Note: Descriptions are shown in the official language in which they were submitted.
FAUCET MOUNTED PURIFIER
BACKGROUND OF TEIE INVENTION
The purification of water by me~ns of ultraviolet radiation is well
known. In a conventional installation, water may pass through a pre-filter
5and then a reverse osmosis module. ~ollowing this, the water passes
through a carbon final filter, an ultraviolet irradistion unit, and then
through some pipin~ to a faucet.
While ultraviolet radiation is highly destruetive to bacteria, it has
been shown that under favorable circumstances, irradiated b~cteria can
10rep~ir themselves, given some time. Accordingly, water which has been
irradiated with ultr~violet radiation may show no bacterial growth upon
culturing immediately after irradiation, but later on the same water may
exhibit positive results on bacteria culturing. This particularly take place
by a process known as photo-reactivation, in which the bacteria are able to
15regain the cap~billty to multiply in the presence of visible spectrum light.
Accordingly, even in A system such as that described above in which
water passes through an ultraviolet irradiator, if the faucet is not used to
draw water continuously, bacteria can revive in the portion of piping which
is downstream from the irradiator, so that sta~nant water in the piping
20downstream from the irradiator can os-ce again become contaminated with
growing bacteria, without any extra bacteria being innoculated into the
stagnant water held in the faucet.
By this invention, a final ultraviolet irrsdiation step of very high
efficiency can be provided to a faucet which carries the unit of this
25invention, preferably in such a manner that water cannot be stored after
ultraviolet irradiation. To accomplish this~ the ultraviolet unit of this
invention may be designed to be at the ex~ct end of the water flow path.
The Galtek Corporation of Chaska, IViinnesota discloses an ultraviolet
sterilizing system in which ths faucet itself through which water flows is
30sterilized, particularly between uses, to prevent b~eteria from migrating
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upwardly into the faucet back toward the water source. The
prime purpose of the Galtek structure is to sterilize the
spout or aucet end, rather than to ster:ilize water passing
through the faucet.
By the present invention, an ultraviolet sterilizer
unit is provided, which exhibits improved efficiency for
sterilizing of water, and which may be mounted on the end of
the faucet to minimize or eliminate the chance that residual
water which has been ultraviolet irradiated will become
stagnant and reinfected with growing bacteria. The unit of
this invention may be activated by turning on the faucet and
deactivated by turning the faucet off, but time delay
devices and the like may be provided as desired to keep the
unit operating for a period of time after shut-off of the
faucet.
DESCRIPTION OF THE INVENTION
The invention in one aspect pertains to a water
purification unit adapted for connection to a faucet having
a distal outlet which unit comprises a housing defining an
inlet port and an outlet port, the housing including
ultraviolet-transmissive means and a flow passage between
the inlet port and the outlet port. An ultraviolet
radiation source is ~ositionedto irradiate the flow passage
through the ultraviolet transmission means and the flow
passage is configured to require the water to flow by the
ultraviolet radiation source at least twice to enhance the
ultraviolet irradiation of the water. Means are provided
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for connecting the inlet port of the housing to the distal
outlet end of a faucet so that there is no significant place
downstream of the housing outlet port for water to be
retained and to grow stagnant. Means other than the outlet
port is provided for draining the flow path when a faucet to
which the unit is connected is off.
More particularly there is provided a water
purification device which comprises a housing defin:ing an
inlet port, a labyrinth flow passage, and an outlet port,
where the flow passage communicates between the inlet and
outlet ports. The housing includes ultraviolet-transmissive
: means adjacent to ths labyrinth ~low passage.
An ultraviolet radiation source is positioned to
:irradiate the labyrinth flow passage through the
~ ultraviolet-transmissive means. In the illustrative
embodiment, means are provided for coupling the inlet port
of the unit to an outlet of a faucet.
Accordingly, as the faucet is turned on, water
enters the unit and passes through the labyrinth
flow passage, for significantly increased exposure times to
- ,ultraviolet radiation from the ultraviolet radiation source,
which is positionad to irradiate the labyrinth flow passage
- through the ultraviolet-transmissive means. The ultrav.iolet-
transmissive means may comprise a wall made of quartz,
for example, or any other desired ultraviolet-transmissive
material. The wall is exposed to the labyrinth flow
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passage which flows in a convoluted manner along the inner surface of the
ultraviolet transmissiYe wall, so that individuaI portions of the water are
exposed for an increased amount of time to ultraviolet radiation as they
pass through the labyrinth.
Since the unit of the present invention is mounted in direct
communication with an outlet of a faucet and the outlet port may be
immediately downstream from the labyrinth passage, no significant place
may be provided for water to be retained and to grow stagnant, giving
bacteria an opportunity to regain their capability of multiplying again
following ultraviolet irradiation.
It is generally preferred for drain hole means to be provided to the
labyrinth flow passage, so that when the faucet is shut off, water drains
from the passage to further elimlnate the possibility of bacterial regrowth
in stagnant water. In an embodiment in which drain hole means are
provided, the unit may be mounted at the base of the faucet instead of at
the faucet outlet, if desired.
Thé ultraviolet radiation source may preferably be a cylindrical
ultraviolet bulb backed by a parabolic reflector. The bulb and reflector
are positioned to provide ultraviolet radiation which mostly passes through
the ultraviolet-transmissive wall at substantially right angles thereto. Thus,
angular refraction of the ultraviolet radiation is avoided, increasing the
percentage of ultraviolet radiation which passes into the labyrinth, for more
efficient bacteriostatic effect.
As another advantage, the means for powering and operating the
ultraviolet bulb used In the unit of this invention may be positioned
remotely from the bulb and connected with an insulated wire, so that the
unit which is carried on the faucet may be small. The bulb powering
means, including typically a ~ transformer and ballast, may be placed
underneath the sink with which the faucet is associated, for example.
36~;
FUrtherlllOre, fl switch may be present to energize the ultrnviolet
bulb when the faucet is turned on and to turn the bulb off when the
faucet is turned off. Any desired timer device may be used to delay
switch shut off for a predetermined period of time after the faucet is
turned off. Additionfllly, another timer ma~ periodically cause the
ultraviolet bulb to be energized for regular9 intermittent irradiation of the
flow path for those times in which the f~ucet is not in active use.
The plane of the ultraviolet-trallsmissive wall may be generally
parallel to an axial line extending between the inlet and outlet ports. The
cylindrical ultravk)let bulb, backed by the parabolic reflector, may also be
positioned in parallel relation to the wall to cause ultraviolet radiation to
pass through the wall into the labyrinth.
Accordingly, an improved, faucet-mounted ultraviolet sterilization
unit is provided.
DESCRIPTION OF THE DRAWINGS
IN THE DRAWINGS:
F5G. 1 is an elevational view, taken partly schematically, of a
faucet, with the water purification unit of this invention attached;
FIG. 2 is an elevational view taken along line 2-2 of Fig. I;
FIG. 3 is A longitudinal sectional view taken along line 3-3 oï Fig.
l;
FIG. 4 is an elevational view taken along line 4-~ of Fig. 1;
FIG. 5 is an elevation~l view of another embodiment of a faucet,
with the water purification unit in this invention attaclled;
~5 FIG. 6 is a transverse sectional view taken along line 6-6 of Fig. 5; and
FIG. 7 is a reduced size partial, longitudinal sectional view of the
structure of Fig. 5, rot~ted 90 about its longitudinal axis.
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DESCRIPTION OF SPECIFIC EMBODIMENT
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Referring to the drawingsl a wflter purification unit in ~ceordance
with this invention is disclosed. Faucet 10 carries on its outer end
purification unit 12, either in permanent manner as shown where the unit
is part of the faucet, or by means of an attachmenl; means su~h as a
threaded nut or the like, so that the unit may be attached to conventional
faucets which are already ir~talled.
As shown particularly in Fig. 2, housing 14 defines inlet port 16,
outlet portion 18, and labyrinth flow passage 20, which may be a serpentine
or otherwise convoluted passage to increase the length of the flow path
exposed to ultraviolet radiation. Labyrinth flow passage 20 comrnunicates
between inlet 16 and outlet 18.
Housing 14 also cflrries w~ll 22, which m~y be mude of quartz or
any other uppropri~te ultraviolet transparent material. Quartz wall 22 may
cooperate with grooved wall 24, with the two members being sealed
together as shown in Fig. 3 to define the enclosed labyrinth 20.
Cylindrical ultraviolet bulb 26 is provided, being connected by wire
28 to a power source 30, which typically may include a transformer an~
ballast in conventional manner. The system is controlled by switch 32,
with switch 32 being connected if desired to the handle or other control
that permits water to flow through faucet 10. Thus, when water is flowing
through faucet 10, switch 32 is closed so that ultraviolet tube or bulb 26
is irradiating the water as it flows through labyrinth 20. When the faucet
is shut oîf, switch 32 may shut off ultraviolet bulb 26, orj if desired, a
timer may be provided so that the ultraviolet tube delays its shut off for a
predetermined length of time following shut off of fiow through the
faucet .
Ultraviolet bulb 26 may be backed by a parabolic reflector 34 that
extends the length of cylindrical ultraviolet bulb 26. Accordingly, light
that is emitted from bulb 26 may be refleeted off of parabolic reflector
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34, to travel in patlls indicated by arrows 36 to pass through wall 22 in
substantially perpendicular rnanner, for improved efficiency of ultraviolet
irradiation of labyrinth 20. This can be accomplished by placing ultraviolet
bulb 26 at the focus of parabolic (or elliptical) reflector 34 as shown.
It is typically deemed desirable to drain labyrinth 20 in between
use~s, so as to avoid the creation of a stagnant water area where irradiated
water rnay rest, with the possibility that bacteria will beg~n to multiply
again. To effect this, drain holes 38 may be provided at positions slightly
spaced from outlet port 18 for each convolution of labyrinth 20.
Accordingly, after use, when the faucet 10 is shut off, labyrinth 2û may be
drained by water flowing out of drain holes 38, to eliminate the stagnant
water problem.
The surfaces in which water flows in labyrinth 20 may be coated
with a hydrophobic agent such as polytetraJluoroethylene to facilitate the
draining of as much water as possible out of labyrinth 20 between uses.
Also, the water-contacting walls of labyrlnth 20 as formed in pl~te 24 may
be canted to increase the intensity of ultraviolet radiation on them, since
most of the ultraviolet radiation is approaching walls 22, 2~ in substantially
perpendicular relation to them.
As an alternative, a spherical source of ultraviolet radiation may be
mounted over a circular labyrinth and backed by a reflector.
Reierring to Figures 5 through 7, another embodiment of the
invention of this application is shown. Faucet lD in this înstance carries
on its outer end a purification unit 12a w~lich includes housing 14a defining
~5 inlet port 16a, outlet port 1&~, and labyrinth flow passage 20a. In this
instance, housing 14a provides a labyrinth flow passage 20a which is
arranged in a cylindrical configuration as shown about the axis ~0 of
housing 14a, with inlet port 16a and outlet port 18a being connected to
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djacent lengths 41, 43 of the convoluted or serpentine labyrinth flow
pflssage 20a. Accordingly, liquid in the flow passage follows the serpentine
path around the cylindrical plane as shown.
Within housing 1~ is fl cylinclrical wall 2~ of ultraviolet transparent
materials, for example, quartz. Within that, typically positioned in coaxial
relation with central axis 40, is a cylindricAI ultraviolet bulb 42 which may
irradiate most of the length of labyrinth flow passage 20a, for extended
irradiation of flu~ds passing therethrough. As with the Figure 2
embodiment, the Figures 5-7 embodiment may include drain holes defined
by labyrinth flow passage 20a to eliminate a stagnant water problem.
Connection wires 44 for the ultraviolet bulb 42 may pass out of
housing 14a as shown in Fig. 5, and be connected to a ballast and power
system in a manner analogous to the device of Fig. 1.
Alternatively, ultraviolet transparent wa~l 22a may be the outer
jacket of a cylindrical ultraviolet bulb, if desired.
Accordingly, the invention of this application provides a ultraviolet
irradiation system which is carried on the end of a faucet, making use of a
labyrinth system and a ultraviolet bulb with reflector to provide greater
irradiation of fluids passing through the labyrinth. The risk of reactivation
of bacteria which have been previously irradiated is greatly reduced, when
compared with conventional systems, by the invention of this applicstion.
The above has been offered for i}lustrative purposes only, and is not
intended to limit the scope of the invention~ which is as defined in the
clai ms below .
