FIELD OF INVENTION:
This invention relates to an improved gravity flow UV radiation based storage water purifier ensuring better purification and decontamination of water. This purifier also provides palatable drinking water minimizing after taste of chemical purifiers.
BACKGROUND ART:
Gravity flow water purifiers cum filter presently available in market are housed with top and bottom container. Raw input water is poured at the top chamber and purified and filtered water is collected at and stored in the bottom chamber, which is then drawn by the consumer. The purification is based on chemical disinfection.
This type of water purifiers have inherent problems of air block, over flowing of water, water leakage.
Also the current purifiers depend on chemical based purification for removal of micro-organism, which have inherent problems like exhaustion of chemicals, which is difficult to recognize and stop usage thereby not ensuring safe drinking water to
user.
Chemical based purification leaves an after-taste in the drinking water, which is not appreciated by the consumer.
Most of the current UV based water purifiers available in the market are on¬line systems and are dependent on electricity and running water for operation. It would not be possible to draw safe drinkine water in the absence of anv of these basic requirements.

The main objects of this invention is to develop gravity flow water purifier cum filter which avoids the above mentioned drawbacks and to provide safe drinking water system to customer, a UV lamp which produces UV radiation of 253.7 nm is incorporated for disinfection of water. A micro switch to prevent the overflow of water, water leakage sensor. Pre-programmed Electronic UV lamp and SMPS power supply are also provided.
DETAILS OF INVENTION:
The gravity flow storage water purifier according to this invention comprises top, middle and bottom chambers, said top chamber being provided with a water inlet, particulate filter means, sediment filter means and activated carbon block in the flow path of incoming water, said top chamber in fluid communication with said bottom chamber which is provided with an outlet means and a float valve, water from said top chamber flowing into said bottom chamber through conduits, passing through said middle chamber which houses a UV radiation lamp, in the flow path of water, a PCB, power supply means and a solenoid valve.
Different stages involved in water purification detailed herein below:
Non Woven PP cloth particulate filter bag of predefined micron rating is provided for removal and reduction of physical impurities.
A Non Woven PP cloth sediment filter layer of predetermined micron rating is provided for removal and reduction of physical impurities of finer size.
Packed Activated Carbon Block of predefined shape, size and micron rating is provided for removal and reduction of hazardous organics, chlorine, and chlorine

byproducts, pesticides, foul odor, colour and very fine suspended particles. These are housed in the top chamber.
Germicidal UV radiation of predefined dosage for disinfection of water by inactivation and elimination of water bom disease causing bacteria, viruses and protozoan is provided in the middle chamber.
The present invention works in universal voltage range from 50-270 V, it is provided with "Pre-Programmed Electronic UV Lamp electronic Ballast, SMPS power supply, a solenoid valve, micro float power supply switch, water availability sensor, and a leak detector in the mid part. This circuit is suitable for UV lamps ranging from 4W to 15W.
All electronic and electrical parts are concealed in the middle part of the unit. The invention consists of LED, which indicates in the front of the unit, communicating the process and service functions of the unit.
Overflow protection - is provided to avoid overflow when the bottom tank gets full and the user fills the top tank with out emptying the bottom tank. A float with a micro flow switch achieves this function.
Dry Protection - means provided does not work and goes into "sleep" mode, in case the top tank is empty and space is available for water in bottom tank. This is achieved by a water level sensor fitted in the water route inside the mid part or top tank. The unit automatically resumes normal functioning when the water is filled in the top tank.

Water leakage protection - is provided to detect leakage or seepage of water into mid part. This unit does not work and goes into "stand -by" mode. The unit would resume its normal activity only after the water is removed from the mid part.
Fail safe - the water stops flowing into bottom tank and unit goes into stand by mode in case the UV Lamp fails to glow due to any reason.
Water flows into the bottom tank only when all the following conditions are met
a. UV lamp is ON
b. Water is available in the top tank
c. Space for water is available in bottom tank
d. Water has not seeped/ percolated into the mid part
Water stops flowing into the bottom tank when any of the following conditions has occurred.
a. UV lamp does not glow or is in fiised state
b. Bottom tank is fiill with water up to defined capacity level
Lamp will shut off
a. If bottom tank is full with water up to defined capacity level
b. No water is available in top tank
c. Water leaks into the mid part.
Advantages of this unit are that minimum human intervention is required and is integrated and compact.

This invention will now be described with reference to the single figure in the accompanying drawings which is a sectional view of this water purifier.
Details of parts indicated by corresponding reference numerals are given below.
Reference numerals 1 to 23 indicate the following:

Obvious modifications and alterations known to persons skilled in the art are within the scope and ambit of the appended claims.

WE CLAIM:
1. A gravity flow storage water purifier comprising top, middle and bottom chambers, said top chamber being provided with a water inlet, particulate filter means, sediment filter means and activated carbon block in the flow path of incoming water, said top chamber in fluid communication with said bottom chamber which is provided with an outlet means and a float valve, water from said top chamber flowing into said bottom chamber through conduits, passing through said middle chamber which houses a UV radiation lamp, in the flow path of water, a PCB, power supply means and a solenoid valve.
2. The water purifier as claimed in claim 1, wherein said UV lamp emits radiation of 253.7nm power by lamp of 4W to 15W and the particulate and sediment filters are of woven polypropylene.
3. The water purifier as claimed in claims 1 and 2, wherein LEDs are provided in the middle chamber to indicate the process stages of said purifier.
4. The water purifier as claimed in claims 1 to 3, wherein means to protect
overflow of water, water leakage protection means and means to stop water
flow through the middle chamber during UV lamp failure are provided in the
middle chamber.

5. A gravity flow storage water filter substantially as herein described with
particular reference to the single figure in the accompanying drawings.