Note: Descriptions are shown in the official language in which they were submitted.
CA 02370165 2001-10-23
WO 00/66955 PCT/NL00/00271
Short title: Ice cube apparatus
The invention relates to an ice cube apparatus which is
designed in particular as a desktop and/or stand-alone unit and
is intended in particular for the consumer market.
An apparatus of this nature is known, for example, from
US-A-4,055,053 which, in Figure 8, shows a housing in which
there is a mould chamber. The base of the mould chamber is
largely formed by a plurality of mould trays which, on the
underside, are connected to thermoelectric elements. The mould
chamber is permanently connected to a water system and is kept
permanently completely full of water with the aid of a float
system. Consequently, the mould trays are always automatically
full of water. After the apparatus has been switched to a
freezing position, the thermoelectric elements ensure that the
water in the mould trays freezes. Then, the power supply to the
thermoelectric elements is interrupted, or alternatively these
elements are temporarily switched to a heating state, so that
heat is supplied to the mould trays for a short time. As a
result, the outermost layer of ice melts and the ice cubes are
free to float upwards in the mould chamber. The ice cubes can be
scooped out of the top side of the mould chamber into an ice
bucket with the aid of a chain drive with scoop blades.
A drawback of this known apparatus is that the time
which elapses between when the apparatus is switched on and a
first series of ice cubes is ready is relatively long.
Furthermore, the apparatus comprises a large number of
mechanical components, is relatively expensive to produce and is
unwieldy. The apparatus can only function with a mould chamber
which is completely full, since otherwise the ice cubes which
have floated upwards cannot be scooped out of the apparatus. To
achieve this, the mould chamber has to be permanently connected
to a supply system. The ice cubes which have already been
produced remain floating in the water and slowly melt.
Furthermore, use of the apparatus is unhygienic, since any
contamination remains in the mould chamber and is continuously
mixed with fresh water.
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An apparatus according to the preamble of claim 1 is
known from FR-A-2,747,769, which in Figs. 1 and 2 shows an
apparatus for preparing cold water and ice. water at ambient
temperature can be fed from water bottles which are to be placed
on top of the apparatus to a collection bin located inside the
apparatus. In a variant, the apparatus may also be connected
directly to a water supply system. A controllable valve is
provided between the water bottles or the water supply system
and the collection tray. From the collection tray, water can be
passed via a pump, a system of pipes and a controllable valve to
either an external tap or a distribution pipe located inside the
apparatus. The distribution pipe is provided with a large number
of spray nozzles which are situated just above. a cooling body.
The cooling body is formed by an inclined, elongate plate with
transverse partitions. The spray nozzles atomize water over the
cooling body. At one end, the cooling body is connected to a
peltier element. In the freezing position of the peltier
element, a small amount of the water which reaches the cooling
body can freeze on the said body and can grow in layers to a
limited extent. The water which does not freeze immediately
falls downwards from the cooling body as cooled drops of water
and enters the collection bin. At set times, the current
direction to the peltier element is reversed, with the result
that the bottom layers of ice on the cooling body melt and the
discs of ice lying above it slide off the inclined plate and
fall onto a collection grate which hangs above the collection
tray. On this grate, the discs of ice will begin to melt, the
melt water dropping into the collection tray.
It should be noted that this apparatus is intended in
particular for the preparation of cold water. The formation of
discs of ice is simply a side effect. On the cooling body, it is
only possible to freeze ice with a maximum thickness of a few
millimetres. The first layers of ice which freeze on the cooling
body at the beginning of a freezing cycle provide so much
insulation that further progressive growth of ice is impossible.
Consequently, only thin discs of ice can be formed. The thin
discs of ice will melt away quickly, both on the collection
grate and when they are finally used. For this type of
combination apparatus, this is more of an advantage than a
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disadvantage, since the cold melt water contributes to reducing
the temperature of the water in the collection bin, which can
then be tapped into a glass as cold water via the tap. However,
quickly melting discs of ice are very disadvantageous for an ice
cube apparatus according to the present invention. This is
because in this case cold melt water is an undesirable
by-product. The principal product is the production of ice
cubes.
Therefore, a drawback of the apparatus described in
FR-A-2,747,769 is that only a small amount of the water supplied
can be effectively converted into ice. Moreover, the ice is of
low quality, i.e. it melts very quickly without dissipating much
coldness. A further drawback is that the apparatus can only be
used in combination with the special bottles which are to be
placed on top of the apparatus, or has to be permanently
connected to a water supply system. The bottles limit the
versatility of the apparatus and, moreover, make it unwieldy and
unstable. The water supply system also limits the versatility of
the apparatus and, moreover, means that it has to remain in one
place. A long time is required to make a first quantity of thin
discs of ice. The apparatus has a long start-up time. The water
comes out of the bottles at ambient temperature and passes
directly into the collection bin, in order then to be cooled
slowly by being mixed with water which has been cooled using the
cooling body or with melt water. Discs of ice of some thickness
can only be made after a sufficiently low temperature of the
water in the collection bin has been reached. The mixing is not
only slow but also unhygienic, since mixing often takes place
with water which has already spent a long time in the apparatus.
The thin discs of ice are therefore to a large extent formed
from old water.
The object of the present invention is to provide an
apparatus with which the only principal product made is ice
cubes and in which the above drawbacks are eliminated. In
particular, the invention aims to provide an ice cube apparatus
which is inexpensive, compact and operates quickly and
hygienically and is suitable in particular for the individual
consumer who wants to make a small number of ice cubes from
fresh water within a short time.
13-07-2001 EPO - U(i I NL000027'
CA 02370165 2001-10-23
A00-40031/RR/MMA 13.07.2001 Enclosure to our letter
dated 13 July 2001
Jdl~ 99 PCT/NLOO/00271
Wiltoe Innovatie B.V.
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According to the invention, this object is achieved by means
of an ice cube apparatus according to claim 1. The apparatus
comprises a thermoelectric element and an ice-cube tray which is
connected thereto in a thermally conductive manner. The apparatus is
provided with its own internal water reservoir which, at the start of
a production cycle, can be filled once with a desired amount of
water. From the reservoir, the water can be metered to a mould cavity
of an ice-cube tray with the aid of water-metering means, for example
a pressure pump. The mould cavity is at least one centimetre deep and
consequently is suitable for the production of ice cubes with a
thickness of greater than one centimetre. Control means with a timer
unit then ensure that the thermoelectric element is supplied with
current for a defined, set freezing time, in such a manner that heat
is extracted from the ice-cube tray. On the other side of the
thermoelectric element, this heat is released again to the
environment. After the freezing time has elapsed, release means which
release the ice cube from the tray come into operation. The ice cube
is collected and removed by removal means which are arranged beneath
or next to the tray. The apparatus may comprise its own battery power
supply or may be equipped with a plug for connection to an
electricity grid. Consequently, the invention provides an ice cube
apparatus which operates completely independently. The apparatus
simply has to be switched on after the water reservoir has been
filled with a defined amount of water. Since the apparatus is
provided with a scale, the amount of water can be adapted to the
desired number of ice cubes. Then, the apparatus will produce a
plurality of ice cubes in succession, in a continuous process, which
are collected and removed via the removal means. The apparatus is
structurally simple, inexpensive to produce and hygienic to use. The
various components interact virtually without any noise and make it
possible to construct an apparatus of very small dimensions, for
example with a housing which holds the various components and
measures 15 x 15 x 25 cm. Consequently, the apparatus is eminently
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suitable for use at home and in hotel rooms and the like. The use of
mechanical components, such as controllable valves, is limited, which
increases the reliability of the apparatus and means that maintenance
is limited to a minimum. Surprisingly it has been
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found that the time which is required to produce a series of ice
cubes of standard size, for example approximately 8 cm3, using
the apparatus according to the invention is less than
minutes, and in particular only a few minutes.
5 Preferred embodiments of the invention are defined in
the subclaims.
The invention will be explained in more detail with
reference to the appended drawing, in which:
Fig. 1 shows a diagrammatic, perspective view of a first
10 embodiment of the ice cube apparatus according to the invention,
with the surrounding housing having been omitted;
Fig. 2 shows a view corresponding to Fig. 1 of a
preferred embodiment of an ice cube apparatus in a freezing
position;
Fig. 3 shows a partial view of Fig. 2, in a release
position;
Fig. 4 shows a perspective view, with exploded
components, of an ice-cube tray with cylinder part and an insert
element with piston part; and
Fig. 5 shows a cross-sectional view through the
assembled components from Fig. 4, in a release position.
In Fig. 1, for the sake of clarity the ice cube
apparatus is illustrated without its surrounding housing. The
surrounding housing can be shaped as desired with an appearance
which, for example, fits in with other consumer electronics
and/or kitchen equipment. The apparatus comprises a water
reservoir 1 with a filling opening 3. The filling opening 3 may
preferably be closed off by a cover. The water reservoir 1 is
connected to water-metering means, which in this case are formed
by a pump unit. On the pump side, the pump unit is connected to
a filler tube 5 which extends upwards from the bottom of the
reservoir 1 and opens out into a metering unit '6 with four
nozzles 7. In the top of the apparatus, there is an ice-cube
tray 10 in which there are four mould cavities 11 which can be
filled with water via the nozzles 7 at the start of a freezing
cycle.
On two opposite sides, the ice-cube tray 10 is delimited
by thermoelectric elements 15, which in this case are formed by
peltier elements. If the peltier elements are connected to a DC
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voltage source, depending on the current direction, heat will be
extracted on one side of the peltier element and an amount of
heat will be emitted on the other side. Consequently, the
peltier element can act as a heat pump, by means of which it is
possible to extract sufficient heat from the ice-cube tray 10
for the water in the mould cavities 11 to freeze and form ice
cubes.
The various components of the apparatus are attached to
a wall plate 19, from which an electricity cable 20 also
extends, which can be plugged into a wall socket in order to
supply in particular the pump unit and the peltier elements with
current. In the apparatus, there are control means 21 which
comprise a timer unit for activating the various components of
the apparatus in a defined order and for defined times.
The two thermoelectric elements 15, together with the
ice-cube tray 10 suspended between them, are arranged in such a
way that they can rotate about a pivot pin 22. The pivot pin 22
is connected to a drive 23 which is formed, for example, by an
electric motor. The drive 23 is activated by the control means
21 and can ensure that the ice-cube tray 10 is turned over at
set times, so that the ice cubes which have formed in the mould
cavities 11 fall out.
A funnel-like collection container 25 is arranged
beneath the ice-cube tray 10. The collection container 25 is
preferably large enough to accommodate a number of ice cubes
which corresponds to a full water reservoir 1. On its underside,
the collection container 25 is provided with a slide-out drawer
26 for the removal of ice cubes. In its base part, the drawer 26
is provided with one or more leakage openings allowing melt
water to flow out. The leakage opening opens out above a leak
bin 28. Any melt water, and also water which is spilt during
filling of the ice-cube tray 10 automatically passes into the
leak bin 28, which can be removed from the apparatus and emptied
or is provided, on its underside, with a closable outlet
opening. The columnar arrangement of the leak bin 28, the
collection container 25 and the ice-cube tray 10 has the further
advantage that, in the event of a power failure, all the melt
water which is released from ice cubes which have already been
produced is collected in the leak bin 28. The leak bin 28
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advantageously ensures that ice cubes are only produced from
fresh water. This is of benefit to the taste and, in addition,
is hygienic.
During use, the water reservoir 1 is filled with, for
example, half a litre of tap water. Then, the apparatus can be
switched on by pressing a switch 30. The control means 21 will
then begin by switching on the pump unit for a defined filling
time, the filling time being precisely sufficient to fill the
mould cavities 11 with water. The pump unit is switched off and
the thermoelectric elements 15 are switched to a freezing
position for a defined freezing time, in which they are supplied
with current in such a manner that heat is extracted on the side
of the ice-cube tray 10. The ice-cube tray 10 is simultaneously
cooled from two sides to below the freezing point in an
efficient and very rapid way, with the result that the water in
the mould cavities 11 freezes. During freezing, the heat which
is released on those faces of the thermoelectric elements 15
which lie opposite the ice-cube tray 10 has to be dissipated.
For this purpose, these surfaces may be provided with cooling
ribs. Furthermore, there is a fan 32 which, during freezing,
releases a flow of air along the cooling ribs. The flow of air
is discharged to the atmosphere via a grate in the surrounding
housing. After the freezing time has elapsed, the current to the
thermoelectric elements 15 is switched off for a defined release
time. The heat which is then still stored in the cooling ribs
flows back to the ice-cube tray 10, with the result that the
outer layers of ice of the ice cubes melt and the ice cubes then
rest freely inside the mould cavities 11. In a variant, the
current direction to the thermoelectric elements 15 is reversed,
as a result of which these elements begin to emit heat on the
side of the ice-cube tray 10. Then, the release means are
activated, which in this embodiment means that the drive 23
turns over the ice-cube tray 10 and empties it into the
collection container 25. A fresh freezing cycle can then begin.
The ice-cube tray 10 is returned to its original position, the
mould cavities 11 are filled again with water, etc. The freezing
cycle for freezing four ice cubes will continue to repeat itself
automatically until either the water reservoir 1 is empty or the
collection container 25 has been completely filled with ice
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cubes. The water reservoir 1 or the collection container 25 may
to this end be fitted with suitable level detectors which emit a
signal to the control means 21.
The water reservoir 1 is provided with a scale 35 which
indicates the amount of water and the quantity of ice cubes
which can be produced with this amount. The scale may also
include an indication of the production time required. The
amount of ice cubes to be produced can be determined by the user
himself by filling the water reservoir 1 to a greater or lesser
extent. The water reservoir 1 preferably has a volume of 0.1-
1.5 litres, in particular 0.5-1.0 litre. This corresponds to the
average requirement for ice cubes while ensuring that the
apparatus remains compact and manageable.
Operating on the basis of ice cubes with a volume of
approximately 8 cm3, the apparatus has proven able to produce
approximately 60 ice cubes within a period of approximately one
hour. The freezing time required for the production of a series
of four ice cubes, each with a volume of approximately 8 cm3, is
less than ten minutes and in particular only a few minutes.
The ice cubes produced are held at a temperature of
approximately 0 C in the collection container 25. The collection
container 25 can be insulated or supplied with cold derived from
the thermoelectric elements 15. As a result, the ice cubes
produced can be stored for a certain time.
The ice-cube tray 10 is preferably made from aluminium,
which is a good thermal conductor. To further minimize the
production time and the amount of energy required, the ice-cube
tray 10 is designed to be as thin-walled as possible. In a
particular embodiment, the mould cavities 11 of the ice-cube
tray 10 are lined with a layer of teflon, so that the ice cubes
can be released from the mould cavities 11 more easily.
In a variant embodiment which is not shown, the ice cube
apparatus comprises an ice-cube tray with a bottom which can be
slid or tilted away and, with the aid of a suitable drive during
a release operation, can be moved into an open position. The ice
cubes can then fall freely downwards into a collection container
arranged below.
Fig. 2 shows a variant embodiment of the ice cube
apparatus. In this figure too, the surrounding housing has been
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omitted for the sake of clarity. The apparatus comprises a water
reservoir 40 with a filling funnel 41 and a pump unit 42, which
is connected to the reservoir and, via a filling tube 43, is
connected to an ice-cube tray 45 with two mould cavities 46. The
ice-cube tray 45 is delimited on two sides by two peltier
elements 47 with cooling ribs 48. Beneath the ice-cube tray 45
there is a collection container 49, which in this case is formed
by an inclined chute which opens out into a closable dispensing
opening.
The ice-cube tray 45 comprises an insert element 50
which can be moved up and down between a bottom position
(Fig. 2) and a top position (Fig. 3) . The insert element 50
comprises a lifting part which, in the bottom, position, bears
against the base of the mould cavity 44. If, during a release
operation after freezing, the insert element 50 is moved upwards
into the top position, the lifting part pushes the ice cube
upwards with it until ultimately it is tipped over the edge of
the ice-cube tray 45 and falls into the collection container 49.
The insert element 50 can be moved up and down using any
suitable drive. Advantageously, however, water pressure from the
pump unit 48 is used. In this case, it is even possible to fill
the mould cavities 46 with water while the insert element 50 is
moving upwards. In this way, the release of the ice cubes is
combined with the operation of filling the mould cavities, which
saves time and eliminates the need for a separate drive for the
release means. The above release principle will be explained in
more detail with reference to a variant of an ice-cube tray with
insert element which is shown in Figures 4 and S.
In Figs. 4 and 5, the ice-cube tray 60 is of cuboidal
design and has a circular recess arranged in its base. A filler
piece with a cylinder part 61 is arranged in the ice-cube tray
60 from below. An insert element 62 is arranged above the top
section of the cylinder part 61, in such a way that it can slide
up and down. The insert element 62 comprises a piston part 63
which rests inside the cylinder part 61. The piston-cylinder
system which is formed in this way can be connected, by means of
a connection port 64, to, for example, the filler tube 43 of the
pump unit 42 of the ice cube apparatus shown in Fig. 2. When the
pump unit is set in operation, the water pressure built up
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ensures that the piston part 63, together with the rest of the
insert element 62, is pushed upwards with respect to the
cylinder part 61 and the ice-cube tray 60. The upwards travel
can be limited by a stop pin 68 mounted in the piston part 63 or
by the top side of the insert element 62 coming into contact
with a spring means or stop wall.
As can be seen in Fig. 5, the cylinder part 61 is
provided on its top side with two inlet openings 65 which, in
the top position of the insert element 62, are opened by a
narrowing 69 in the piston part 63. From that moment, the water
can flow into the mould cavities. When the mould cavities have
been filled, the pump unit can be switched off, with the result
that the water pressure drops and the insert element 62 can move
back into its bottom position, for example under the influence
of a spring means or the force of gravity.
The insert element 62 has a vertical wall part 70 which
forms a partition between the mould cavities in the ice-cube
tray 60. In addition, the insert element 62 comprises two
lifting parts 71 which extend on either side of the vertical
wall part 70. The two lifting parts 71 are inclined, ensuring
that, in the top position of the insert element 62, the two ice
cubes are pushed outwards over the sides of the ice-cube tray
60. This is advantageous in particular if the assembly of ice-
cube tray 60 and insert element 62 is clamped between two
thermoelectric elements, since the release direction can then be
directed between the two thermoelectric elements.
It is advantageously possible to make the lifting parts
71 and the vertical wall 70 of any desired shape. In this way,
the final shape of the ice cubes is defined, so that they can be
given an attractive appearance. Since, in addition, the insert
element 70 is easy to exchange, the ice cube apparatus can
easily and quickly be adapted to a desired shape of ice cube,
for example with the logo of a hotel chain.
The release principle illustrated in Fig. 2 may
advantageously also be employed in Fig. 1, and vice versa, so
that in this case too the fresh water is kept separate from
water which has already been used or used water is returned to
the water reservoir for reuse.
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Consequently, the invention provides an ice cube
apparatus which operates simply, quickly and effectively and is
of acceptably small size, making the apparatus very suitable for
use as a stand-alone unit in, for example, a home or a hotel
room. In addition to the embodiments shown, numerous variants
are conceivable. For example, the water reservoir may be
arranged removably in the housing, so that it can be taken out
of the apparatus and filled beneath a tap. It is also possible
for the collection container to be fitted removably. To collect
melt water, a separate leak bin may be provided beneath the
removal means. Keeping the melt water outside the water
reservoir in this way advantageously ensures that only fresh
water is used to make the ice cubes.
