U.S. patent application number 10/001833 was filed with the patent office on 2002-03-28 for universal filter for soda pop and bottled water bottles.
Invention is credited to Bryan, Raymond G., Hughes, Douglass E..
Application Number | 20020036176 10/001833 |
Document ID | / |
Family ID | 27414906 |
Filed Date | 2002-03-28 |
United States Patent
Application |
20020036176 |
Kind Code |
A1 |
Hughes, Douglass E. ; et
al. |
March 28, 2002 |
Universal filter for soda pop and bottled water bottles
Abstract
Embodiments of a portable water filter are described and shown,
each embodiment being adapted to fit and seal into a bottle neck
without modification of, or attachment to, the bottle or its cap or
other closure. The filter has a flange system that rests on the lip
of the bottle neck and that has slanted or curved surfaces to seal
with the neck and the bottle cap when the cap is screwed onto the
bottle. The filter further includes a connector for attachment to a
straw for an alternative use of the filter in a cup or mug. The
filter water inlets are preferably in the lower region of the
filter housing, to facilitate suctioning of the liquid from the
bottom of the cup or mug even when the liquid level is low.
Additional liquid inlet(s) may be added to the upper region of the
filter housing, preferably sized and located to drain the last,
small amount of liquid in the neck of a bottle when the bottle is
inverted, without sucking in enough air in the mug-use application
to interfere with adequate draining of the mug or cup.
Inventors: |
Hughes, Douglass E.;
(Boulder, CO) ; Bryan, Raymond G.; (Reno,
NV) |
Correspondence
Address: |
Steven C. Petersen
Hogan & Hartson, LLP
Suite 1500
1200 17th Street
Denver
CO
80202
US
|
Family ID: |
27414906 |
Appl. No.: |
10/001833 |
Filed: |
November 16, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10001833 |
Nov 16, 2001 |
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09525106 |
Mar 14, 2000 |
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09525106 |
Mar 14, 2000 |
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08988864 |
Dec 11, 1997 |
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08988864 |
Dec 11, 1997 |
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08685334 |
Jul 23, 1996 |
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5840185 |
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Current U.S.
Class: |
210/767 ;
210/282; 210/464; 210/473 |
Current CPC
Class: |
C02F 1/003 20130101;
B01D 35/02 20130101; C02F 2307/02 20130101; C02F 1/002 20130101;
C02F 2201/006 20130101; B01D 35/04 20130101 |
Class at
Publication: |
210/767 ;
210/282; 210/464; 210/473 |
International
Class: |
B01D 037/00 |
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A filter assembly comprising: a radial flow filter element
comprising a cylindrical body of filtering material having a first
end through which filtered water flows, and a second end opposite
said first end; a cylindrical housing having a housing top and a
housing body having a top end and a bottom end for receiving said
filter media, said housing bottom end having a smaller diameter
than said housing top end so that there is a space between said
filter element and said housing, wherein said housing top secures
said housing body around said filter element; and a drinking straw,
wherein said filter media is operatively connected to said
straw.
2. The filter assembly of claim 1, further comprising a stem
extending from the top end of said housing top and in fluid
communication with the filter element, said stem adapted for
attachment to said straw to suction liquid from a liquid
container.
3. The filter assembly of claim 1, further comprising fluid inlets
in the bottom 1/4 to 1/3 of said housing body.
4. The filter assembly of claim 1, wherein said filter media is a
carbon block.
5. The filter assembly of claim 1, further comprising an umbrella
valve positioned in the bottom of said housing body.
6. A filter assembly in combination with a container having an open
end opposite a bottom, said filter assembly comprising: a radial
flow filter element comprising a cylindrical body of filtering
material having a first end through which filtered water flows, and
a second end opposite said first end; a cylindrical housing having
a housing top and a housing body having a top end and a bottom end
for receiving said filter media, said housing bottom end having a
smaller diameter than said housing top end so that that is a space
between said filter element and said housing, wherein said housing
top secures said housing body around said filter element, said
filter media first end operatively connected to a drinking straw,
wherein said straw extends through the open end of said
container.
7. The filter assembly of claim 6, further comprising fluid inlets
in the bottom 1/4 to 1/3 of said housing body.
8. The filter assembly of claim 6, wherein said filter media is a
carbon block.
9. The filter assembly of claim 6, further comprising an umbrella
valve positioned in the bottom of said housing body.
10. A method of filtering a liquid contained in a bottle having an
open end, comprising: providing a filter comprising a filter media
and a housing having a top end and a bottom end for receiving said
filter media, said housing further comprising a flange having a
generally horizontal portion and a generally vertical portion;
inserting said filter into said bottle neck; and securing said
filter in said bottle neck by attaching a bottle tip closure having
a lower surface to said open end of said bottle, wherein the
horizontal portion of said flange extends between and forms a seal
with the open end of said bottle and said bottle closure.
11. The method of claim 10, wherein said flange further comprises a
generally vertical portion having an inner surface and an outer
surface, wherein said outer surface has an area slanted outward
from vertical to said horizontal portion for sealing with the open
end of said bottle, wherein said inner surface of the flange has a
radiused area for sealing with a lower surface of said bottle
closure between the horizontal portion and the vertical
portion.
12. The method of claim 11, wherein said inner surface radiused
area has a radius of about 0.125 inches.
13. The method of claim 11, wherein said inner surface further has
a slanted area at about 45 degrees from horizontal for sealing with
the closure sealing ring.
14. The method of claim 11, wherein said area slanted outward from
vertical is slanted outward at about 15 degrees from vertical for
sealing with the bottle neck.
15. The method of claim 10, wherein the filter media is a carbon
block.
16. The method of claim 10, wherein the container substantially
surrounds the filter media.
17. The method of claim 10, further comprising a stem extending
from said top end of said container in fluid communication with the
filter media for connection to a straw.
18. The method of claim 10, wherein said horizontal portion extends
out past the outer diameter of said bottle neck.
19. The method of claim 10, wherein the filter has one or more
fluid inlets in the bottom 1/4-1/3 of the container.
20. The method of claim 19, further comprising at least one fluid
inlet near the top end of the container.
21. The method of claim 10, wherein said container further
comprises an umbrella valve positioned in the bottom of said
container.
22. A method of filtering a fluid in a non-bottle shaped container,
comprising: providing a filter having bottom end and comprising (a)
a filter media, (b) a housing having a top end and a bottom end for
receiving said filter media, said housing further comprising a stem
extending from the top end of said housing in fluid communication
with said filter media, and (c) a straw connected to said stem; and
inserting said bottom end of said filter into said non-bottle
shaped container.
23. The method of claim 22, wherein said straw is inserted into
said stem.
24. The method of claim 22, wherein said stem is inserted into one
end of said straw.
25. The method of claim 22, wherein the filter has one or more
fluid inlets in the bottom 1/4-1/3 of said housing.
26. The method of claim 22, further comprising an umbrella valve
positioned in the bottom of said housing.
27. A filter assembly connected to a straw drinking tube for use
with a container full of a liquid comprising a filter casing and
filter element that are both tube shaped, and in which there is a
small pre-filtration chamber created by leaving a small void or gap
of from about 0.05 to 0.10 inches between the outer diameter of
said filter element and the inner diameter of said filter casing,
wherein the filter assembly has a top end and a bottom end is
entirely closed except for at least on vent positioned at said
bottom end of the filter assembly, such that when there is a
pressure differential or vacuum caused by a sucking action on the
straw drinking tube, the liquid inside the container is drawn
upwardly into said pre-filtration chamber through said at least one
vent so as to first flood the entirety of the pre-filtration
chamber, thereby establishing a liquid flow pattern in which siad
liquid to be filtered flows evenly around the entire length of the
outside diameter of said filter element regardless of the height of
the level of the water inside of the container.
Description
CROSS-REFERENCE TO OTHER PATENT APPLICATIONS
[0001] This application is a continuation of a prior U.S. Patent
Application, entitled "Universal Filter for Soda Pop and Bottled
Water Bottles," filed Mar. 14, 2000, Ser. No. 09/525,106 which is a
continuation-in-part of a prior, U.S. Patent application, entitled
"Universal Filter for Soda Pop and Bottled Water Bottles," filed
Dec. 11, 1997, Ser. No. 08/988,864, now abandoned, which in turn is
a continuation-in-part of U.S. Patent application, entitled "Sports
Bottle Filter Cartridge," filed Jul. 23, 1996, Ser. No. 08/685,334,
now U.S. Pat. No. 5,840,185, all of which are herein incorporated
by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to portable water filters
for removing chlorine and other components that contribute to poor
taste and odor. More specifically, this invention relates to a
water filter that (i) may be either inserted into the neck of many
current commercial plastic soda pop and mineral water bottles to
make desirable the re-use of these bottles for drinking filtered
tap water or (ii) attached to a straw and used in an open container
such as a mug.
[0004] 2. Description of the State of the Art
[0005] Today there is a growing awareness of problems with our tap
water. Many people are mainly concerned with the taste of tap
water, and secondarily concerned for health-related problems due to
contaminants in water. Because of this, there have been increased
sales of bottled water and of home water filters over the past ten
years. Since it is often difficult to find clean, chlorine-free
drinking water away from home, bottled water has become the
accepted method of finding potable drinking water while away from
home. Bottled water has also become the preferred water for
home-use where the user has no need for a water filter to remove
the chlorine, lead, Cryptosporidium, etc., from the tap water. Most
home filtration devices are relatively expensive, which discourages
families and small businesses from purchasing these filtration
systems. In addition, there is the convenience factor of purchasing
one or two bottles of drinking water at the supermarket. Therefore,
when the consumer purchases bottled water, he or she is not just
buying the water, but the convenience of having it in a half- or
one-quart container.
[0006] In the typical home or business, there are many empty
mineral water or pop bottles, that are destined for garbage.
Because of their great numbers, it would be very convenient to
reuse these soda pop or mineral water bottles for drinking water.
However, as discussed above, it is usually inconvenient to produce
filtered water to pour into these bottles, and, even if the
consumer does so, he or she quickly consumes the bottle-full of
filtered water away from home and is back to having to refill the
bottle with tap water at a business, a friend's home or a public
place.
[0007] There is still a need, therefore, for an economical and
easy-to-use portable water filter for use with mineral water and/or
pop bottles. There is still a need for such a filter that fits
universally into a large number of the otherwise-discarded plastic
bottles in our homes and businesses, without necessarily requiring
modification of the bottles or their caps or in the alternative a
filter that may be used.
SUMMARY OF THE INVENTION
[0008] Accordingly, it is a general object of this invention to
provide a liquid filter system that removes chlorine, heavy metals,
taste, color, odor and microorganisms from water while at the same
time is simple and sanitary to use.
[0009] Another object of the invention is to provide a filter in
that is so versatile that it can fit into a variety of neck
bottles, including existing 28 mm system neck bottles which account
for nearly all of the soda pop and mineral water bottles made and
distributed throughout North America.
[0010] A further object of the invention is to provide a liquid
filter system that can also be used in combination with a straw
within an open container such as a mug.
[0011] Additional objects, advantages and novel features of this
invention shall be set forth in part in the description that
follows, and in part will become apparent to those skilled in the
art upon examination of the following specification or may be
learned by the practice of the invention. The objects and
advantages of the invention may be realized and attained by means
of the instrumentalities, combinations, compositions, and methods
particularly pointed out in the appended claims.
[0012] To achieve the foregoing and other objects and in accordance
with the purposes of the present invention, as embodied and broadly
described therein, the apparatus of this invention may comprise a
filter media held by a container that may be inserted into a bottle
neck, and a flange system connected to the container that rests on
and forms a seal between the bottle neck and the bottle closure. In
addition, the present invention preferably is adapted to be used
with a straw, so that the straw-plus-filter unit may be used in the
bottom of a mug or cup.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings, which are incorporated in and
form a part of the specification, illustrate the preferred
embodiments of the present invention, and together with the
description serve to explain the principles of the invention.
[0014] In the Drawings:
[0015] FIG. 1 shows a perspective, expanded side view of one
embodiment of the invented filter system, with the filter
positioned for installation in the neck of a plastic bottle.
[0016] FIG. 2 shows a perspective, expanded side view of the
embodiment of FIG. 1, with the filter positioned in the bottle
neck.
[0017] FIG. 3 shows a perspective, expanded side view of the
embodiment of FIG. 1, with the filter positioned in the bottle neck
and the top closure installed to seal the filter in the bottle.
[0018] FIG. 4 shows a cross-sectional, side view of the filter of
FIG. 1, installed in an alternative embodiment of a plastic
bottle.
[0019] FIG. 5A is an enlarged, detailed view of the preferred
sealing flange system of the invented filter of FIG. 1 indicated by
dashed lines in FIG. 4.
[0020] FIG. 5B is an enlarged, detailed view of the sealing flange
system of the present invention similar to the view shown in FIG.
5A but illustrating an alternative connection between the sealing
flange system of the present invention and the bottle closure prior
to tightening the bottle closure on the bottle neck.
[0021] FIG. 5C is an enlarged, detailed view of the sealing flange
system of FIG. 5B illustrating the alternative location of contact
between the sealing flange system of the present invention and the
bottle closure top after tightening to obtain a water tight
seal.
[0022] FIG. 6 is a perspective, expanded side view of the filter
embodiment of FIG. 1.
[0023] FIG. 7 is a cross-sectional, expanded side view of the
filter embodiment of FIG. 1.
[0024] FIG. 8 is a side, cross-sectional view of the filter of FIG.
1, installed with an alternative top closure (38'), with arrows
showing water flow from the squeezed bottle through the filter and
through the top closure.
[0025] FIG. 9 is a side, cross-sectional view of the filter of FIG.
8, with arrows showing air flow through the top closure, past the
umbrella valve, and into the bottle.
[0026] FIG. 10 is a perspective view of another embodiment of the
filter, including a slit for draining the last liquid from an
inverted bottle.
[0027] FIG. 11 is a perspective view of the filter of FIG. 1
attached to a straw for use in a mug.
[0028] FIG. 12 is a perspective view of the filter of FIG. 1
attached to a straw for use in a cup.
[0029] FIG. 13 is a side, cross-sectional view of the filter flange
system of FIG. 6, having a gasket installed on the flange's lower
surface.
[0030] FIG. 14 is a side, cross-sectional view of the filter flange
system of FIG. 6, having a gasket installed on the flange's lower
and upper surfaces.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] The filter of the present invention cooperates with the
necks of a variety of bottles to create an effective seal to
prevent leaks and to effectively filter the bottle's contents,
without the filter being connected or attached to either the bottle
or to its closure, and without requiring modification of either the
bottle or the closure. This is accomplished by making the filter
unit just slightly smaller in diameter than the average bottle
interior neck size, except for the special flange system near the
top of the filter that extends radially outward over the top of the
neck and that has a lower portion with a tapered/slanted outer
surface that interferes slightly with the bottle neck inner surface
when the filter is dropped into the neck (as shown in FIG. 5B). As
the top closure is pressed down on the flange system, the flange
will expand slightly to make a water tight seal with the bottle
neck. This flange is preferably adapted to cooperate with a sealing
member on the closure, such a generally cylindrical,
downwardly-protruding, flexible ring, herein also called a "knife
edge." This ring is common to many pop-top closures sold with water
and pop bottles, as it is effective in sealing even a pressurized,
carbonated liquid in the bottle. In some embodiments of the present
invention, adaptation of the flange, to seal with the
downwardly-protruding ring and to flex and seal with the bottle,
may be similar to the invented sealing system of the
herein-incorporated disclosure of U.S. patent application Ser. No.
5,840,185, by Douglass Hughes, et al.
[0032] After the invented filter is inserted into the neck of a
plastic bottle and a top closure is screwed down, water from the
bottle passes through the filter and up through the closure to the
user's mouth, as the user squeezes the sides of the plastic bottle.
A top closure is necessary in this bottle-neck application to allow
the filter system to function as intended. A top closure may be
supplied as an accessory with the filter at the point of sale, in
case a suitable closure is not available with the bottle.
Alternatively, the filter has a port which may be attached to a
straw and thus the filter may be used in a mug or cup.
[0033] Referring to the Figures, there are shown several, but not
the only, embodiments of the invented portable water filter. The
preferred filter 10 is dual-use, in that it may be either installed
in a bottle neck 12, or attached to a straw 14 for use in a mug 16
or cup 18. FIGS. 1-5A, 8, and 9 illustrate the filter 10 sealed in
the neck 12 of a "standard" bottle 13, which may be selected from
the many bottles on the market that have an approximately 28 mm
outside thread diameter neck. FIGS. 11 and 12 illustrate the filter
10 in use with a straw, at or near the bottom of a container. In
either use, the filter 10 does not need to be attached to the
bottle or container or any closure member, and the bottle,
container, and closure member need not be modified from their
standard shape and configuration for use with the invented filter
10.
[0034] The filter 10 comprises a housing 19, which comprises a
housing body 20 and a housing top 22. The elongated body 20 is a
generally cylindrical casing, preferably constructed from a
polypropylene or an ABS material, which houses or ABS, casing which
houses a liquid filter 24. Filter 24 is typically a tube shaped
filter which is open at both ends with an outside diameter and an
inside diameter and a center core 34, made either of a solid but
liquid porous carbon block 24 or of a sintered polymer and powdered
activated carbon such that the filter is liquid porous. The housing
top 22 is attached to the top of the body 20 to enclose the filter
tube 24 and secure the filter tube 24 inside the housing 19. The
housing 19 has an aperture 30 through the center of the bottom wall
of the body 20 and an aperture 32 through the center of the housing
top 22. The filter 24 has a tube-like construction with a center
core 34. These housing and filter tube apertures and core result in
a bore or central passage 36 extending straight though the middle
of the filter 10 at the longitudinal central axis of the filter.
This passage 36 is used to conduct water that has flowed radially
from the outside diameter of the filter tube 24 into the core 34,
and up and out the top of the filter 10 (FIG. 8). The same passage
36 is also used to conduct air returning into the bottle 13 (FIG.
9).
[0035] The housing 19 is preferably specially adapted to cooperate
with the bottle neck 12 to create a seal between the filter housing
and the bottle and between the filter housing and the top closure
38. The outer surface 40 of the body 20 is tapered to allow easy
insertion of the filter 10 into the neck 12. The housing top 22 has
a flange system, herein called the flange 50, which rests on the
lip of the bottle neck 12 and seals with the inner surface of
bottle neck 12. The flange 50 has a generally vertical lower
portion 42 and a generally horizontal portion 44 (when in the
orientation shown in FIGS. 1-4). The outer surface 46 of the lower
portion 42 has a tapered area 48 that tapers upwardly and outwardly
at about 15 degrees to vertical (preferably in the range of 10-20
degrees). This tapered area 48 around the housing top 22 seals with
the top inner surface 52 of the bottle neck 12, especially when the
flange 50 flexes slightly outward in response to the closure 38
being screwed down on top of the flange 50.
[0036] In general, the invented filter may be said to insert itself
between the bottle neck and the top closure without disrupting the
original sealing mechanisms. The filter flange surfaces replicate
original sealing surfaces to an extent that allows the top closure
and bottle to seal to the filter instead of to each other.
[0037] In use in the bottle neck, the top closure 38, 38', screws
down onto the neck 12, with the horizontal portion 44 of the flange
50 between the top surface of the neck and a portion of the bottom
surface of the closure 38, 38'. Typically, the portion of the
closure bottom surface that contacts the flange 50 comprises a
cylindrical shoulder 54 that protrudes downward from the closure.
This shoulder in many, if not all, embodiments of so-called 28 mm
style closures available on the market today is expected to contact
the upper surface horizontal portion 44 (as shown in FIGS. 5B and
5C) sufficiently to create a seal between the closure 38, 38' and
the horizontal portion 44. In addition, the shoulder 54 preferably
places enough pressure on the flange 50 to slightly flex it outward
to seal against the neck inner surface, as discussed above.
[0038] In the preferred embodiment of the top closure 38 and
sealing system shown in FIG. 5A, the shoulder 54 includes a thin,
flexible, generally downwardly-protruding "knife edge" ring or
annular valve seal 56 that acts as the contacting member for
abutting against, and sealing with, the flange 50. The preferred
flange 50, therefore, has a slanted and/or radiused corner that
forms the transition between the upper surface of the horizontal
portion 44 and the inner surface of the lower portion 42. This
slanted and/or radiused corner provides a surface for the annular
valve seal 56 to contact and seal against, as the ring tends to
flex inward as it is forced down against the flange. Thus, the
annular valve seal 56 takes the general shape shown in FIG. 5A,
sealing effectively against the flange and applying pressure to
slightly flex the flange outward.
[0039] The most preferred embodiment of the corner of the flange
50, shown in FIG. 5A, includes a slanted area 60 (at about 45
degrees from horizontal) that joins to a radiused area 62 (at about
R 0.125 inches). This preferred slant and radius combination
provides an effective sealing surface, but other slants and
curvatures may also be operable, for example slants in the range of
30-60 degrees or other ranges. In general, the corner may be
described as more effective if it is "rounded off" or radiused.
Whereas the preferred slanting of the corner as disclosed in the
herein-incorporated U.S. Pat. No. 5,840,185 (10-20 degrees from
vertical), is most effective for a typical sports bottle
downwardly-protruding annular valve seal, the most effective corner
shape for use with the thin, flexible annular valve seal 56 of this
closure and bottle design has been found to be a radiused corner
with a 45-degree slant near the top of the corner.
[0040] In an alternate embodiment, as briefly described above and
illustrated in FIGS. 5B and 5C, effective sealing surfaces are
obtained between the neck 12, the flange 50, and the top closure
38, 38' when the thin, flexible annular valve seal 56 contacts the
flat, upper surface of the horizontal portion 44 of the flange 50,
rather than mating with slanted area 60 of the flange 50 as in FIG.
5A. The present invention provides effective sealing because as the
top closure 38, 38' is screwed down onto the neck 12 the flexible
annular valve seal 56 compresses as it is pressed against the
horizontal portion 44 to provide a circular sealing surface between
the top closure 38, 38' and the flange 50. Additionally, as
discussed above, shoulder 54 of the top closure 38, 38' applies
sufficient pressure on the flange 50 to slightly flex it outward
against the neck 12 inner surface to obtain a tight seal between
the flange 50 and the neck 12. More particularly, FIG. 5B
illustrates initial assembly with flange 50 inserted into neck 12
having a slightly smaller inner diameter than the outer diameter of
the flange 50 and with annular valve seal 56 of top closure 38, 38'
about to make contact with horizontal portion 44 of flange 50. The
tapered area 48 of the lower portion 42 of the flange 50 abuttingly
contacts the neck 12 but a gap is formed between the horizontal
portion 44 of the flange 50 and the neck 12, because as discussed
above the radius of tapered area 48 is greater than the inner
radius of bottle neck 12. Hence, tapered area 48 extends radially
outward over the top of the neck 12 and thus rests on the bottle
neck 12 when filter 10 is initially inserted into the bottle neck
12.
[0041] Referring to FIG. 5C, the invention is illustrated fully
assembled with the top closure 38, 38' tightly screwed onto the
neck 12. During the tightening of the top closure 38, 38', the
flexible annular valve seal 56 contacts the horizontal portion 44
of the flange 50 and pushes or presses the flange 50 into the neck
12 until the lower surface of horizontal portion 44 contacts the
top of the neck 12. The material of the flexible annular valve seal
56 deforms slightly to form a sealing surface with the horizontal
surface 44. By forcibly pressing the larger flange 50 into the
inner diameter of the neck 12, the upper portion of the neck 12 is
pushed slightly outward and the radiused area 62 of the flange is
pushed slightly inward. In this manner, a tight seal is formed
between the flange 50 and the neck 12. This unique sealing feature
facilitates the use of the filter 10 of the present invention in
bottles 13 with necks 12 that vary slightly in size from standard
sizes and with top closures 38, 38' that have annular valve seals
56 at differing locations than that shown in FIG. 5A.
[0042] Although the invention includes other means of encasing and
directing flow through a filter tube, the preferred housing is
elongated to fit easily inside a narrow bottle neck. Additionally,
the preferred elongated design with radial flow through the tubular
filter element, provides a large surface area allowing lower flow
resistance for the water and resists clogging of the carbon filter
pores, which can be a concern with small pore sizes.
[0043] Manufacture of the filter housing 19 may be of any plastic
material such as, but not limited to, polypropylene or ABS, while
the filter tube 24 may be of powdered activated carbon which has
been formed into a solid but liquid porous carbon block through
compression or extrusion, or the tube may be formed through
sintering with a powdered polymer to create a liquid porous plastic
tube. The invented housing and filter tube design allow for a press
fit of the housing around the carbon block, which is preferred as
an easy and inexpensive assembly technique. Alternatively,
conventional assembly and connection methods may be used, such as
hot melt adhesives or spin welding.
[0044] In use in a plastic bottle neck, the filter 10 is inserted
into the bottle neck as shown in FIGS. 1-3 and as described above.
As the plastic bottle 13 is squeezed, water is purified as it is
forced through the filter tube. As the user releases the bottle, it
remembers its original shape and attempts to return to that shape.
In doing so, the bottle sucks in air from the atmosphere. The air
in this case passes through the center passage 36 and down to the
bottom of the filter housing body 20, where it exits through an
umbrella valve 70, preferably made of silicone, but it may also be
made of ethylene propylene (for example, "EPDM").
[0045] The umbrella valve 70 is a one-way valve that collapses flat
against the bottom surface of the filter housing body when the
bottle is squeezed, but opens easily as air pushes against it from
the opposite direction. Essentially, it opens the same way an
umbrella would inappropriately collapse if pointed away from the
wind. The use and position of this umbrella valve enables the
filter tube's matrix 24 to be made with a much tighter median pore
diameter (about 30-60 micron ranges) than it would if the path of
air return were through the filter tube itself (where about 80
micron median pore diameter or higher would be necessary). This is
because the pore diameter of the carbon tube would otherwise be
left more open since the air would not easily return through a pore
diameter much smaller than that. However, with the air-return path
being through the central passage 36 and the umbrella valve 70, the
pore diameter of the filter tube is able to be brought down to a
more preferred smaller range.
[0046] This tighter pore size has several advantages. First, it
creates a more tortuous pathway for the water, which in turn
provides increased contact between the water and the activated
carbon in the filter tube. The increased contact accelaerates the
chlorine and lead reduction adsorption processes. A second
advantage is the tighter pore diameter range creates a tortuous
pathway for water-borne parasites commonly found in municipally
treated tap water, for example, the Cryptosporidium, and Giardia
lamblia that are estimated to be in 39% of all U.S. tap water.
Thus, the invented filter also may be used to effectively reduce
water-borne parasites from municipally treated water.
[0047] Another advantage of the umbrella valve is that it quickly
returns air into the bottle so that the user is able to drink
rapidly without having to first wait for the air to return through
the filter and, second, to have to squeeze the water back into the
filter tube each and every time another drink is taken. Another
advantage of the umbrella valve 70 is that it puts less stress on
the bottle. As the bottle's memory returns it to its original
shape, it must work against any obstruction in the air pathway. If
the air were forced to return through the wall of the carbon block,
it would put greater stress on the plastic bottle.
[0048] The invented filter is intended to be a dual-use filter, and
includes a stem 72 protruding from the housing top 22 of filter
unit 10, for enabling the filter 10 to be attached to a drinking
straw and used in any open container for liquids such as, but not
limited to a cup, mug, or the common mug with a straw attached. In
use as a "loose" filter for purifying liquid in a non-bottle-shaped
container of liquid, the stem 72 or other straw attachment port of
the housing top 22 is pushed into the end of a typical high-density
polyethylene straw tube or alternatively a so-called memory straw
that is designed to bend and hold its shape. The stem 72 may fit
inside the straw tube or memory straw and hold it through
interference or friction thereby creating a watertight seal.
Alternatively, some flexible tubing has a smaller outside diameter.
In this case the stem 72 is designed in such a way to also receive
a smaller tube on the inside diameter of the same stem 72. This
inside diameter features a very slight draft so that as the tube is
pushed down into it, the draft increases the friction or
interference, thereby holding it even more firmly and making it
less likely to inadvertently come apart. The combined straw-filter
unit may be placed inside the container. This system works well in
a wide variety of containers, such as mugs 16 or cups 18. As the
user sucks on the straw water flows through the inlets 74 in the
housing body rather than through the housing body aperture 30. For
"air return," an open cup simply replaces the filtered liquid with
air from the atmosphere. Covered mugs, such as shown in FIG. 11,
typically provide their own air return through an opening in the
mug's cap. Other containers provide an adjustable plug, which can
be closed for transportation and opened for use. In any case, when
in use with a straw, the filter 10 may not need to provide for an
air return, and the umbrella valve 70 need not perform the role of
an air-return valve as it does in the bottle neck scenario.
[0049] The location of the valve 70 at the bottom of the filter is
well-suited for use with a straw tube, as it closes effectively
even when there is only a little liquid in the bottom of the cup or
mug. Also, because of the valve's location, it in no way obstructs
the use of the filter with the straw.
[0050] Thus, the invented filter may be interchangeably used either
installed in a bottle neck for squeezing of water through the
filter, or inserted with a straw into the bottom of a cup or mug
for sucking of water through the filter and the straw. No filter
found today has the advantages of being so universal that a
specific container is not needed. Empty plastic bottles are
everywhere, as well as mugs and containers using straws. Mug-style
containers are even given away at fast food restaurants to promote
the restaurant. Empty soda pop or mineral water bottles are
disposed of as trash. The invented filter may therefore become an
economical and easy-to-use accessory for making these containers
reusable and for making tap water a more desirable and pleasant
drink.
[0051] In either bottle-use or cup/mug use, the filter housing
serves several functions. It cosmetically covers the filter tube,
which is most often a black, carbonaceous material, protects it,
and provides a means for holding it in place in the bottle neck. In
addition, the filter housing also serves to define the water inlet
points and to direct water and air flow. The preferable placement
of the water inlets 74 is near the bottom of the housing body.
These perforations in the housing body are preferably elongated and
are spaced around the circumference of the body, but preferably
extend about 1/4-1/3 of the wall up the wall of the body. In this
way, when used in the bottom of a mug or cup, nearly all the liquid
may be sucked up through the straw. Also, in most bottles,
depending on the neck diameter and geometry, this water inlet 74 is
effective in emptying all but a small amount of liquid from the
bottle. The small amount left in the bottle may be described
generally as the volume between the bottle neck and the water
inlets 74, which remains in the bottle when the bottle is tipped up
for drinking.
[0052] Optionally, as shown in the filter 10' of FIG. 10, one or
more small slits 80 may be added to the housing 19 at or near the
top of the housing body 20, in order to allow complete or nearly
complete emptying of the bottle. One slit 80 of about 3/4 inch
length and about {fraction (1/32)}-{fraction (1/16)} inch width is
preferably located at the top of the body, and serves as an
additional water inlet near the top of the filter (in the neck,
which is the "bottom" of the bottle when the bottle is inverted for
finishing the drink). This single slit is sized and located to
drain that last amount of water, but is small enough that it does
not significantly interfere with use of the filter with a straw.
When in a cup or mug, little or no air passes through the slit 80
and through the carbon filter even when the liquid level is below
the slit 80, and so little or no effect of the slit 80 is noticed
in the straw application.
[0053] In alternate embodiments, shown in FIGS. 13 and 14 flanges
150 and 250, respectively, may further comprise a resilient
material to create a seal much like a rubber gasket. For use with a
geometry like flange 150 or 250 this seal may be made by a separate
gasket, or co-molded onto the flange 150 or 250 of the filter. The
resilient material is co-molded onto the flange and may be a
thermoplastic elastomer material such as by brands Kraton and
Sanoprene. As shown in FIG. 13 the resilient material 184 is shown
to reside only on the bottom surface 180 of horizontal portion 144
of flange 150 and not on the upper surface 182 of the horizontal
portion. Alternatively, the resilient material 284 could reside on
the upper surface 282 and the bottom surface 280 of horizontal
portion 244 of flange 250, as shown in FIG. 14.
[0054] The foregoing description is considered as illustrative only
of the principles of the invention. The words "comprise,"
"comprising," "include," "including," and "includes" when used in
this specification and in the following claims are intended to
specify the presence of one or more stated features, integers,
components, or steps, but they do not preclude the presence or
addition of one or more other features, integers, components,
steps, or groups thereof. Furthermore, since a number of
modifications and changes will readily occur to those skilled in
the art, it is not desired to limit the invention to the exact
construction and process shown described above. Accordingly, all
suitable modifications and equivalents may be resorted to falling
within the scope of the invention as defined by the claims which
follow.
* * * * *