Note: Descriptions are shown in the official language in which they were submitted.
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Multiple Barrier Filter Apparatus
Technical Field
The present invention relates generally to filtering systems and in particular
to
a filtering apparatus that includes multiple filtering elements.
Background of the Invention
For at least the last 15 years, there have been several configurations of
"under-sink" reverse osmosis (RO) systems designed to improve the quality of a
io relatively small amount of water to be used for drinking and cooking by a
homeowner. A few examples of such systems are described in US patents
4,650,586 and 4,629,568 both of which are owned by the assignee of the present
invention and incorporated herein by reference.
An objective of typical under sink reverse osmosis systems is to decrease the
is total dissolved solids (TDS) of the supplied city or well water and thereby
improve
the taste, odor or chemical makeup of the water. These under the sink reverse
osmosis systems can be upgraded to include additional unit processes to pre-
treat
the incoming water for chlorine or sediment removal prior to the RO unit. This
pre-
treatment improves the operation and prolongs the life of the RO membrane. In
2o addition pre-treatment further polishes the water produced by the RO
membrane to
remove both trace organics that might cause taste issues and small molecular
weight contaminants that might pass through or be poorly rejected by the RO
membrane. Therefore today there are many versions of RO units that effectively
remove or reduce specific unwanted ionic contaminants and or organics to
improve
2s the quality of the water for the use of the homeowner.
There is increasing concern that some of the water supplies, both from wells,
surface waters or even municipalities may, from time to time contain unwanted
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microbiological contaminants such as pathogens, that may be harmful when
ingested by people, especially persons with immune system deficiencies.
While the pore size of the common RO membrane is sufficiently small to
prevent the passing of microbiological contaminants, testing over the years
has
s shown that the RO unit alone cannot consistently meet the relatively
stringent
requirements to be classified a "microbiological purifier" as defined in EPA
in the
"Guide Standard and Protocol for Testing Microbiological Water Purifiers"
(1987
revision). It is believed that the reason for this is the imperfections in the
RO
membrane itself or in the methods of bonding the membrane together at the ends
of
io the assemblies. While there are several methods available to deal with such
concerns, such as boiling the water for several minutes or adding anti-
pathogen
agents like iodine to the water, most of these are not convenient and/or may
make
the water less pleasant to drink. Ultraviolet light filters that neutralize
contaminants
by exposure to certain wavelengths of light are also known in the art. These
filters
is suffer from several practical drawbacks including the fact that they rely
on electricity
to function and also require relatively complex controls to ensure that water
is not
overheated due to extended exposure to the light.
Summary of the Invention
2o By adding multiple barrier filter capabilities to a traditional under sink
RO unit,
improved removal of microbiological contaminants, unwanted ionic species, and
organics can be achieved.
According to the present invention a filter apparatus for treating water
containing particulate or microbial contaminants is provided. The filter
apparatus
2s includes a first filter element disposed within a first sealed outer
housing and in fluid
communication with a first inlet port and a first outlet port. The first
filter element is
capable of treating water at a first flow rate and is adapted to remove
contaminants
that are larger than a first contaminant size. A second filter element is
disposed
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downstream of the first filter element in fluid communication with a second
inlet port
and a second outlet port. The second filter element is capable of treating
water at a
second flow rate higher than the first flow rate and is adapted to remove
contaminants that are larger than a second contaminant size. An accumulating
s vessel is placed in fluid communication with the first outlet port and the
second inlet
port for storing water that has been treated by the first filter element prior
to
treatment by the second filter element.
For a preferred embodiment that is directed to removing microbial
contaminants, the first filter element is a virus filter membrane capable of
removing
io contaminants larger than 0.01 micron and the second filter element is a
bacteria
filter membrane capable of removing contaminants larger than 0.1 micron.
In an exemplary embodiment that facilitates under sink mounting, the second
filter element is disposed within the first sealed outer housing. According to
a
feature, at least one of the first and second filter elements is generally
cylindrical in
is shape and has a central void and the water flowing to and from the other of
the first
and second filter element flows within the central void. According to another
feature,
the first inlet port, first outlet port, second inlet port, and second outlet
port are
disposed on a single surface of the sealed outer housing. According to yet
another
feature, a flow limiting device is place in fluid communication with the first
filter
2o element for controlling the flow of water to the first filter element.
According to an embodiment a pre-treatment filter is placed in fluid
communication with the first inlet port for removing relatively large
contaminants
prior to treatment by the first and second filter elements. According to an
embodiment, a post filter is placed in fluid communication with the
accumulating
2s vessel and adapted to remove contaminants that originate in the
accumulating
vessel or may have passed through prior filters. In an embodiment, a cross
flow
membrane filter, such as a reverse osmosis filter, is placed in fluid
communication
with the first inlet port. In a preferred embodiment, a check valve is placed
on a
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concentrate line of the cross flow membrane filter.
In an exemplary embodiment, a flow monitor is placed in fluid communication
with the first outlet port to monitor an amount of water that has been treated
by the
filter apparatus. According to a feature, the flow monitor is operable to
discontinue
s the flow of water through the filter apparatus when a predetermined amount
of water
has been treated by the filter apparatus. In one embodiment, the flow monitor
is
part of the post filter.
In a preferred embodiment, the filter apparatus includes a check valve in
fluid
communication with the second outlet port and downstream of the second filter
to element for preventing backflow of contaminated water into the filter
apparatus.
According to a feature of the invention, the check valve is a duck bill check
valve
installed in a treated water dispensing faucet in fluid communication with the
second
outlet port and through which treated water flows out of the filter apparatus.
According to another feature the check is made of an antimicrobial material.
is Another exemplary embodiment of the inventive filter apparatus is adapted
to
treating water containing microbial contaminants. A viral membrane filter is
disposed within a first sealed outer housing and in fluid communication with a
first
set of inlet and outlet ports. The viral membrane filter is adapted to remove
viral
contaminants. A bacterial filter membrane is disposed downstream of the viral
2o membrane and in fluid communication with a second set of inlet and outlet
ports, the
bacterial filter membrane adapted to remove contaminants.
In an embodiment that facilitates under sink mounting, the bacterial filter
element is disposed within the first sealed outer housing. According to a
feature, at
least one of the viral and bacterial filter membranes is generally cylindrical
in shape
2s and has a central void such that water flowing to and from the other of the
viral and
bacterial filter membrane flows within the central void. According to another
feature,
the first inlet port, first outlet port, second inlet port, and second outlet
port are
disposed on a single surface of the sealed outer housing.
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According to an embodiment a pre-treatment filter is placed in fluid
communication with the first inlet port for removing relatively large
contaminants
prior to treatment by the first and second filter elements. According to an
embodiment, an accumulating vessel is placed in fluid communication with the
first
s outlet port to store water that has been treated by the viral filter
membrane prior to
being treated by the bacterial filter membrane. According to a feature a post
filter is
placed in fluid communication with the accumulating vessel and adapted to
remove
contaminants that originate in the accumulating vessel or pass through prior
filters.
In an embodiment, a cross flow membrane filter is placed in fluid
communication
io with the first inlet port.
In an exemplary embodiment, a flow monitor is placed in fluid communication
with the first outlet port to monitor an amount of water that has been treated
by the
filter apparatus. According to a feature, the flow monitor is operable to
discontinue
the flow of water through the filter apparatus when a predetermined amount of
water
is has been treated by the filter apparatus. In one embodiment, the flow
monitor is
part of the post filter.
In a preferred embodiment, the filter apparatus includes a check valve in
fluid
communication with the second outlet port and downstream of the second filter
element for preventing backflow of contaminated water into the filter
apparatus.
2o According to a feature of the invention, the check valve is a duck bill
check valve
installed in a treated water dispensing faucet in fluid communication with the
second
outlet port and through which treated water flows out of the filter apparatus.
According to another feature the check is made of an antimicrobial material.
According to a preferred embodiment, a filter apparatus for removing
2s contaminants from water containing microbial contaminants includes a cross
flow
membrane filter for removing a significant amount of relatively large
contaminants
from the water. A viral membrane filter is disposed within a first sealed
outer
housing and in fluid communication with cross flow membrane filter that is
adapted
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to remove viral contaminants and a bacterial membrane filter is in fluid
communication with the viral membrane filter that is adapted to remove
bacterial
contaminants. According to a feature of this embodiment, the cross flow
membrane
filter is a reverse osmosis filter. An additional feature is an accumulating
vessel
disposed between and in fluid communication with the viral membrane filter and
the
bacterial membrane filter for storing water that has been treated by the viral
membrane. Preferably, the bacterial membrane filter is disposed in the first
sealed
outer housing and at least one of the viral and bacterial filter membranes is
generally
cylindrical in shape and has a central void and such that water flowing to and
from
io the other of the viral and bacterial filter membrane flows within the
central void.
According to an embodiment of the invention, a treated water dispensing
faucet for dispensing water that has been treated to remove contaminants
includes
a conduit for directing the flow of treated water from a filtration system to
a
dispensing station. The conduit has a first end connected to the filtration
system
is and a second end that includes an orifice that opens to the dispensing
station. A
check valve is mounted to the second end for preventing the back flow of
contaminants to the filtration system. According to a feature, the check valve
is a
duck bill check valve that includes antimicrobial material. According to yet
another
feature, a valve shield member substantially encloses the check valve for
preventing
2o contact between foreign objects and the check valve.
According to another feature of the invention, a filter cartridge is disclosed
that includes a housing that defines first and second isolated regions within
the
housing. The first region includes a first filter and a flow path extending
from a first
inlet to a first outlet. The second region defines a flow path extending
between a
2s second inlet port and a second outlet port. The ports are arranged in a
substantially
linear, side-by-side relationship and are adapted to establish fluid
connections
between the filter cartridge and a manifold forming part of a water treatment
system
as the filter cartridge is installed into its operative position. In the
preferred
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embodiment, the first region includes a viral filter and the second region
includes a
bacterial filter.
Although the construction illustrated in the preferred embodiment includes a
viral filter and a bacterial filter located in the same replaceable housing,
it should be
s understood that aspects of this invention can be applied to systems in which
separate viral and bacterial filter units are utilized, as opposed to having
both filters
in one housing.
These and other objects, advantages, and features of the invention will be
better understood from the accompanying detailed description of preferred
io embodiments of the invention when reviewed in conjunction with the
accompanying
drawings.
Brief Description of the Drawinas
The present invention is illustrated by way of example and not limitation in
the
is figures of the accompanying drawings, in which:
Figure 1 is a schematic representation of a water filtration system
constructed
in accordance with the present invention;
Figure 2 is a front plan view of a water filtration system depicted in Figure
1;
Figure 3 is a cross section view of a water dispensing faucet in accordance
2o with a feature of the present invention;
Figure 4 is a cross section of a multiple barrier microbial filter of the
water
filtration system shown in Figure 2;
Figure 5 is a cross section of a multiple barrier anti-microbial filter of the
water
filtration system shown in Figure 2 and as seen from the plane indicated by
the line
2s 5-5 in Figure 2;
Figure 6 is an exploded view of the multiple barrier anti-microbial filter;
Figure 7 is another sectional view of the anti-microbial filter substantially
similar to the cross section shown in Figure 4, but showing the filter
detached from
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the water filtration system;
Figure 8 is an exploded view of the water filtration system shown in Figure 2;
Figure 9 is a perspective view of a manifold that forms part of the water
filtration system;
s Figure 10 is a partially schematic representation showing a bottom
elevational
view of the manifold shown in Figure 9 and also illustrating fluid connections
between a storage tank and faucet;
Figure 11 is a top plan view of the manifold shown in Figure 9;
Figure 12 is a sectional view of the manifold as seen from the plane indicated
io by the line 12-12 in Figure 11;
Figure 13 is a fragmentary sectional view of the manifold as seen from the
plane indicated by the line 13-13 in Figure 10; and,
Figure 14 is a top elevational view of a locking handle.
is Detailed Description of the Preferred Embodiment
Figure 1 illustrates schematically a water treatment system 10 for removing
particulate and microbial contaminants from water. The water treatment system
10
designed for mounting under the sink in a typical residential kitchen and for
dispensing treated water from a system dedicated faucet 70 including a flow
control
Zo valve 71 having an operating handle 71 a. The system includes a pre-filter
20 such
as Kinetico part number 9309 and a reverse osmosis filter 30 (such as that
disclosed
in U.S. patent number 4,650,586, assigned to assignee of the present invention
and
incorporated herein by reference) placed in series to remove a majority of
contaminants typically found in residential water supplies. While an RO filter
is
2s described herein, it will be apparent to one of skill in the art that any
cross flow
membrane filter such as a nanofiltration unit, an ultrafiltration unit, or a
microfiltration
unit can be used to practice the present invention. The pre-filter 20 filters
out
entrained solids to reduce the incidence of plugging of the internal membrane
(not
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shown) in the reverse osmosis filter 30 and is believed to prolong the life of
the
reverse osmosis filter. A check valve 79 on the concentrate line of the RO
filter
prevents entry of contaminants into the system via the concentrate line.
A multiple barrier microbial filtration unit 40 that includes a viral filter
s membrane 40a and a bacterial membrane 40b polishes the water that exits the
reverse osmosis filter 40 to remove microbial pathogens from the water. The RO
filter 30 removes a large percentage of the contaminants that remain in the
water
after treatment by the pre-filter 20 to prevent clogging of the relatively
fine pores
found in the viral and bacterial membrane filters 40a, 40b. In addition, the
RO filter
io serves as a flow limiting device that controls the flow to the viral
membrane filter 40a
thereby facilitating operation of the viral filter membrane at a sufficiently
slow flow
rate that optimizes contaminant removal based on a relatively small filter
membrane
size.
A storage tank 50 such as is placed in fluid communication with an outlet of
is the viral membrane 40a to store water that has been treated by the viral
membrane.
The placement of the storage tank 50 after the viral membrane 40a, but before
the
bacterial membrane 40b, improves the flow capacity of the overall system. This
is
because the flow capacity of the viral filter membrane 40a is significantly
lower than
the desired flow rate for the faucet 70. The flow capacity of the bacterial
membrane
20 40b is higher than that of the viral membrane and as such, water can be
pulled from
the storage tank 50 on demand by the faucet and be treated by the bacterial
membrane 40b to filter out contaminants originating from the storage tank or
have
passed through prior filters at a flow rate that is acceptable in terms of
providing flow
at the faucet. The bacterial membrane 40b also serves as a protection against
zs bacterial contamination that may enter the system at the faucet 70. A post
filter 60,
such as the one disclosed in U.S. patent number 4,698,164 assigned to the
assignee of the present invention and incorporated herein by reference, is
positioned between the viral membrane 40a and the bacterial membrane 40b to
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provide an additional filter to protect against contaminants that originate in
the
storage tank or have passed through prior filters. In addition, the post
filter 60
serves as a fluid monitor by monitoring the amount of water flowing to the
anti-
bacteria membrane 40b and shutting off flow via an internal flow control
mechanism
s (not shown) once a predetermined amount of water has been treated. This shut
off
feature prevents system usage once the filter element performance has degraded
to
an unacceptable level.
Figure 2 is a front plan view of a water treatment system 10. A mounting
bracket 12 with mounting tabs 14 for connecting the bracket under a typical
io residential sink supports a manifold assembly 13. The manifold assembly 13
includes water conduit and connection points for replaceable cartridge
portions of
the various filter units that make up the system: the pre-filter 20, the
reverse osmosis
filter 30, the multiple barrier microbial filtration unit 40, and the post
filter 60 having a
flow monitoring head 61 that gives an indication of the amount of water that
has
is been treated by the current cartridge and shuts of flow when a
predetermined
amount of water has been treated. An outlet connection (to be described) is
connected to a line 314 that runs to the faucet 70 (shown in Figures 1, 3 and
10).
While this particular combination of pre-filter, reverse osmosis filter, and
post filter is
discussed for the purposes of this description, other combinations of filters
that may
20 or may not include these filters may be used in conjunction with the
multiple barrier
microbial filtration unit in the practice of the present invention.
Referring now to Figure 3, a cross sectional view of the faucet 70 is shown. A
water conduit or spout 72 terminates at one end in a dispensing orifice 74. A
check
valve 75 such as a duck bill check valve supplied by Vernay Laboratories, Inc.
of
2s Yellow Springs, Ohio as part number VA 4295 is held adjacent to the
dispensing
orifice 74 by a protective shield or spout tip 78 that encloses the check
valve 75 and
is pressed or threaded onto the water conduit 72. Due to the presence of
bacterial
contaminants in the kitchen and bathroom sinks to which the faucet is mounted,
it is
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beneficial to employ this check valve to protect the system from contaminants
in the
air, splashes, or objects found in the sink. To further enhance the
contamination
reducing capability of the system, the check valve 75 may be molded of a
material
that includes an antimicrobial treatment. The check valve 79 (Figure 1 ) on
the
s concentrate line may be a similar duck bill type valve appropriately sized
for the
concentrate line. Alternately, conventional ball-type check valves may be
used.
Multiple Barrier Microbial Filtration Unit
Figure 4 illustrates details of the multiple barrier microbial filtration unit
40 that
io filters microbial contaminants from the water. The microbial filtration
unit 40 is
connected to an associated manifold portion 15 that forms part of the manifold
assembly 13, with screws, tabs, or other appropriate means. The manifold 15
provides appropriate fluid paths to route the water into and out of the
various
components of the microbial filtration unit 40. The internal workings of the
manifold
is 15 will be further explained below. An inlet 41 defined by the manifold 41
routes
water from the reverse osmosis filter 30 to the microbial filtration unit 40
via a first
input port 110 that is in fluid communication with the microbial filtration
unit 40
The microbial filtration unit 40 includes a sealed outer housing indicated
generally as 45 having an end cap 43 that is welded to the housing after
assembly
20 of the filter elements 40a and 40b therein. It is believed that enclosing
the viral filter
membrane 40a and the bacterial filter membrane 40b in a single cartridge
eliminates
overall system performance variations that might be caused by housing the
filter
membranes separately and in addition the single cartridge facilitates removal
and
replacement by the end user. The viral filter membrane 40a engages the end cap
2s 43 to locate the element such that first fluid channel 114 is defined
between the
inner wall of the housing and the outer surface of the membrane 40a. The viral
filter
membrane 40a is cylindrical in shape and includes a pleated membrane filter
element disposed concentrically about a tubular supporting structure and
encased in
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an outer protective jacket having fluid access openings therein. Filters such
as the
viral filter membrane are known in the art. An example of the viral filter 40a
is
manufactured by Pall Corporation of New York under part number VABV20POA.
The viral filter membrane 40a engages and sits upon an interior connector 44
having
s a fluid path (to be described in connection with Figure 6) for incoming
water to enter
into the first fluid channel 114 through a first inlet port 110 and through a
first inlet
conduit 112. The water flows to a first interior filter channel 115 by passing
through
the filter membrane 40a to remove contaminants and treated, outgoing water
exits
the viral filter membrane 40a through a first outlet conduit 116 that is
connected to
io the manifold 15 by a first outlet port 118. O rings 135, 131 seal the
interface
between the viral filter membrane 40a and the interior connector 44, and the
interior
connecter 44 and the outer housing 45, respectively.
The manifold 15 provides a fluid path from the first outlet port to both the
storage tank 50 (Figure 1 ) and the bacterial filter 40b such that water will
flow to the
is storage tank unless the tank is empty and there is a demand for water at
the faucet
70. In this case, the water from the viral filter membrane 40a will travel
directly to
the post filter 60 and on to the bacterial filter 40b as described in further
detail
below. The storage tank enhances the overall output capability of the system
because it buffers the flow reducing effect of the small pore size needed to
filter out
2o small, virus sized particles removed by the viral filter membrane 40a.
The post filter 60 (Figures 1 and 2) includes a carbon filter (not shown) that
removes contaminants from the water that may be have passed through the prior
filters or are a result of the environment of the storage tank. In addition,
as already
described, the post filter serves as a fluid monitor to shut off flow through
the system
2s once a predetermined quantity of water has been treated. Replacement of the
cartridge on the post filter resets the monitor so that flow can be
reestablished.
Referring again to Figure 4, the bacterial filter membrane 40b is cylindrical
in
shape and includes a pleated membrane filter element disposed concentrically
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about a tubular supporting structure and encased in an outer protective jacket
having fluid access openings therein. Filters such as the bacterial filter
membrane
are known in the art. An example of this type of filter is manufactured by
Pall
Corporation of New York under part number NA7AAOOPOA. The bacterial filter
s membrane 40b engages the interior manifold 44 to locate the membrane and
form a
second fluid channel 121 through which water can flow from a second inlet port
127
and through the bacterial filter membrane 40b to a second outlet channel 122
that is
in fluid communication with a second outlet port 130. The outlet port 130
connects
to the manifold 15 which provides a connection to the faucet 70.
to As can be seen from the foregoing description, by providing multiple
barrier
microbial filtering capabilities in conjunction with a cross flow membrane
filter, a
filtration system capable of significantly reducing microbial contaminants
from water
can be provided in a unit sized to fit beneath a residential sink.
Figures 6 - 14 illustrate other features and constructional details of the
is present invention. In the preferred embodiment, the multiple barrier
filtration unit 40
is configured as a replaceable cartridge. Referring, in particular, to Figure
6, the
filtration unit 40 includes the outer housing 45 (previously described) that
is closed at
its bottom end by the end cap 43. An assembly of components is captured within
the housing 45 and end cap 43. The components include the viral and bacterial
2o filter units 40b, 40a (previously described). The upper part of the viral
filter 40b is
secured to an adapter 200 which defines three upwardly directed sockets 202,
204,
206. Referring also to Figure 7, these three sockets sealingly engage nipples
202a,
204a, 206a which depend downwardly and are integrally formed with a top 45a of
the housing 45. Associated O-rings 207 (Figure 6) seal the interface between
the
2s sockets and nipples.
Referring to Figures 4-7, a water receiving or inlet chamber 219 is defined
between the top of the adapter 200 and the underside of the cartridge housing.
As
seen best in Figure 7, the inlet port 250a communicates with the inlet chamber
219.
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Water to be treated is received in the chamber 219 and travels to the second
fluid
channel 121 via slots 200a (shown in Figure 6) formed in the adapter 200.
As described above, the bottom of the viral filter 40b sits on the connector
44. The connector includes an upstanding, integrally molded pipe assembly 220a
s that defines the fluid passages 112, 116 (see also Figure 4). A rigidizing
rib 221 is
molded between the pipe structure. A pair of nipples 206b, 204b sealingly
engage
the sockets 204, 206 defined in the cap 200. Associated O-rings 222 seal the
interface between the nipples and sockets. Also integrally formed in the
connector
220 is a cross passage 230 which communicates the passage 112 (defined by the
io pipe assembly 220a) with the region 114 (see also Figure 4) that surrounds
the viral
filter 40a. The communication is indicated by the dashed line 230a in Figure
7. In
particular, the cross passage 230 communicates the channel 112 with the
outside of
a downwardly depending flange 220c forming part of the connector 220. The
outside of the flange 220c communicates with the region 114, i.e., the outside
of the
is viral filter 40a.
The bottom of the viral filter 40a sits on a filter spacer 234 which, in turn,
fits
within and sealingly engages the bottom cover 43 of the filter housing.
Turning now
to Figure 7, the filter unit 40 is configured to be relatively easily
replaceable without
the need for special tools. As previously described, the water treatment
system
2o includes a mounting bracket 12 to which the fluid manifold 15 is secured.
In
particular and referring also to Figure 8, the manifold 15 includes mounting
apertures 15a through which fasteners extend in order to bolt the manifold to
the
underside of the bracket 12 by means of mounting holes 15b. The manifold
portion
15 defines internal fluid passages for communicating the internal fluid paths
defined
2s by the filter unit 40 with other components of the system. In particular,
and referring
to Figures 7 and 9, the manifold 15 defines four downwardly depending nipples
250,
252, 254 and 256. The cartridge housing 45 defines four corresponding sockets
250a, 252a, 254a and 256a which are configured to receive and sealingly engage
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the associated manifold nipples 250, 252, 254, 256. The sockets 252a, 254a,
256a
connect to and may form part of the nipples 202a, 204a, 206a, respectively.
The
housing sockets include associated O-rings 260 and pressed-in retainers 262
for
holding the O-rings within the sockets 250a, 252a, 254a, 256a shown in Figure
7).
s The housing 45 also includes integrally molded upstanding, retaining lugs
270, as well as a pair of stabilizing standoffs 272. The standoffs 272 include
reduced diameter portions 272a at their upper ends. To install the cartridge,
the
cartridge is positioned beneath the supporting bracket 12 and attached
manifold 15.
By raising the cartridge upwardly, towards the bracket, the four depending
nipples
io 250, 252, 254, 254 of the manifold 15 enter the associated sockets 250a,
252a,
254a, 256a while concurrently, the upwardly extending lugs 270 enter and
extend
through complementally shaped holes 270a formed in the bracket 12. In
addition,
the standoffs 272 engage the underside of the bracket 12 with the reduced
diameter
portions 272a extending into complementally shaped holes 273 formed in the
is bracket 12 (see Figure 8).
To secure the filter unit 40 to the bracket 12, a molded retainer clip 280 is
removably secured to the lugs 270. The detailed construction of the retainer
clip
280 is shown in Figure 14. In particular, each lug 270 includes an aperture
281 near
its upper end (shown in Figure 7). The retaining clip 280 includes a pair of
spaced
2o apart, split pins 280a molded integrally with a handle-like portion 280b.
The split
pins 280a, in their relaxed state, define a diameter greater than the diameter
of the
holes 281 and are compressed as they are inserted into the lugs 270. The pins
280a include detents or protrusions 283 which engage the rear surface of the
lugs
270 and inhibit withdrawal of the retainer 280.
zs As the manifold nipples 250, 252, 254, 256 enter the cartridge sockets
250a,
252a, 254a, 256a, they are sealingly engaged by the associated O-rings 260
located
within the sockets and, thus, fluid leakage between the nipples and the
sockets is
inhibited while still providing a releasable, fluid connection.
is
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Figure 10 illustrates an exploded view of the water treatment system and, in
particular, shows the various filter units and the manifold assembly 13 and
bracket
12 to which the filter units are releasably attached. A cover 290 preferably
overlies
the bracket 12 and hides from view the top of the bracket and the fluid
connections,
s manifold and retainers for the filter units and cartridges.
Referring to Figures 9-13, the construction of the manifold portion or segment
15 (to which the filter unit 40 is attached) is illustrated. In particular,
Figure 10, which
is a view of the underside of the manifold 15, illustrates schematically the
fluid flow
paths defined by the manifold 15 along with the connections to the storage
tank 50
to and faucet 70. The manifold 15 includes a conduit segment 300 which
includes a
pair of O-ring grooves 300a adapted to receive suitable O-rings. The conduit
segment 300 is adapted to be received in an input or inlet socket of the
filter 60. A
socket-like connection 302 is adapted to receive a conduit that connects the
socket
302 with the output of the filter unit 60. Another socket-like connection 304
forms
is part of the manifold 15 and is adapted to sealingly connect to a nipple
which defines
an output from the RO filter unit 30. The manifold 15 also defines a pair of
conduit
connections 310, 312. The conduit connection 310 is intended to connect with a
conduit that connects the tank 50 with the manifold 15. The connector 312
connects
the manifold 15 with a feed conduit 314 (see Figure 1 and 10) for the faucet
70.
2o As seen best in Figure 10, the passages 330, 332 and 338 are at least
partially formed by tubular segments 316a, 316b, 316c, 316d. During
manufacture
of the manifold 15, the right ends (as viewed in Figure 10) of the tubular
segments
are sealed. In the illustrated embodiment, a blocking plate 318 is suitably
secured to
the right ends of the tubular segments 316a, 316b, 316c, 316c using
conventional
2s attachment methods, such as welding or adhesively bonding.
The nipple 250, which serves as an input to the bacterial filter 40b, is
connected to the socket 302 by a passage defined by the manifold and
illustrated
schematically by the dashed line 330.
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The nipple 256, which communicates the output from the viral filter 40a with
the storage tank 50 and with the input to the post filter 60 is connected to
the conduit
connector 310 and the conduit segment 300 by communicating internal passages
332a, 332b . With this configuration, a significant amount of water can be
stored by
s the tank 50, rather than only processing water as it is dispensed by the
faucet 70.
The nipple 254, which communicates filtered water from the RO unit 30 to the
input side of the viral filter 40a, is connected to the socket 304 by an
internal
passage 336. The nipple 252, which is connected to the output side of the
bacterial
filter 40b, communicates with the conduit connector 312 by an internal passage
338.
io As noted above, the conduit connector 312 is connected to a feed conduit
314 for
the faucet 70.
Figures 12 and 13 illustrate additional details of the passages molded within
the manifold 15 which are illustrated schematically in Figure 10. It should be
understood, however, that alternate configurations for the manifold portion
15, as
is well as the passages molded within the manifold, can be made while still
providing
the fluid connections and functions of the illustrated embodiment and are,
therefore,
contemplated by the present invention.
In the preferred embodiment, the retaining lugs 270 are disposed in a parallel
relationship and are rectangular in cross-section. The standoffs 280 are
located in a
Zo spaced apart relationship and are disposed at a 12:00 and 6:00 position
with respect
to the lugs 270 which are located at a 9:00 and 3:00 position. In the
preferred and
illustrated embodiment, the sockets 250a, 252a, 254a, 256a formed in the
housing
45 which receive the nipples 250, 252, 254, 256 are located in a juxtaposed
positions and have mutually parallel axes. It should be understood, however,
that
2s the positioning of the lugs 270, standoffs 272 and sockets 250a, 252a,
254a, 256a
may be changed without substantially changing their functional purposes. The
sockets 250a, 252a, 254a, 256a may, for example, be spatially oriented on the
top
of the cartridge housing 45 and be adapted to engage similarly spaced manifold
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nipples.
It should also be noted that the water treatment system illustrated in the
drawings is sized for residential use. It should be understood, however, that
the
principles of this invention can be applied to much larger water treatment
systems
s that could be put to commercial uses. Those skilled in the art would
recognize that
larger filter units and conduits would be needed in order to sustain the types
of flow
rates that would be required for commercial applications.
Although the present invention has been described with a degree of
particularity, it is the intent that the invention include all modifications
and alterations
io from the disclosed design falling within the spirit or scope of the
appended claims.
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