Note: Descriptions are shown in the official language in which they were submitted.
t3~7~
~EVICE FOR WATER PURIFICATION
The present invention concerns a device for water
purification with a container, which comprises on the
outside an approximately cylindrical wall with cover
and bottom, and in which spirally arranged partitions
are mounted.
A filter tank for water purification of the above-
described type with a jacket and with a funnel mounted
on the said jacket for mounting on vessels is already
known from German Design Patent No. 73 46 108. This
device is bipartite, namely consisting of the funnel
and the jacket, with the funnel being tightly connected
with the approximately cylindrical jacket across a
flange. The outside diameter of the jacket is
considerably smaller than that of the funnel. The
jacket has inserted screens both at the bottom, serving
at that point as a bottom, and at the top, and the
cleansing agent is held in the space between the said
screens.
During the use of this known purification device,
mostly in households, fresh water is filed from the
water pipe into the funnel at the top, and it runs
through the bed of filter material due to its own
weight, i.e., under the pressure of the water column;
the height of the bed is predetermined by the length of
the jacket. Since only the weight of the water to be
purified itself, which is to generate the passage
pressure is predetermined, the flow velocity of the
liquid across the packing is sufficiently low so that
there is an adequate hold time, and thus the water is
purified thoroughly until the purified water leaves the
jacket at the bottom through the screen.
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If one should wish to increase the flow rate or to
improve the quality of purification, one would have to
preset a longer contact time ~etween the pac~ing and
the liquid to be purified. However, the contact time
becomes shorter as the flow velocity increases, unless
the height of the bed is increased. In the known case
this implies an elongation.of the jacket. Devices with
an excessively long jacket are normally undesirable.
Especially in households and in catering institutions,
water purification is considered a necessary evil, and
one is rather reluctant to install bulky devices for
this purpose. On the other hand, one is dependent upon
the purification, especially on the demineralization,
of water, which is determined by the type of the
packing, e.g., activated carbon or ion exchangers or a
mixture of both. Thus, very thorough purification and,
possibly separating or combined, a decarbonization of
the water are also possible. It is known that the
quality of the filtered or demineralized water is
strongly dependent on the height of the filter bed.
However, as was mentioned above, a great height of the
filter bed in the form of a long, slender column
requires much space and is difficult to fit in.
Therefore, the present invention has the basic
task of improving a water purification device of the
above-mentioned type in such a way that a great bed
height is provided without excessive space requirement,
so that such devices will be used as willingly as
possible in households, catering establishments, or
industrial practice.
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This goal is achieved according to the present
invention in that the container can be filled with
cleansing agent, and that one screen each is mounted at
its inlet and outlet, so that a long bed height is
obtained for the cleansing agent. The above-mentioned
spiral form is not restricted to the geometrically
ideal spiral, because instead the spiral can have an
approximately oval, elongated, or rectangular course
with rounded corners, and the shape- of the container
can range from round to angular. Due to the spiral
arrangement of the partitions inside the container,
spiral pipes are provided accordingly, so that a long
bed height is obtained in a narrow space for a filter
packing, when the packing for the purification of the
water, preferably activated carbon or ion exchanger, or
a mixture of the two, is filled in between the
partitions, namely, into the pipes formed by the
partitions. Consequently, without the device becoming
too unwieldy, it is possible to maintain the water
being purified in contact with the packing over a long
path from the inlet to the outlet. Thus, either an
extremely high quality of purification is achieved, or
the flow velocity can be increased with still very qood
water quality. Specifically, the device according to
the present invention can be attached to a faucet by
means of a cooperating coupling at the inlet, so that
it is possible to operate under such a water pressure
as normally occurs in the water mains. This pressure
is up to six bars of mercury. The bed height is
determined, of course, by the length of the section or
pipe packed with filter material, through which the
water being purified must be passed, i.e., from the
water intake to the outlet or, in other words, from one
screen to the other.
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A device possessing these characteristics can be
installed permanently on a water faucet in households,
in caterinq establishments, or in industry without
requiring much space.
One preferred embodiment according to the present
inventin is characterized in that the container
comprises on the outside an approximately cylindrical
wall with cover and bottom, at least one of which is
flat. The container can be preferably made of plastic,
with the outside wall being essentially cylindrical.
In the embodiment described here, this outside wall
differs from the exact cylindrical shape inasmuch as
the spiral, seen in the cross section of the container,
delineates a channel flarin~ helically toward the
outside, which channel terminates at a point, so that
here the outside walls must have a transition in the
radial direction. Especially when such a container is
made of plastic, the manufacture is simple in the case
of this embodiment, straight from an injection mold.
Using this mold, a bottom or a cover on which integral
supports for the partitions are molded, after which the
container can be filled with the mass of filter
material and closed after putting on and fastening the
cover. Such a container can also be manufactured at
low cost and with good functional qualities by mass
production. The thickness of the partitions and of the
supports is preferably smaller than that of the
cylindrical wall and/or of the cover and bottom. Yet
due to the plurality of partitions arranged next to
each other, the cover and bottom are at a fixed
distance from each other, and the entire container
represents a compact and stable unit.
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It is also expedient according to the present
invention if the inlet is in the center of the cover in
the form of a guick-release coupling with reducing
nozzle. Thus, the device according to the present
invention can be mounted easily with a flick of the
wrist on a water faucet equipped with a corresponding
coupling, and thereby be ready to use. During the flow
of the water to be purified in continuous operation,
the reducing nozzle provides for a pressure drop from
mains pressure to operating pressure in the container
packed with the packing material, so that damage to or
even an explosion of the container is ruled out with
certainty even when it consists of plastic walls.
Another advantage of the reducing nozzle is the
smoothing of the pressure build-up during the charing
of the water, i.e., during the putting into operation
of the device, when the faucet is opened after the
device is attached and fastened by means of the quick-
release coupling, and the water pressure normally
occurring in the water mains is only present at the
inlet. Reducing the water pressure also results in the
advantage that the flow velocity is reduced, and thus
the contact time of the water with the packing is
prolonged.
In another advantageous embodiment of the present
invention, the reducing nozzle is mounted centrally at
a distance above the top screen in the cover within the
quick-release coupling. The distance between the top
screen and the reducing nozzle crea~es a space inside
the housing of the quick-release coupling which permits
the water to be distributed evenly~ Since, moreover,
the top screen is fixed in the cover inside ~he quick-
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release coupling, i.e., in a mechanically strong, fixedpart, any water pressure that may build up can be held
advantageously without breakage. Such a water
pressure, e.g., the pressure occurring normally in the
water mains, can build up in the housing of the quick-
release coupling due to the entry of dirt with fresh
water and its settling in the quick-release coupling.
Due to the fixed design of the coupling, the increased
pressure building up behind the site of the clogging
can be withstood without any problem, and leakage
occurs. Furthermore, in the case of malfunction with
back pressure, the filter material is held with
certainty in the spiral container rather than being
pressed or flushed into the quick-release coupling due
to the fact that the top screen is mounted in the
cover.
It is also e~pedient according to the present
invention to provide a support element with increased
thickness at least in the central area of the spiral.
If the above-described preferred embodiment of more or
less true spiral shaped is used, mounting the support
element only in the area of the center container can
already be sufficient. Such a support element, e.g.,
in the form of a hydraulically favorable plastic bead,
considerably increased the mechanical strength of the
device according to the present invention. The support
element is preferably attached on the cover or on the
bottom. It then connects these two walls and confers a
very stable shape to the entire container. In other
embodiments with flow paths shapes deviating from the
ideal spiral, such thickened support elements can be
mounted eccentrically and/or in other places. They are
preferably always mounted in the areas with the highest
mechanical stress.
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It is also advantageous accordinq to the present
invention to fasten the outlet at the outer end of the
spiral in the form of a truncated-cone-shaped pipe in
the zone of the lower screen at the bottom. It is thus
possible to qenerate a water jet for the purified water
being discharged, so that the purified water does not
run along the bottom on the outside and drip off in
undesired places in a disadvantageous manner.
While the outlet is preferably at the outer end of
the spiral, the inlet, in the form of the quick-
release coupling, is in the central area instead. The
quick-release coupling as was mentioned above, forms
the means of fastening the device onto a water faucet,
and the entire device is balanced better, i.e. 'r its
weight is distributed more evenly on the water faucet,
if the quick-release coupling with the reducing nozzle
and top screen is in a central position in the device.
As was previously mentioned, the device according
to the present invention can be used in different
areas, e.g., in the household, in catering
establishments, and in industry. While in the latter
case the entire device is discarded as a disposable
unit after the exhaustion of the filter material, the
spiral container (the tank, which is approximately in
the shape of a flat cylinder) can be slid in the manner
of a cassette, such as in the case of recording tape or
videotape, into a decorative unit, which -is attached to
the water faucet. In this decorative unit, the spiral
or cylindrical container represents only an insert,
which is replaced by a new one and discarded when the
packing is exhausted. The state of exhaustion of the
packing is tested by means of a color indicator or,
e.g., by-the taste of the water running from the ~lef-
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In the decorative unit, i.e., in the chromium-plated
filter unit, in which the purification device is
inserted in a removable and replaceable manner, like an
insert or a cassette, there can be, for example, a
two-way valve, which optionally discharges unfiltered
water for simpler uses from the faucet directly into a
basin underneath, or gives filtered water for higher
quality requirements from the device after changing
over. In this case, the shape of the cassette can also
be preferably rectangular, with the pathway arrangement
on the inside being more or less spiral, while in
principle the flow path is spiral-like, i.e., the water
being purified flows from the inside to the outside.
Other advantages, characteristics, and possible
applications are found in the following description in
connection with the drawings. Here:
Fig. 1 shows a cross sectional view taken along
line I-I of Fig. 2 of a water purification device and
of the approximately cylindrical container in the
section in which the flow path is spiral from the
inside to the outside; and
Fig. 2 shows a cross sectional view of the device
according to Fig. 1.
The water purification device comprises the
plastic container designated generally by 1 which has
an approximately cylindrical wall 2, a generally
circular flat top cover 3, and a generally circular
flat bottom 4. Between the cover and the bottom, there
are partitions 5, preferably in a continuous spiral
arrangement. The injection mold for preparing this
container 1 is shaped such that the bottom 4 is
integral with-the cylindrical wall 2 and with the
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spiral dividing partitions 5 are all molded together
with it. In the manufacturing process, the bottom
effluent screen 6 is either shaped simutaneously, or it
is subsequently inserted and welded in. In addition,
there is a thickened support element 8 in the area of
the center of the spiral, which is ,also preferably
molded on the bottom 4. The packing (not shown) is
then charged into the individual spiral canals (ducts)
during the manufacturing, after which the cover 3 is
put in place and is fastened to the cylindrical wall 2
and to the partitions 5, for example, by welding. The
top screen 7 is preferably pre-molded on the cover. A
quick-release coupling 9 is also molded on the cover 3
above the top screen 7.~The water is let in through
this quick-release coupling 9 molded or welded on the
cover 3.
As shown in the figures, the quick-release
coupling 9 is mounted centrally on the cover 3, and is
shown in Fig. 2 with a bead 10, over which a sleeve
grips the faucet in order to create a fixed supporting
connection between thè stationary faucet and the
container 1 after coupling. The quick-release coupling
9 has a reducing nozzle 11 which is mounted in the
quick-release coupling 9 at a distance above the top
screen 7 in such a way that a space 12 is created
between the screen 7 and the nozzle 11. If the water
carried dirt with it, such dirt is able to collect in
this space. Such dirt is prevented from entering to
the packing located in the spiral flow path. It is
clearly recognized that each partition 5 separates two
adjacent paths from each other and forms the inside of
one flow path and at the same time the outside of the
other flow path.
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The outlet at the outer end of the spiral is in
the shape of a truncated conical pipe 13, which is
molded on the bottom 4 and holds the lower screen 6 at
the height of the bottom 4.
In a practical embodiment of such purification
device, a flow rate of 60 liters/hours is reached, even
though a flow rate of 100 liters of water per hours had
already been reached with another embodiment.