration and self-contained batch system including gravity fed systems have been introduced into the market. However, many communities of the developing countries do not have access to piped water therefore they are unable to make use of inline purification units. Moreover, the people in these communities cannot afford the point-of-use water purifiers currently available in the market. The maintenance requirements and the high cost of consumables of these purifiers pose further hurdles for the adoption of these devices. In addition the water that is available to these communities has a large amount of solid particulate matter present in it that may result in the
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clogging of the point of use purifiers that may decrease both the efficiency and the life of the purifier that adds to the cost of using these purifiers.
Therefore there is a need for an economical water filter that can remove the suspended particulate matter present in the water. More particularly the water filter should be adapted for-a water storage vessel. SUMMARY
The invention relates to a filter for a water storage vessel, the water storage vessel including an inlet, the filter comprising an adaptor having a hollow body extending between a first and second end, the adaptor having an opening at the first and second end for allowing the flow of water through the adaptor; the first end sized smaller than the inlet of the storage vessel and the second end sized larger than the inlet of the storage vessel; in that the adaptor may be retained by the water storage vessel at the inlet; and a filter bag open at one end, the open end of the filter bag detachably coupled to the first end of the adaptor, the filter bag covering the opening of the adaptor at the first end. The adaptor is preferably made of food grade plastic and the filter bag is preferably made of fine pore material. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
The accompanying drawing illustrates the preferred embodiments of the invention and together with the following detailed description serves to explain the principles of the invention.
FIG 1 illustrates an isometric view of a filter in assembly in accordance with an embodiment. FIG 2 illustrates a sectional view of a filter in assembly in accordance with an embodiment. FIG 3 illustrates a front view of an adaptor in accordance with an embodiment. FIG 4 illustrates an isometric view of an adaptor in accordance with an embodiment. FIG 5 illustrates a sectional view of an adaptor in accordance with an embodiment. FIG 6 illustrates an isometric view of an adaptor in accordance with an alternate embodiment.
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FIG 7 illustrates a front view of a filter bag in accordance with an embodiment. FIG 8 illustrates an isometric view of a filter bag in accordance with an embodiment. FIG 9 illustrates an embodiment of the mechanism for coupling the filter bag to the adaptor. DETAILED DESCRIPTION
To promote an understanding of the principles of the invention, reference will be made to the embodiment and specific language will be used to describe the same. It will nevertheless be understood that no limitation of scope of the invention is thereby intended, such alterations and further modifications in the illustrated system and such further applications of the principles of the inventions as disclosed therein being contemplated as would normally occur to one skilled in art to which the invention relates.
A water filter is described. More particularly a water filter for a water storage vessel is described. The water filter is configured such that it can be used on different water storage vessels having inlets of different sizes.
With reference to the accompanying figures and initially to figures 1 and 2 a water filter (10) in accordance with an embodiment is illustrated. The water filter includes an adaptor (20) for retaining the filter to a water storage vessel and a filter bag (30) detachably coupled to the adaptor. The filter is placed at the inlet or mouth of a storage vessel as illustrated in figure 2. The filter is placed such that at least some portion of the adaptor (20) is retained at the inlet (60) of the storage vessel while remaining portion of the adaptor along with the filter bag (30) extends down into the storage vessel. Water entering the storage vessel is guided by the adaptor into the filter bag where particulate matter is retained.
Figures 3, 4 and 5 illustrate the adaptor (20) of the water filter in accordance with an embodiment. The adaptor has a hollow main body (21) extending between a first end (40) and a second end (50) of the adaptor. The first end (40) has an opening (41) and the second end (50) has an opening (51) for allowing the flow of water through the adaptor. In
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accordance with an aspect the first end (40) of the adaptor is sized smaller than the inlet of the storage vessel and the second end (50) of the adaptor is sized larger than the inlet of the storage vessel such that adaptor is retained by the storage vessel at its inlet while the first end (40) extends down into the storage vessel. The main body of the adaptor may have any shape including but not limited to cylindrical or conical and preferably the main body has a conical shape.
In accordance with an embodiment the second end (50) of the adaptor has at least one extension configured for retaining the filter to the inlet of the water storage vessel. In the illustrated embodiment the extension (23) is in the form of a ledge present around the periphery of the second end (50) of the adaptor. In the illustrated embodiment a peripheral lip (24) extends downwards from the ledge such that when the filter is put on the storage vessel the ledge may overlap with the edge of the inlet of the storage vessel. In accordance with an embodiment the extension is in the form of a flat plate (23) that extends on at least one side of the adaptor. In the embodiment illustrated in figure 6 the plate extends around the periphery of the second end (50). The second end, or the body between the first end and the second end of the adaptor allows the filter to be retained by a number of storage vessels having inlet of different sizes, therefore allowing the filter to be used for a wide variety of storage vessels.
Figures 7 and 8 illustrate an embodiment of the filter bag (30). The filter bag has a main body (31) with an opening (32) at one end. The main body (30) of the filter bag may be of any shape including but not limited to cylindrical or conical. The main body (31) in the illustrated embodiment is a hollow cup shaped cylinder having a closed end (36) and an opening (32).
The filter bag may be made of fine porous material capable of removing floating debris and particulate matter from water. In accordance with an aspect the filter bag is made
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of non woven sandwiched material including but not limited to cotton cloth, canvas, melt blown polypropylene fabric, melt blown polyester fabric, spun bound woven fabric, spun bound non-woven fabric, needle punched polyester fabric, needle punched polypropylene fabric, mix of spun or melt blown fabric and preferably the filter bag is made of non woven needle punched polypropylene fabric.
In accordance with an aspect the filter bag is adapted to be detachably coupled to the first end of the adaptor such that the filter bag covers the opening (41) of the first end of the adaptor. This allows the filter bag to be removed from the adaptor with ease for washing or cleaning and removal of retained particulate matter. Moreover the filter bag can be replaced without the need to replace the entire filter.
Figure 9 illustrates an embodiment of the mechanism for coupling the filter bag to the adaptor. In the embodiment illustrated, a coupler (33) is present at the opening (32) of the filter bag. A holder (22), is present at the first end (40) of the adaptor for coupling with the coupler (33) of the filter bag. The coupler may be coupled to the holder by any means including but not limited to threads, snap fit or a notch joint. In the embodiment illustrated the coupler (33) on the filter bag is in the form of ring (34) that is attached to the main body (31) of the filter bag at the opening (32). The ring (34) has a projection (35) configured for fitting into a slot (25) on the first end (40) of the adaptor. The slot (25) is formed between a collar (26) present at edge of the first end (40) of the adaptor and a projection (27) present at the inner surface of the opening (41).
In accordance with an aspect the coupler is made of food grade plastic. In accordance with an aspect the ring (34) may be attached to the filter bag by any means including but not limited to heat sealing, ultrasonic sealing or by moulding and preferably the ring should be attached to the filter bag by moulding.
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To assemble the filter (10), the filter bag (30) is placed inside the adaptor (20) such that the projection (35) of the filter bag snap fits into the slot (25) of the adaptor to form a mostly leak proof joint.
To filter water, the entire filter is placed at the inlet of a storage vessel such that the adaptor is retained by the inlet of the storage vessel, and its first end along with the attached filter bag extends down into the storage vessel. Water is then poured though the opening (51) such that is flows through the opening (41) into the filter bag. The filter bag retains particulate matter and other impurities. The filtered water then flows thought the filter bag into the storage vessel. In accordance with an aspect the turbidity of water exiting out of the filter should be reduced by at least 20% on the nephelometric turbidity units (NTU) scale.
In accordance with an aspect the adaptor is sized corresponding to average sizes of inlets of commonly used storage vessels. In accordance with an aspect the preferred diameter of the opening (50) of the adaptor body should be between 50 to 500 mm and preferably the opening diameter of the adaptor is 200mm. In accordance with an aspect the preferred diameter of the opening (40) of the adaptor body should be between 10 to 500 mm and preferably the diameter of the adaptor is 100mm. In accordance with an aspect the distance between the first end and the second end of the adaptor should be between 20 to 300mm and preferably the distance should be 80mm. In accordance with an embodiment the adaptor is made of food grade plastic.
In accordance with an aspect the thickness of the fabric may be between 0.1mm to 20 mm and preferably the thickness of the fabric should be 1.9 mm. In accordance with an aspect the pore size of the filter bag should be between 0.2 to 50 micrometers and preferably the pore size of the filter bag is 5 micrometers. In accordance with an aspect the length of the filter bag should be made such that the flow rate of should be between 0.1 and 100 liters per minute and preferably the flow rate of the filter bag should be 10 litres per minute. In.
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accordance with an aspect the length of the filter bag may be between 0 to 300 mm and preferably the length of the filter bag is 100 mm.
The filter as described by this document is a simple and effective point of use water filter that can remove particulate matter from water. Moreover the water filter may be attached to any water storage vessel.
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We claim:
1. A filter for a water storage vessel, the water storage vessel including an inlet, the filter
comprising:
an adaptor having a hollow body extending between a first and second end, the adaptor having an opening at the first and second end for allowing the flow of water through the adaptor; the first end sized smaller than the inlet of the storage vessel and the second end sized larger than the inlet of the storage vessel; in that the adaptor may be retained by the water storage vessel at the inlet; and a filter bag open at one end, the open end of the filter bag detachably coupled to the first end of the adaptor, the filter bag covering the opening of the adaptor at the first end.
2. A filter as claimed in claim 1 wherein the adaptor is conical.
3. A filter as claimed in claim 1 wherein the adaptor is cylindrical.
4. A filter as claimed in claim 1 wherein the filter bag is conical.
5. A filter as claimed in claim 1 wherein the filter bag is cylindrical.
6. A filter as claimed in claim 1, 2 or 3 wherein the second end of the adaptor has at least one extension configured for retaining the filter to the water storage vessel.
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7. A filter as claimed in claim 6 wherein the extension is a ledge around the periphery of the second end of the adaptor configured for retaining the filter to the inlet of the water storage vessel.
8. A filter as claimed in claim 6 wherein the extension is a flat plate extending on at least one side.
9. A filter as claimed in claim 7 wherein the ledge has a peripheral lip extending downwards.
10. A filter as claimed in claim 1 wherein the open end of the filter bag has a coupler configured for detachably coupling the filter bag to the first end of the adaptor.
11. A filter as claimed in claim 1 wherein the first end has a holder for engaging the filter bag.
12. A filter as claimed in claim 1 wherein the adaptor is made of food grade plastic.
13. A filter as claimed in claim 10 wherein the coupler is made of food grade plastic.
14. A filter as claimed in claim 1 wherein the filter bag is made of fine pore material particularly a non woven sandwiched material.
15. A filter as claimed in claim 1 wherein the filter bag is made of any of cotton cloth, canvas, melt blown polypropylene fabric, melt blown polyester fabric, spun bound
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woven fabric, spun bound non-woven fabric, needle punched polyester fabric, needle punched polypropylene fabric, mix of spun or melt blown fabric and preferably the filter bag is made of non woven needle punched polypropylene fabric.
16. A filter as claimed in claim 1 wherein the filter bag has a pore size in the range of 0.2 to 50 micrometers and preferably the pore size of the filter bag is 5 micrometers.
17. A filter substantially as herein described with reference to and as illustrated by the accompanying drawings.

Dated this 24TH day of July 2008
Essenese Obhan
Of Obhan & Associates
Agents for the Applicant
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