There is a significant demand for filtered drinking water, and while this is oftentimes fulfilled with home tap water filters, or by the purchase or use of bottled water, neither are susceptible to ready portability. It is desirable to be able to have filtered drinking water even during travel situations, whether by car, public transportation, or bicycle, and it would be especially desirable to provide a filtering assembly for use with standard plastic water bottles, which filter assembly has optimum portability, for example being capable of being carried in a pocket, purse, fanny pack, or the like. It is especially desirable to be able to have such portability while at the same time being able to filter chlorine out of drinking water. Chlorine has been linked to both arterial disease and types of cancer, and chlorinated water oftentimes has an undesirable taste, as can organic contaminants in the water.
According to the present invention a filter assembly, and a container for dispensing filtered water, are provided which address the needs discussed above. According to the present invention a filter assembly is provided which has almost optimum portability, yet is capable of effectively treating drinking water to remove chlorine and organic taste contaminants therefrom and reduces a variety of chemical contaminants. The filter assembly according to the present invention, for example, is capable of providing at least a 50% reduction in chlorine at a 5 ml/second flow rate of water therethrough, small enough not only to be portable but to be readily mounted in the next or open end of a conventional plastic bottle, such as conventional plastic water bottles, including conventional plastic water bottles having necks with an internal diameter of about 25-50 mm. There is a great deal of versatility associated with the filter assemblies and containers according to the present invention, the actual filter element being connected to the other components either adhesively, mechanically, or by welding (e.g. sonic welding), a cap with which the filter is associated being adaptable to fit any type of closure mechanism on a conventional plastic bottle or the like, and the assembly also including a valve through which the water may be dispensed
According to one aspect of the present invention a filter assembly for use with a bottle having a circular cross-section neck or open end to simultaneously cap the neck or open end and filter liquid (typically drinking water) poured out of the bottle through the neck or open end, is provided. The assembly comprises the following components: A tube of filtering material, having a substantially continuous liquid-porous side wall, a hollow interior, a first closed end, and a second open end. A cap for the bottle neck or end, having a fitting portion thereof for cooperating with the bottle neck or end and closing the neck or end, the cap having first and second substantially opposite surfaces. A valve operatively associated with the cap. And, the tube operatively connected to the cap second surface at the tube second open end.
The tube may be adhesively connected to the cap second surface, but preferably is welded (e.g. sonically welded) to it, or is mechanically connected to it. For example a mechanical connection may comprise an O-ring received by cooperating grooves formed in the tube and the cap second surface, or the tube may include a flange extending substantially perpendicularly to the hollow interior, the cap comprising one or more projections for engaging the flange, and the flange and one or more projections providing the mechanical connection, or a locking taper slip fit between the cap closure and filter assembly.
The valve may comprise a baby bottle nipple, a spray valve, or a reciprocating valve of the type conventionally used with plastic water bottles for bicyclists. Such a reciprocating valve has an open first position in which an end portion thereof is most removed from the cap and a closed second position in which the end portion is closest to the cap.
The tube typically has an outside diameter of about 50 mm or less, and is smaller than the bottle neck with which it is to be used, e.g. an outside diameter of less than 25 mm (e.g. about 22 mm) for a conventional plastic water bottle having a 25 mm neck opening.
The cap fitting portion may comprise an internally screw threaded portion or a snap portion. Other types of connections may also be provided, such as bayonet type connections, accessory holding members, or the like.
One preferred composition of filtering material is activated carbon, typically with a binder. For example the filtering material may comprise about 95-30%, about 80-325 mesh, activated carbon powder or granules. The binder may comprise 5-60%, about 75-135 mesh, plastic resin granules. Inert and other types of materials, such as zeolytes, may also be included in the filtering material with which the binder comprises an integral tube. The filter typically has a porosity of about 10-120 microns. To ensure removal of cysts, or other fine particulates, a wrap of filter material having a pore size of about 1-4 microns (e.g. about 1-2 microns) may be disposed exteriorly around the filtering material tube side wall and first closed end. Also other types of water treatment materials may also be utilized, such as a biocidal media disposed within the hollow interior of the filter tube.
According to another aspect of the present invention a container for dispensing filtered water is provided. The container comprises the following components: A plastic bottle having an open neck with an inside diameter of about 50 mm or less, and with a cap engaging portion. A plastic cap having a bottle neck engaging portion, the cap and neck engaging portions cooperating to releasably hold the cap on the neck, the cap having first and second substantially opposite surfaces. A tube of or containing filtering material capable of reducing the level of chlorine in water passing therethrough by at least 50% at a flow rate of 5 ml/second, the tube having a substantially continuous side wall, a hollow interior, a first closed end, and a second open end. A valve operatively associated with the cap. And, the tube operatively connected to the cap second surface, and the tube having an outside diameter less than the inside diameter of the neck.
The tube may comprise activated carbon and binder, the side wall and closed end being liquid porous, or may be of solid plastic with openings or porous plastic and contain filtering media. The bottle neck inside diameter may be about 25 mm, the tube outer diameter about 22 mm, with the tube having a length of about 55-75 mm. The bottle is inverted during use, and valving action may be provided by an air vent formed in the closed end of the tube, e.g. a hole small enough so that liquid may not pass through it but so that air may (e.g. a circular hole having a diameter of about 0.02 mm).
It is the primary object of the present invention to provide a simple yet effective portable filter assembly and container for dispensing filtered water utilizing such a filter assembly. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.