FORM - 2 THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2006
COMPLETE
Specification
(See Section 10 and Rule 13) A HOLLOW CONTAINER
HITECH PLAST LIMITED
an Indian Company,
of C/130, Solaris I, Opp. L&T Gate No. 6, Powai,
Mumbai-400 072, Maharashtra, India.
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

This application is a patent of addition application for Indian Patent Application No. 426/MUM/2007 issued on May 6, 2007, the entire contents of which, is specifically incorporated herein by reference. This application claims priority benefits to the Indian patent application number 426/MUM/2007, filed 6 March, 2007.
FIELD OF INVENTION
The present invention relates to a water purification system and more particularly relates to a portable water filtering and purifying system.
BACKGROUND OF THE INVENTION
One of the oldest methods of holding (storing) water in the outdoors is with the use of bags, one such know bags were used by Aborigines where they carried water in kangaroo skins. In the present day, usually backpackers carry water bag which is specifically used to carry large amount of water, while traveling in groups rather than for personal use only. Another popular method is carrying water in bottles. This is drinking water packed in bottles for individual consumption where drinking water is not readily available or is not clean enough to drink. Currently there exist a number of water bottles which are used to store water, these are expensive and are not environmental friendly. Though the materials used are generally recyclable, many of these bottles, particularly those used in developing countries without recycling infrastructure, are discarded rather than recycled. This has a negative effect on the environment
However, the need is for filtered and purified water which is easily carried in a bottle. Portable techniques for purifying water are used for hiking, camping etc. or

for use in rural areas or emergency situations. Common techniques include boiling, disinfection with tablets, ultra-filtration and the like.
Boiling is not routinely used to purify drinking water except in emergencies. This method works well to make water safe to drink which is contaminated with living organisms. It is recommended that water should be boiled for several minutes in advance of consumption or use, in order to kill as much of the bacteria and viral contamination as possible. The disadvantages of boiling water include that boiling should not be used when toxic metals, chemicals (lead, mercury, asbestos, pesticides, solvents, etc.), or nitrates have contaminated the water. Boiling may concentrate any harmful contaminants that do not vaporize as the relatively pure water vapor boils off!
Other technique available is water purification tablets (comprised primarily of iodine) which may be used to sterilize water and kills most of common pathogens present in natural fresh water sources. Iodine is a lightweight solution for water purification. Kits are available in market that include an iodine pill and a second pill (vitamin C or ascorbic acid) which removes the iodine taste from the water after it has been disinfected. However, a disadvantage associated with the use of water purification tablets is that they leave the water with an unpleasant taste or odor. There are also many polymer and ceramic filters market that incorporates iodine post-treatment in their filter elements to kill viruses. Iodine can also be added to water as a solution, crystal, or in tablets form.
Active carbon filtering system are also used which economically remove wide variety of contaminants like bacteria and protozoa, such as Cryptosporidium and Giardia lamblia, but not viruses which can collect and grow within carbon beds, so

disinfection by chemicals or ultraviolet light is required after filtration. Ultraviolet (UV) light destroys DNA and thereby prevents microbes from reproducing.
Portable water filters have been developed to facilitate a user to obtain clean water wherever user goes, which is readily available and can be reused. It also reduces the probability of contamination of filtered and purified water as it is done inside the water bottle compared to the distilled water which includes many steps prior to drinking. This kind of arrangement helps to cut down the use of distilled water bottle and is user friendly, simple and economical. These kind of water filtration and purifying systems are also know in the art with different filtration technologies to meet some of the problems described above. These filter cartridges particularly include granulated active carbon bed and co-axially aligned resin bed.
Several attempts have been made to manufacture portable water filters.
Accordingly, United State Patent 6569329 discloses a bottle mountable filtration system which includes a plurality of different filter elements or filtering and treatment elements having a common central axis that are mounted to extend into a bottle from a cap with a manual valve. Mounting structures are by screw threads or by an interference fit and connected to the cap. Outer filter treating element comprise a chlorine removal primarily radial flow outer filter, and an inner treatment element comprise medication adding component including a mixing chamber which provides an axial flow chamber radially surrounded by the flavoring.
Again, United State Patent 6004460 discloses a portable bottle having a flexible, hollow body with an opening and a cap for inserting water into an inner

chamber and a control valve for allowing water to be squeezed out of the inner chamber. The bottle comprises a flexible, hollow body having a top and a bottom opening with the inner chamber; a filter assembly permanently secured to an interior surface of the top and extending partway into the inner chamber; the filter assembly includes an elongated cylindrical body having an open central chamber with the open central chamber in fluid communication with the control valve.
These apparatus disclosed hereon above includes a filtering element which is complicated and there by add on to the cost of production. Hence, there was felt a need for a container which can overcome the disadvantages of the prior art.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide a portable filtering bottle assembly.
Another objective is to provide a personal filtering assembly that is easily carried from one place to another.
Still another object of the present invention is to provide a container that can provide the user with filtered water.
Yet another objective of the present invention is to provide a portable filtering bottle that will save a user from buying bottled water.
Yet another objective is to provide a bottle which can be used several times with the available water resource.

Yet another objective is to provide a method of filtering and purifying water with an assembly installed inside a container.
Yet another objective is to provide a purifying assembly which removes microbes like salmonella, pseudomonas and E-coli.
Still another objective is to provide a filtering assembly which filters particulate matter from an impure liquid.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided a hollow container adapted to contain a fluid to be filtered and dispensed, the container comprising:
> an enclosing wall defined by a hollow having a first end and a second end, the fluid is filled in the hollow of the container through said first end, said second end is provided with a filter to purify the fluid adapted to be dispensed from a dispenser;
> a cover fitted to said first end of said hollow, said cover is provided with a recess; and
► a pressure equalizing means fitted to said recess provided on said cover.
Typically, the cover is threadably fitted to the first end of the enclosing wall of the hollow container.
Typically, the pressure equalizing means is a spring loaded valve.

Preferably, the pressure equalizing means is provided with a closure end and an opening end, said closure end is located in the hollow defined by the enclosing wall.
Further, the pressure equalizing means is provided with a washer adapted to cooperate with the closure end of the pressure equalizing means.
Alternatively, the cover can be rotatably displaced to partially open and allow access to the atmospheric pressure to the inside of the hollow container.
Typically, the dispenser is typically a nozzle.
BRIEF DESCRIPTION OF THE FIGURES
Other aspects of the invention will become apparent by consideration of the accompanying drawing and their description stated below, which is merely illustrative of a preferred embodiment of the invention and does not limit in any way the nature and scope of the invention.
Figure 1 illustrates one embodiment of the hollow container in accordance with the present invention; and
Figure 2 schematically illustrates the sectional view of another embodiment of the hollow container in accordance with the present invention.
DETAILED DESCRIPTION
The invention will now be described with reference to the accompanying drawings which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.

Referring to the accompanied drawings, a hollow container, in accordance with this invention is generally indicated by the reference numeral 10 and is particularly shown in figure 1 of the drawing.
The hollow container (10), shown in figure 1, comprises an enclosing wall (11) defining a hollow (12), a cover (20), a filter (14) and a dispenser (16). The hollow container (10) is adapted to hold fluid.
Figure 1 illustrates one embodiment of the hollow container in accordance with the present invention. The enclosing wall (11) is open at both ends so as to define a first end (13) and a second end (15). The fluid is filled inside the hollow container (10) through the first end (13) of the enclosing wall (11). The cover (20) is adapted to be fitted to the first end (13) of the enclosing wall (11) of the hollow container (10). The filter (14) is adapted to be fitted to the second end (15) of the enclosing wall (11). The dispenser (16), typically a nozzle, is fitted to the filter (14). The fluid filled inside the hollow container (10) is allowed to be filtered and dispensed through the dispenser (16).
The cover (20) has a closed end and an open end. The closed end has a first surface (21a) and a second surface (21b). The open end of the cover (20) is adapted to cooperate with the first end (13) of the enclosing wall (11) while the second surface (21b) of the closed ends of the cover (20) is adapted to cooperate with the hollow (12) of the enclosing wall (11).
A pressure equalizing means is provided in order to equalize the pressure inside the hollow container (10) and the pressure outside the hollow container (10). The pressure equalizing means is incorporated by threadably

engaging the cover (20) with the first end (13) of the enclosing wall (11) whereby the loosing of the cover (20) from the first end (13) creates a gap which helps in equalizing the pressure inside the hollow container (10) and the pressure outside the hollow container (10).
Figure 2 schematically illustrates the sectional view of another embodiment of the hollow container wherein the pressure equalizing means is a spring loaded valve (18). The cover (20) at its closed end is provided with a recess (22) in order to accommodate the spring loaded valve (18).
The spring loaded valve (18) comprises a plunger, a spring (25) and a washer (26). The plunger has a recess closure end (24a) and a recess opening end (24b) connected by means of a stub (24c). The spring (25), typically a compression spring is provided between the recess closure end (24a) and the recess opening end (24b) and encloses the stub (24c). The plunger of the spring loaded valve (18) is provided with a half pitch thread lock so that before operating the spring loaded valve (18) as a pressure equalizing means, the plunger with have to be rotated typically for half a rotation to release the plunger for being plunged. After dispensation of the required quantity of water from the hollow container, the plunger is required to be twisted in the reverse direction to prevent unintentional operation of the plunger.
In an inoperative configuration of the spring loaded valve (18), the recess closure end (24a) of the plunger of the spring loaded valve (18) is adapted to abut the second surface (21b) of the closed end of the cover (20) via the washer (26) so as to prevent the outlet of the fluid contained in the hollow

container (10) through the recess (22) of the cover (20). The washer (26) having a hole of a diameter equal to the diameter of the recess (22) of the cover (20) is provided so as to be located between the recess closure end (24a) and second surface (21b) of the closed end of the cover (20). In the inoperative configuration of the pressure equalizing means (18), the spring (25) is in a non-compressed condition.
In the operative configuration of the pressure equalizing means, air from outside the hollow container (10) is allowed to flow inside the hollow (12) of the hollow container (10). In the inoperative configuration of the pressure equalizing means, the fluid inside the hollow (12) of the hollow container (10) is completely cut off from the air outside the hollow container (10).
When the cover (20) of the hollow container (10) is adapted to act as pressure equalizing means, the operative configuration of the pressure equalizing means is achieved by partially opening the threadably fitted cover (20) at the first end (13) of the enclosing wall (11). The inoperative configuration of using the cover (20) as the pressure equalizing means is achieved by tightly closing the threadably fitted cover (20) at the first end (13) of the enclosing wall (11).
In an operative configuration of the spring loaded valve (18), the recess opening end (24a) of the spring loaded valve (18) does not abut the washer and as such air is allowed to enter the hollow (12) of the hollow container (10) through the recess (22) of the cover (20). The operative configuration of the spring loaded valve (18) is obtained by the application of pressure on the recess opening end (24a) of the spring loaded valve (18). In the operative configuration of the spring loaded valve (18), the spring (25) is in

compressed condition so that as soon as the pressure on the recess opening end (24a) of the spring loaded valve (18) is released, the spring (25) rebounds back to its non-compressed state and the spring loaded valve (18) returns back to the inoperative configuration.
In the operative configuration of the pressure equalizing means, the hollow container (10) is in an inverted state such that the nozzle (16) in positioned below the first end (13) of the enclosing wall (11).
When the pressure equalizing means (18) is in the inoperative configuration and the fluid is contained inside the hollow container (10), the pressure inside the hollow container (10) is lower than the pressure outside the hollow container (10). As a result of the difference in the pressure between the inside of the hollow container (10) and the outside air, the fluid from inside the hollow container (10) is not allowed to flow out of the dispenser (16). The fluid is either entirely liquid or partly liquid and partly air.
When the pressure equalizing means (18) is in the operative configuration, the air from outside the hollow container (10) is allowed to flow inside the hollow container (10) through the recess (22) or the gap between the threads of the cover (20) and the first end (13) of the enclosing wall (11). The passage of air from the outside the hollow container (10) to the inside of the hollow container (10) helps in equalizing of the pressure between the outside and the inside of the hollow container (10). The passage of air further increases the weight of the air above the fluid contained in the hollow container (10). As a result of the increase in the weight of the air above the fluid, the fluid by virtue of gravity is allowed to pass through the filter (14)

and flow out through the nozzle (16), thus enabling in dispensing the filtered fluid from inside the hollow container (10),
When the pressure equalizing means moves from the operative configuration to the inoperative configuration, the air outside the hollow container (10) is cut off from the fluid inside the hollow container (10). This result in a pressure difference between the fluid inside the hollow container (10) and the air outside the hollow container (10) which prevents in discontinuing the flow of the fluid contained in the hollow container (10) through the dispenser (16).
TECHNICAL ADVANTAGES
The product as described herein above allows in easy dispensation of the contained fluid. Further, the hollow container of the present invention helps in purifying the fluid contained in the hollow container. Again, the hollow container helps in eliminating the cost involved in purchasing bottled mineral water. Still further, the hollow container is simple in construction and is easy to use. The hollow container of the present invention is long lasting.
The numerical values given of various physical parameters and dimensions are only approximations and it is envisaged that the values higher or lower than the numerical values assigned to the parameters, dimensions and quantities fall within the scope of the invention.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that

many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. These and other changes in the preferred embodiment as well as other embodiments of the invention will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.

We claim:
1. A hollow container adapted to contain a fluid to be filtered and dispensed,
said container comprising:
► an enclosing wall defined by a hollow having a first end and a second end, the fluid is filled in the hollow of the container through said first end, said second end is provided with a filter to purify the fluid adapted to be dispensed from a dispenser;
► a cover fitted to said first end of said hollow, said cover is provided with a recess; and
► a pressure equalizing means fitted to said recess provided on said cover.
2. A hollow container as claimed in claim 1, wherein said cover is threadably
fitted to the first end of the enclosing wall of the hollow container.
3. A hollow container as claimed in claim 1, wherein said pressure equalizing
means is provided with a closure end and an opening end, said closure end is located in the hollow defined by the enclosing wall.
4. A hollow container as claimed in claim 1, wherein said pressure equalizing
means is typically a spring loaded valve, said spring loaded valve comprising a plunger, a spring and a washer.
5. A hollow container as claimed in claim 1, wherein said cover can be
rotatably displaced to partially open and allow access to the atmospheric
pressure to the inside of the hollow container.

6. A hollow container as claimed in claim 1, wherein said dispenser is typically a nozzle.