Water dispenser abstract
A germfree drinking water dispenser includes a reservoir for receiving
and reserving drinking water such as mineral water and an ozone
injecting device. The ozone injecting device includes a compact
ozone generator and an injection opening which is opened into the
reservoir. Ozone generated by the ozone generator is injected, by
e.g. a blower, through the injection opening into the drinking water
at the reservoir. The ozone injecting device is activated only for
a short necessary period of time when the dispenser is out of service.
So that, after the drinking water in the reservoir is fully sterilized,
a sufficient period of time is allowed to lapse for any ozone remaining
in the water to dissolve until the next first use of the dispenser.
Water dispenser claims
What is claimed is:
1. A drinking water dispenser for dispensing drinking water, such
as mineral water, under a germfree condition, comprising:
a reservoir for receiving and reserving said drinking water;
a bottle filled with said drinking water, said bottle having only
one opening, said opening being a bottle-neck opening;
an inlet opening formed at an upper portion of said reservoir for
allowing introduction of said bottle-neck opening and thereby rendering
said reservoir airtight; and
an ozone injecting means including an ozone generator and an injection
opening for injecting ozone generated by the ozone generator into
said drinking water reserved at said reservoir through a feed pipe;
wherein said injection opening is provided with an anti-reverse
means for preventing reverse flow of said water from said reservoir
to said feed pipe.
2. A drinking water dispenser according to claim 1 further comprising:
a control means for automatically starting said ozone injecting
means and stopping said ozone injecting means after lapse of a predetermined
time period when said dispenser is out of service.
3. A drinking water dispenser according to claim 2 wherein said
control means controls said ozone injecting means such that the
concentration of ozone remaining in said drinking water may not
exceed 0.5 ppm and said ozone injecting means may be stopped for
more than 4 hours before said dispenser is used.
4. A drinking water dispenser according to claim 1 wherein flow-down
pipe for dispensing said water is connected to a bottom of said
reservoir, and a heating means for heating said water is provided
adjacent a base end of said flow-down pipe, said injecting opening
of said ozone injecting means being disposed in said bottom of said
5. A drinking water dispenser according to claim 1 wherein said
anti-reverse means comprises a hydrophobic gas-permeable membrane.
Water dispenser description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a drinking water dispenser for
domestic and/or commercial use for dispensing drinking water such
as mineral water with the water being sterilized.
2. Description of the Related Art
Conventionally, no drinking water dispensers of the above-noted
type have been equipped with means for sterilizing water reserved
therein. Such dispenser generally includes a bottle filled with
the drinking water such as mineral water and a reservoir for receiving
and reserving the drinking water flowed down from the bottle. The
filling operation of e.g. the mineral water into the bottle is done
in a sanitary manner at a factory under a strict quality control.
Thus, even if the mineral water or natural water contains no germicide
such as free chlorine therein, the water may be maintained at the
germfree condition as long as the water is kept within the sealed
However, after the water is removed from the bottle into the reservoir,
rapid germ propagation occurs due to the contact of the water with
the ambience air. For this reason, after being kept for an extended
period of time, there develops muddiness in the water, and this
muddiness deteriorates the taste of the drinking water.
In order to restrict such germ propagation detrimental to the drinking
water, the prior art has suggested periodical cleaning of the reservoir
with hot water or water-draining and drying of the reservoir. However,
these operations are not only troublesome, but uneconomical because
not inexpensive bottled water has to be disposed of wastefully.
In view of the above-described state of the art, a primary object
of the present invention is to provide an economical drinking-water
dispenser having sterilizing means, which can eliminate e.g. the
troublesome reservoir cleaning operation as well as the necessity
of wasteful disposal of the bottled water.
Summary of the Invention
For accomplishing the above-described object, a germfree drinking
water dispenser, according to the invention, comprises a reservoir
for receiving and reserving drinking water and an ozone injecting
means. The ozone injecting means includes a compact ozone generator
and an inlet opening which is opened into the reservoir. Ozone generated
by the ozone generator is injected, by means of e.g. a blower, through
the inlet opening into the water reserved within the reservoir.
The drinking water reserved at the reservoir can be sufficiently
sterilized by the injected ozone. Further, the injected ozone can
be dissolved to be non-hazardous with lapse of time. Accordingly,
the ozone injecting means should be operated only for a short period
of time during night hours when the dispenser is not used, so that
an appropriate amount of time may be secured for allowing the remaining
ozone to be sufficiently dissolved before the dispenser is used.
Extensive experiments show that with adequate adjustment of the
injection amount the remaining ozone may be sufficiently dissolved
to ensure safety of the drinking water and the reserved water need
not be disposed of. For instance, germ propagation can be restricted
to a satisfactory degree by operating the ozone injecting means
for 10 to 60 minutes in a day. And, the experiments show that remaining
ozone, if at the level of no more than 0.5 ppm, can be completely
dissolved within four hours.
The above-described drinking water dispenser of the invention preferably
includes a control means for automatically starting the ozone injecting
means and stopping this injecting means after lapse of a predetermined
time period. With this, it becomes possible to automatically and
reliably effect the above-described process of starting the ozone
injecting means, stopping the injecting means, and then allowing
the time period necessary for the dissolution of the remaining ozone
to lapse before the use of the dispenser.
The drinking-water generally includes a heater unit and/or cooler
unit for producing heated and/or cooled water. In the vicinity of
the cooler unit, there prevails such a temperature as to restrict
propagation of germs. On the other hand, in the vicinity of the
heater unit, the prevailing temperature will range between 20 and
35 degrees in Celsius which temperature range is suitable for promoting
germ propagation. For this reason, when e.g. the mineral water (containing
no germicide such as free chlorine) reserved at the reservoir is
left un-used approximately for one week, there tends to develop
visible whity muddiness, or even bubbling of metabolism in the water
due to the propagation of germ therein.
Therefore, the inlet opening should preferably be disposed at such
portion of the ozone injecting means as tending to promote the germ
propagation. In particular, when a flow-down pipe for dispensing
water is attached to the bottom of the reservoir and the heater
means for heating the water is disposed at the base end of the flow-down
pipe, the inlet opening of the ozone injecting means should be formed
at this bottom of the reservoir.
Further and other objects, features and effects of the invention
will become more apparent from the following more detailed description
of the embodiments of the invention with reference to the accompanying
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 schematically shows a construction of a germfree drinking
water dispenser according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIG. 1 a germfree drinking water dispenser includes
a body 1 and a bottle 2 filled with such drinking water as mineral
water. The body 1 has a case 3 in which a reservoir 4 is housed.
An inlet opening 4A is formed at an upper position of the reservoir
4 and an opening 5 is formed in a top plate of the case 3. The
bottle 2 is turned upside down with its bottle-neck opening 2a oriented
downward and is supported, in this posture, to the top plate of
the case 3 of the body 1 so that the bottle-neck opening 2a is
inserted through the inlet opening 4a into the reservoir 4.
The drinking water in the bottle 2 flows down through the opening
2a and is temporarily reserved inside the reservoir 4. Then, the
water surface in the bottle will be in a level where equilibrium
is established between a pressure inside the bottle 2 acting on
this water surface and an atmospheric pressure acting on the water
surface inside the reservoir 4.
The drinking water reserved in the reservoir 4 can be dispensed
from a dispensing tap 7a through a flow-down pipe 6a communicating
with the bottom of the reservoir 4. Further, cooled water can be
dispensed from a further dispensing tap 7b through a further flow-down
pipe 6b. And, heated water can be dispensed through a still further
dispensing tap 7c through a still further flow-down pipe 6c. At
a base end of the flow-down pipe 6b for the cooled water, there
is provided an evaporator 8a, as a cooler means, of a heat pump.
Similarly, at a base end of the flow-down pipe 6c for the heated
water, there is provided a sheathed heater 8b, as a heater means,
of the heat pump. In the drawing, reference numerals 9 10 and 11
denote a compressor, a condenser and a fan of the heat pump, respectively.
The dispenser further includes an ozone injecting means for injecting
air containing sterilizing ozone into the drinking water reserved
within the reservoir 4. This ozone injecting means includes a compact
ozone generator 12 a blower 13 a feed pipe 14 for feeding the
ozone-containing air and an injection opening 15 formed at the leading
end of the feed pipe 14.
The ozone generator 12 which per se is conventional, includes
a ceramic panel 12a and a high-voltage power source 12b. The ceramic
panel 12a is accommodated within a small chamber formed at an intermediate
position of a feed pipe for air fed by the blower 13. As this ceramic
panel 12a is impressed with a high potential from the power source
12 ozone is generated. The generation amount of ozone is adjustable
by a variable resistor attached to the high-voltage power source
12. A portion of the air fed by the blower 13 is made into ozone
by means of the ozone generator 12; and this ozone-containing air
is guided through the feed pipe 14 and the injection opening 15
and directly injected into the drinking water inside the reservoir.
More particularly, the ozone-containing air in the form of air bubbles
is dissolved into the drinking water through the inlet opening 15
opened at the bottom of the reservoir 4. Incidentally, the inlet
opening 15 is provided with either an air diffusing means such a
hydrophobic gas-permeable membrane or an anti-reverse means such
as an anti-reverse valve, thereby to prevent flow of the water from
the reservoir 4 to the feed pipe 14.
Further, a control means 16 is provided for controlling activation
and de-activation of the ozone injecting means. This control means
16 has a real-time clock function and a timer function, so that
the control means 6 automatically activates the ozone injecting
means at a time (e.g. night time) when the drinking water is not
dispensed from the dispenser and then de-activates the injecting
means after a predetermined time period. For instance, the control
means 6 can activate the ozone generator 12 for 30 (thirty) minutes
starting at 1 A.M. Further, prior to the activation of the injecting
means, the control means 6 also checks to make sure that the level
of the drinking water in the reservoir 4 exceeds a predetermined
level, so as not to activate the injecting means when the level
does not exceed the predetermined level.
As described above, according to the dispenser of the invention,
the drinking water in the reservoir 4 is sterilized during its out-of-service
hours (e.g. night hours) to allow lapse of sufficient period of
time necessary for the ozone content to be dissolved before a user
starts using the dispenser in the morning, for example.
Next will be described the extensive experiments conducted by this
inventor to confirm the effect of the drinking water dispenser having
the above-described ozone injecting means.
In the present experiments, the reservoir 4 had the dimensions
of 30 cm.times.30 cm.times.35 cm (effective water depth: 20 cm)
and the storage capacity of 18 liters. The blower 13 had the air
feed capacity of 0.5 to 1 liter/min. The ozone generator 12 was
adjusted to generate ozone at 4.5 to 5.0 mg/hr. And, the ozone injection
was done one time in a day. The injection time periods were varied
in three ways of 20 30 and 60 minutes. During the experiment period,
the drinking water was sampled from the heated-water tap 7c, by
2 (two) liters x two times a day (4 liters in total). The measurement
of the number of germs present in the reservoir 4 was done by using
a standard agar cultivation medium, and the numbers of living germs
were counted for those which formed a colony in the medium after
cultivation for 48 hours at 36 degrees in Celsius.
As illustrated in the above Table, the injection amounts of ozone
varied at 0.17 ppm, 0.25 ppm and 0.5 ppm, respectively for the injection
time periods of 20 30 and 60 minutes. As shown, even with the lowest
ozone concentration of 0.17 ppm, the number of living germs was
lower than 10.sup.2 ; and with the 0.25 ppm concentration, no germs
were observed at all in any cases and the water was observed as
clear, tasteless and odorless as the new mineral water.
The present invention is not limited to the above-described embodiments
but may be modified in many ways without departing from the subject.
For instance, the high-voltage power source 12b of the ozone generator
and the control means 16 may be constructed as one integral unit.
The ozone injecting means may be activated and de-activated manually.
Further, in the disclosed embodiment, the blower feeds the air to
the injecting means for a portion of this air to be made into ozone,
and the injecting means injects this ozone-containing air into the
drinking water. Instead, the injecting means may be designed to
periodically ozonize a small portion of liquid oxygen stored at
an oxygen tank to inject it into the drinking water.
The invention may be embodied in other specific forms without departing
from the spirit or essential characteristics thereof. The present
embodiments are therefore to be considered in all respects as illustrative
and not restrictive, the scope of the invention being indicated
by the appended claims rather than by the foregoing description
and all changes which become within the meaning and range of equivalency
of the claims are therefore intended to be embraced therein.