Title of Invention	AN ION EXCHANGE RESIN CARTRIDGE FOR USE IN WATER FILTERS
Abstract	1. An ion exchange resin cartridge for use in water filters having a water flow shut off mechanism to indicate end of life of the cartridge comprising a resin bed contained between a fixed and a movable perforated support, the said movable support adapted to close the water inlet of the cartridge upon predetermined level of expansion of the resin bed based on effective life of the cartridge

Full Text

FORM -2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE SPECIFICATION (See Section 10) AN 10N EXCHANGE RESIN CARTIDGE FOR USE IN WATER FILTER HINDUSTAN LEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at Hindustan Lever House, 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India GRANTED The following specification particularly describes the nature of the invention and the manner in which it is to be performed. 2-9-2004 Technical field: The present invention relates to a water treatment device and more particularly to a water filter cartridge provided with end-of-life indicator and automatic shutoff mechanism. Background and prior art: Water treatment devices are well known in the art. Such devices are employed directly in a water system, either in-line or at the terminal end, or in self-contained batch systems. An example of an in-line system is an under the counter device which filters water prior to reaching the faucet. Terminal end devices include counter top and faucet mounted filtration. Self-contained batch systems include gravity fed systems or carafe units. Typical water treatment devices employ a mechanical filtration or a chemical element. Mechanical filters treat water by preventing the passage of particulates. As a mechanical filter approaches the end of its useful life, restricted flow due to particulate accumulation provides a ready indication that element replacement is necessary. Chemical treatment (e.g., activated carbon-based and ion-exchange media based) employs processes such as adsorption and ion exchange resin to remove the undesirable contamination. A major drawback associated with chemical treatment is the chemical media eventually becomes inactive, providing no such indication that the useful life of the chemical element has been exceeded. As a result various methods have been employed to indicate end of life to the user. In the method described in US patent no. 4,686,037 the user compares the colour of the pre-filter with a reference strip to determine when the media requires replacement. The problem with this method, however, is that it is inherently subjective and, therefore, subject to error. A more accurate means of indicating end of useful life of conventional treatment units is through devices, which uses a process commonly referred to as "flow totalization". These devices totalize the liquid volume, which is passed through the treatment media. Both electrical and mechanical " flow totalization" devices are known in the prior art. Illustrative are the devices disclosed in US Pat nos. 4,918,426; 5,089,144; 4,681,677. In US Pat. Nos. 4,918,426 and 5,089,144 electrical flow totalization devices are disclosed which employ pressure transducers. These transducers include integrated outputs to calculate total volume. After a predetermined volume is reached, a valve is electrically actuated stop flow. US Pat No. 4,681,677 discloses a mechanical flow totalization device, which employs a table connected with a series of gears. The gears are designed and adapted to mechanically add up the volume of water passed through the device. The gears also operate a valve that is adapted to stop flow after predetermined volume of water has passed through the device. In US Pat No. 5,536,394 a mechanical flow totalization device is disclosed which employs a float mechanism. The float is designed and adapted to rotate a pre¬determined distance upon each cycle of the water treatment unit. Once the float is made a specific number of rotations and has travelled a complete distance across a support rod, the float rests in a position where it is visible through an opening in a housing, indicative of the end of life of the water treatment unit. Although flow totalization devices address the end of life problem(s) there are drawbacks. One major drawback is that the flow totalization devices are often complex and hence expensive. Another important drawback is that such devices will totalize the volume of water flow irrespective of the level of contamination in the water, i.e. they will indicate the end of life even if it means the cartridge has some more useful life left in it. Another drawback is that such devices can, and in many instances will, adversely effect the flow through characteristics of the water treatment device, (i.e. filter cartridge) The present invention relates to end of life indicators for gravity fed water treatment systems which are based on chemical treatment that employ processes such as adsorption and ion exchange resin to remove the undesirable contamination. The invention is based on the increase in volume of the resin that occurs depending on the degree of contamination and solves the problem associated with end of life indicators that are based on flow totalization. It is therefore an object of the present invention to provide for indicating the end of useful life of a water treatment system that is mechanically simple, accurate and reliable. It is a further object of the invention to provide a device for indicating the end of useful life which does not hinder the flow through characteristics of the filter cartridge and which functions based on the remaining useful life of the cartridge and hence will enable the optimum usage of the cartridge. It has now been possible to device a cartridge with end-of-life indicator that functions based on the remaining useful life of the cartridge and hence will enable the optimum usage of the cartridge. Thus, according to the invention there is provided an ion exchange resin cartridge for use in water filters having a water flow shut off mechanism comprising a resin bed contained between a fixed and a movable perforated support, the said movable support is provided with an elastic coupling with a head that being capable of plugging the water inlet of the cartridge upon expansion of the resin bed by 15 to 35% of the original volume. The invention will now be illustrated with reference specific non-limiting embodiments, shown in the accompanying drawings in which Fig. 1 is a design of a multi chambered water filter; Fig. 2 is a plan view of an ion exchange cartridge provided with the end of the life indicator according to the invention ; Fig. 3 is a modular design of the cartridge Fig 1. shows the design of a multi chambered water filter comprising of an upper chamber (C1) which contains the pre-filter (F) to remove the visible sediments by entrapment in the pores and a bottom chamber (C2) to collect the purified water. The upper chamber has also a cartridge (C3) described in Fig 2 and 3, screwed to the adapter (A) that holds the pre-filter (F). The purified water flows out through a tap (T) provided in the bottom chamber. As shown in the plan view in Fig. 2 there is an outer layer of granular activated carbon (AC) contained in the annular portion around the resin cartridge (RC) which is provided with filter pads made up of polymeric fibres (PF) on either ends of the granular activated carbon. (IR) is the central iodinated resin contained in the resin cartridge provided with a fixed perforated support at the lower end (PS 1) and a movable perforated support acting as the indicator disc (PS 2) at the upper end. The indicator disc is attached to a plunger (P) with an elastic coupling (EC) that has a head (AS) capable of plugging the water inlet (O). In the modular design of the cartridge shown in Fig. 3 the activated carbon and the resin chamber have been specially separated. A multi chambered water filter (Fig 1) comprising of an upper chamber which contains the pre filter to remove the visible sediments by entrapment in the pores and a bottom chamber to collect the purified water was tested. The upper chamber has also a cartridge described in Fig 2. Screwed to the adapter that holds the pre-filter. The initial volume of resin in the cartridge was 20 ml and the diameter of the cartridge was 30 mm. Accelerated testing of the filter was carried out to leach the iodine and obtain an increase in volume of the resin. It was possible demonstrate the shut off mechanism when there was an increase in volume (15 - 35%) as mentioned in the invention. As iodine content in the resin is the key to eliminating contaminants in the water the above demonstrates the invention where the iodine is leached out and the shut off mechanism functions. WE CLAIM: 1. An ion exchange resin cartridge for use in water filters having a water flow shut off mechanism to indicate end of life of the cartridge comprising a resin bed contained between a fixed and a movable perforated support, the said movable support adapted to close the water inlet of the cartridge upon predetermined level of expansion of the resin bed based on effective life of the cartridge. 2. An ion exchange resin cartridge as claimed in claim 1 wherein said movable support is adapted to close the water inlet of the cartridge upon expansion of the resin bed by 15 to 30% of original volume. 3. An ion exchange resin cartridge as claimed in claims 1 or 2 wherein said movable support is provided with an elastic coupling with a head portion adapted to close said water inlet of the cartridge. 4. An ion-exchange resin cartridge as claimed in anyone of claims 1 to 3 optionally comprising: an outer layer of granular activated carbon contained in an annular portionaround the resin bed which is provided with filter pads on either ends of the granular activated carbon. 5. An ion-exchange resin cartridge as claimed in anyone of claims 1 to 4 wherein the resin is an iodinated resin and the cartridge is provided with a fixed perforated support at the lower end and a movable perforated support acting as the indicator means at the upper end. 6. An ion-exchange resin cartridge as claimed in anyone of claims 1 to 5 wherein said indicator means is attached to a plunger with an elastic coupling having a head adapted to close said water inlet upon expansion of resin bed by 15-35% of the original volume. 7. An ion exchange resin cartridge as claimed in anyone of claims 1 to 6 wherein said filter pads are obtained of polymeric fibres. 8. An ion exchange resin cartridge as claimed in anyone of claims 4 to 7 wherein said activated carbon and the resin chamber are separated. 9. An ion exchange resin cartridge adapted to be fitted with water filter as claimed in anyone of claims 1 to 8, said water filter comprising - multi chambered filter having an upper chamber containing a pre-filter adapted to remove visible sediments by entrapment in the pores and a bottom chamber to collect the purified water; said bottom chamber having said ion exchange resin cartridge with said means for indicating the end of life. 10. An ion exchange resin cartridge for use in a water filter substantially as herein described and illustrated with reference to the accompanying figures. Dated this 13th day of November 2000 Dr.Sanchita Ganguli Of S.MAJUMDAR & CO. Applicant's Agent

Documents:

1011-mum-2000-cancelled pages(2-9-2004).pdf

1011-mum-2000-claims(granted)-(2-9-2004).doc

1011-mum-2000-claims(granted)-(2-9-2004).pdf

1011-mum-2000-correspondence(ipo)-(12-12-2005).pdf

1011-mum-2000-correspondence1(8-11-2001).pdf

1011-mum-2000-correspondence2(15-4-2005).pdf

1011-mum-2000-drawing(2-9-2004).pdf

1011-mum-2000-form 1(13-11-2000).pdf

1011-mum-2000-form 19(23-6-2003).pdf

1011-mum-2000-form 2(granted)-(2-9-2004).doc

1011-mum-2000-form 2(granted)-(2-9-2004).pdf

1011-mum-2000-form 3(8-11-2001).pdf

1011-mum-2000-form 5(8-11-2001).pdf

1011-mum-2000-power of attorney(10-11-2003).pdf

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