U.S. patent application number 17/535416 was filed with the patent office on 2022-03-17 for system for heating and frothing a beverage, a device for heating and frothing a beverage suitable for being used in such a system, a froth wand suitable for being used in such a system and a method of preparing a beverage using such a system.
The applicant listed for this patent is Koninklijke Douwe Egberts B.V.. Invention is credited to Hendrik Johan Dees, Hendrikus Christinus Maria Wessels.
Application Number | 20220079374 17/535416 |
Document ID | / |
Family ID | 1000005990329 |
Filed Date | 2022-03-17 |
United States Patent
Application |
20220079374 |
Kind Code |
A1 |
Wessels; Hendrikus Christinus Maria
; et al. |
March 17, 2022 |
SYSTEM FOR HEATING AND FROTHING A BEVERAGE, A DEVICE FOR HEATING
AND FROTHING A BEVERAGE SUITABLE FOR BEING USED IN SUCH A SYSTEM, A
FROTH WAND SUITABLE FOR BEING USED IN SUCH A SYSTEM AND A METHOD OF
PREPARING A BEVERAGE USING SUCH A SYSTEM
Abstract
A system for heating and frothing a beverage comprises a device
for heating and frothing a beverage and a froth wand. The device
for heating and frothing a beverage includes a steamer, a steam
conduit connecting the steamer to a steam nozzle and a froth wand
holder for removably holding a froth wand. The froth wand is a
disposable froth wand and comprises a tubular wall having a steam
inlet end comprising a steam inlet, a steam outlet end comprising a
steam outlet separate from the steam inlet and a steam channel
extending between the steam inlet and the steam outlet. The froth
wand holder is arranged for holding the disposable froth wand at
least in an operational position in the device for heating and
frothing a beverage in which operational position the steam nozzle
is in communication with the steam inlet of the disposable froth
wand.
Inventors: |
Wessels; Hendrikus Christinus
Maria; (Utrecht, NL) ; Dees; Hendrik Johan;
(Utrecht, NL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Koninklijke Douwe Egberts B.V. |
Utrecht |
|
NL |
|
|
Family ID: |
1000005990329 |
Appl. No.: |
17/535416 |
Filed: |
November 24, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15855349 |
Dec 27, 2017 |
11213161 |
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17535416 |
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PCT/NL2016/050465 |
Jun 30, 2016 |
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15855349 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A47J 31/4489 20130101;
A23F 5/26 20130101; A47J 31/58 20130101; A47J 31/4425 20130101 |
International
Class: |
A47J 31/44 20060101
A47J031/44; A47J 31/58 20060101 A47J031/58 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 1, 2015 |
NL |
2015068 |
Claims
1. A system for heating and frothing a beverage, said system
comprising a device for heating and frothing a beverage and a froth
wand, said device for heating and frothing a beverage including a
steamer, a steam conduit connecting the steamer to a steam nozzle,
a controller operationally connected to the steamer for controlling
operation of the steamer, a froth temperature sensor for sensing a
temperature of froth in the cup, said temperature sensor being
operationally connected to said controller for supplying thereto a
signal indicative for the measured froth temperature, and a froth
wand holder for removably holding a froth wand, said froth wand
being a disposable froth wand comprising a tubular wall having a
steam inlet end comprising a steam inlet, a steam outlet end
comprising a steam outlet separate from the steam inlet and a steam
channel extending between the steam inlet and the steam outlet,
said froth wand holder being arranged for holding the disposable
froth wand at least in an operational position in the device for
heating and frothing a beverage in which operational position the
steam nozzle is in communication with the steam inlet of the
disposable froth wand, and wherein the froth temperature sensor
comprises a plurality of microphones, each positioned above the
cup, beside the cup above the upper edge of the cup or beside the
cup below the upper edge of the cup.
2. A system for heating and frothing a beverage according to claim
1, wherein the plurality of microphones comprise at least one
microphone positioned above the cup, and at least one microphone
positioned beside the cup above or below the upper edge of the
cup.
3. A system for heating and frothing a beverage according to claim
1, wherein the plurality of microphones comprise at least one
microphone positioned beside the cup above the upper edge of the
cup, and at least one microphone positioned beside the cup below
the upper edge of the cup.
4. A system for heating and frothing a beverage according to claim
1, wherein the steam conduit comprises an air inlet, and the device
for heating and frothing a beverage comprises an air pump connected
to the air inlet via an active air inlet tube, wherein the
controller is operationally connected to the air pump for
controlling the operation of the air pump.
5. A system for heating and frothing a beverage according to claim
4, wherein the steam conduit comprises a passive air inlet and the
air pump is connected to an active air inlet, wherein the device
for heating and frothing a beverage comprises a valve displaceable
in a respective connection position for either connecting the steam
conduit to the passive air inlet or the active air inlet, and
wherein the controller is operationally connected to the valve for
positioning the valve in a respective connecting position.
6. A system for heating and frothing a beverage according to claim
1, wherein the device for heating and frothing a beverage comprises
a reservoir for cold water, a cold water conduit and a cold water
pump for supplying cold water to the steamer, and wherein the
controller is operationally connected to the cold water pump for
controlling the operation of the cold water pump.
7. A device for heating and frothing a beverage suitable for being
used in a system for heating and frothing a beverage according to
claim 1, wherein said device for heating and frothing a beverage
includes a steamer, a steam conduit connecting the steamer to a
steam nozzle, a controller operationally connected to the steamer
for controlling the operation of the steamer, a froth temperature
sensor for sensing a temperature of froth in a cup, said
temperature sensor being operationally connected to said controller
for supplying thereto a signal indicative for the measured froth
temperature, and a froth wand holder for removably holding a
disposable froth wand, said froth wand holder being arranged for
holding the disposable froth wand at least in an operational
position in the device for heating and frothing a beverage, wherein
the froth temperature sensor comprises a plurality of microphones,
each positioned above the cup, beside the cup above the upper edge
of the cup or beside the cup below the upper edge of the cup.
8. A device as claimed in claim 7, wherein the plurality of
microphones comprise at least one microphone positioned above the
cup, and at least one microphone positioned beside the cup above or
below the upper edge of the cup.
9. A device as claimed in claim 7, wherein the plurality of
microphones comprise at least one microphone positioned beside the
cup above the upper edge of the cup, and at least one microphone
positioned beside the cup below the upper edge of the cup.
10. A device for heating and frothing a beverage according to claim
7, comprising an air pump connected to an air inlet of the steam
conduit via an active air inlet tube, wherein the active air inlet
tube comprises an air orifice, and wherein the controller is
operationally connected to the air pump for controlling the
operation of the air pump.
11. A device for heating and frothing a beverage according to claim
7, comprising a reservoir for cold water, a cold water conduit and
a cold water pump for supplying cold water to the steamer, and
wherein the controller is operationally connected to the cold water
pump for controlling the operation of the cold water pump.
12. A method of preparing a beverage using a system for heating and
frothing a beverage according to claim 1, wherein the method
comprises the step of positioning a froth wand in the froth wand
holder of the device for heating and frothing a beverage such that
the froth wand is held in the froth wand holder in a substantially
vertical position, the step of activating the device for heating
and frothing a beverage when the froth wand holder is in the
operational position in the device for heating and frothing a
beverage in which operational position the steam nozzle is in
communication with the steam inlet of the froth wand, the step of
supplying steam to and through the froth wand, the step of
releasing the froth wand from the froth wand holder after steam has
passed a predetermined number of times through the froth wand and
the step of disposing the froth wand, and the step of measuring the
temperature of the froth in the cup, wherein the step of measuring
the temperature of the froth comprises the step of recording sound
from the froth and the step of deriving the temperature from the
recorded sound.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation U.S. application Ser. No.
15/855,349, filed Dec. 27, 2017, which is a continuation of
PCT/NL2016/050465, filed Jun. 30, 2016, which claims the benefit of
and priority to Netherlands Application No. NL 2015068, filed Jul.
1, 2015, the entire contents of each of which are incorporated
herein by reference.
BACKGROUND
[0002] The invention relates to a system for heating and frothing a
beverage, said system comprising a device for heating and frothing
a beverage and a froth wand, said device for heating and frothing a
beverage including a steamer, a steam conduit connecting the
steamer to a steam nozzle and a froth wand holder for removably
holding a froth wand.
[0003] Such a system for heating and frothing a beverage is e.g.
known from US-A1-2003/0131735. This known system comprises an
elongate frothing wand that includes a generally tubular external
sleeve and an inner core within the external sleeve. The inner core
defines a steam conduit configured to pass steam from a supply end
of the froth wand to an expulsion end of the froth wand configured
to eject steam into the beverage. The inner core further includes a
coupling mechanism, configured to facilitate connection of the
froth wand to a steam supply of beverage preparation device. The
coupling mechanism may include threads, clamps, grooves, quick
connect mechanisms, or other suitable fasteners complementarily
configured to connect with steam supply and allow for easy
de-coupling and re-coupling of the frothing wand from the steam
supply to facilitate maintenance and cleaning. In addition the
external sleeve may be easily removed facilitating cleaning and
repair. For example, the external sleeve may be easily removed
after a beverage of one flavor is prepared, so as to minimize the
risk of imparting an undesired flavor to a subsequently prepared
beverage. In addition, several different external sleeves
individually configured to accommodate specific functions may be
interchangeably coupled to the frothing wand, thus diversifying the
utility of the frothing wand. Although the known system allows for
removing the froth wand in order to clean the froth wand,
de-coupling and re-coupling of the froth wand including cleaning
the froth wand requires a lot of time. In particular it is
desirable from a hygienic point of view that the froth wand is
de-coupled, cleaned and re-coupled each time is has been used and
this makes the use of such a system somewhat impractical, with the
result that users of the system frequently refrain from cleaning
the froth wand after it has been used, which could lead to health
risks. In addition, a contaminated froth wand may also contaminate
the inside of the beverage preparation device, which inside device
contamination may be hard to remove.
SUMMARY
[0004] It is therefore an object of the invention to provide a
system for heating and frothing a beverage with which a beverage
can be heated and frothed hygienically. It is furthermore an object
of the invention to provide a system for heating and frothing a
beverage in which contamination of the device for heating and
frothing a beverage as a result of a contaminated froth wand can at
least largely be prevented. It is furthermore an object of the
invention to provide a system for heating and frothing a beverage
which is very user friendly thereby providing a more appealing
manner of preparing a beverage.
[0005] In order to achieve at least one of the above identified
objects the invention provides a system for heating and frothing a
beverage, said system comprising a device for heating and frothing
a beverage and a froth wand, said device for heating and frothing a
beverage including a steamer, a steam conduit connecting the
steamer to a steam nozzle and a froth wand holder for removably
holding a froth wand, said froth wand being a disposable froth wand
comprising a tubular wall having a steam inlet end comprising a
steam inlet, a steam outlet end comprising a steam outlet separate
from the steam inlet and a steam channel extending between the
steam inlet and the steam outlet, said froth wand holder being
arranged for holding the disposable froth wand at least in an
operational position in the device for heating and frothing a
beverage in which operational position the steam nozzle is in
communication with the steam inlet of the disposable froth wand. By
using a disposable froth wand in stead of a reusable froth wand the
system for heating and frothing a beverage can be used in a very
hygienic manner, while at the same time two separate beverages can
be prepared in a shorter time period since cleaning of a used froth
wand can be dispensed with.
[0006] In an environmental advantageous embodiment of a system for
heating and frothing a beverage according to the invention the
disposable froth wand is made of biodegradable material.
[0007] Amongst other things dependent on the preference of a user
and the kind of beverage to be heated or frothed the steam outlet
can extend radially through the tubular wall or can be arranged at
a free end of the froth wand extending in longitudinal direction.
It has appeared that the orientation of the steam outlet influences
the frothing and this orientation can thus be used to adapt the
frothing to at least some extent to the preference of a user. In
addition, frothing seems to be influenced by the number of steam
openings forming the steam outlet, and consequently in a further
embodiment of a system for heating and frothing a beverage the
steam outlet comprises one or more outlet openings.
[0008] In a further embodiment of a system for heating and frothing
a beverage according to the invention heating a frothing a beverage
can be realized in a reproducible and effective manner when the
steam outlet is a circular opening having a diameter of between 1.0
mm and 2.0 mm. In an alternative embodiment the steam outlet can
comprise several steam outlet openings.
[0009] In a still further embodiment of a system for heating and
frothing a beverage according to the invention the froth wand
comprises a porous element adjacent the steam outlet. It has
appeared that frothing can be influenced by providing a porous
element in the steam outlet and such a porous element can thus be
used to adapt the frothing to at least some extent to the
preference of a user.
[0010] In an advantageous embodiment of a system for heating and
frothing a beverage according to the invention the steam channel
has a diameter of between 4 mm and 10 mm. In this manner heating of
frothing of a beverage can be realized effectively.
[0011] In a further embodiment of a system for heating and frothing
a beverage according to the invention the tubular wall of the froth
wand has a thickness of between 0.4 and 0.6 mm, preferably a 0.5 mm
wall thickness. It has appeared that a froth wand with such a
relative small thickness can withstand the operational parameters
during use and furthermore can be manufactured with relative low
cost due to the relative low use of material.
[0012] When the froth wand is made of a material having a low
thermal mass in a range of 1 to 20 gram, a used froth wand (i.e. a
froth wand through which steam has passed) can be manually held at
least for a time sufficient for disposing the froth wand.
Preferably the length of the disposable froth wand is between 100
and 120 mm, in particular 110 mm.
[0013] In an embodiment of a system for heating and frothing a
beverage according to the invention the froth wand comprises a
blade at the steam outlet end. In this manner the froth wand can be
efficiently used as a stirrer in the prepared beverage. The blade
can be shaped either asymmetrical or symmetrical with regard to a
longitudinal axis of the tubular wall. In order to facilitate
stirring the froth wand can then comprise a grip at the steam inlet
end. Such a grip can then be shaped either asymmetrical or
symmetrical with regard to a longitudinal axis of the tubular
wall.
[0014] In a particular embodiment of a system for heating and
frothing a beverage according to the invention the froth wand
comprises an upper flange at the steam inlet end. In this manner it
is possible that a froth wand holder is used for holding the froth
wand which is mechanically simple but still very reliable. It is
then especially advantageous when the upper flange has a flat end
face and/or when the froth wand comprises a retention flange spaced
at a distance from the top flange. In addition, such flange(s)
provide additional rigidity to the froth wand.
[0015] In a further embodiment of a system for heating and frothing
a beverage according to the invention an outside diameter of the
tubular wall increases from the steam outlet end towards the steam
inlet end. Alternatively the tubular wall can comprise a portion
extending from the steam inlet end, which portion has a decreasing
outside diameter. With such froth wands it is possible to use froth
wand holders for holding the froth wand which are mechanically
simple but still very reliable.
[0016] In a still further embodiment of a system for heating and
frothing a beverage according to the invention the tubular wall of
the froth wand comprises an air opening, preferably an air slot
extending parallel to a longitudinal axis of the tubular wall. In
this manner a more consistent flow of steam through the steam
channel can be obtained.
[0017] In an advantageous embodiment of a system for heating and
frothing a beverage according to the invention the froth wand
comprises a circulation channel provided on the tubular wall near
the steam outlet end of the froth wand, said circulation channel
having an intake opening and a separate outlet opening which latter
is positioned adjacent the steam outlet, said circulation channel
being preferably substantially parallel to the steam channel of the
froth wand. In this manner a circulation of steam and milk in the
circulation channel can be realized for more efficiently heating
and frothing the beverage milk. The circulation channel can be
formed by an addition tube arranged on the tubular wall near the
steam outlet end of the froth wand or by a coaxial circulating
sleeve forming the circulation channel between the inner wall of
the circulating sleeve and the outer wall of the froth wand.
[0018] In an embodiment of a system for heating and frothing a
beverage according to the invention wherein the froth wand holder
is arranged for holding the froth wand in a substantially vertical
position in the operational position the system can be configured
in a rather compact manner having a small footprint. Preferably the
froth wand holder is movably mounted in the device for heating and
frothing a beverage for being displaced from the operational
position to a froth wand insertion position, and vice versa. By
using a moveable froth wand holder the system can be arranged to be
used very safely. In a particular advantageous embodiment the froth
wand holder is then rotatable or tiltable.
[0019] Although the system can be arranged for moving the froth
wand holder automatically from the froth wand insertion position to
the operational position the user of the system can receive a
correct and immediate indication that the froth wand holder is in
the operational position when the froth wand holder comprises a
handle for manually displacing the froth wand holder. In this
manner the safety of the system is further improved.
[0020] In a further embodiment of a system for heating and frothing
a beverage according to the invention the froth wand holder
comprises a horizontal seat for holding the froth wand. In this
manner it is possible to construct the froth wand holder in a
relative simple manner while till providing reproducible and
correct holding of a froth wand. Inserting the froth wand in the
froth wand holder can be realized in an easy manner when the
horizontal seat comprises a froth wand opening for receiving a part
of the froth wand. In case the horizontal seat comprises a radial
slot opening into the froth wand opening the froth wand can be
positioned in the froth wand opening from the side of the from wand
holder.
[0021] In a still further embodiment of a system for heating and
frothing a beverage according to the invention the froth wand
holder comprises a clamping mechanism for clamping the froth wand.
In this manner it is possible to prevent that the froth wand is
removed from the froth wand holder unintentionally, e.g. during
heating and frothing a beverage.
[0022] A reproducible and correct clamping of a froth wand in a
froth wand holder can be realized in an embodiment of a system for
heating and frothing a beverage according to the invention wherein
the clamping mechanism comprises a movable engagement part,
arranged for being displaced from an idle position at least partly
protruding into the froth wand opening to an activating position
outside the froth wand opening, said clamping mechanism further
comprising a movable clamping part coupled to said displaceable
engagement part, said movable clamping part being coupled to said
displaceable engagement part such that the clamping part is
positioned into a releasing position for releasing or receiving the
froth wand when the engagement part is in the idle position and
such that the clamping part is positioned in a clamping position
for clamping the froth wand when the engagement part is in the
activating position. Alternatively the device for heating and
frothing a beverage can comprise a clamping activator, wherein the
clamping mechanism comprises a movable clamping part, said movable
clamping part being positioned in a releasing position for
receiving or releasing the froth wand when the froth wand holder is
in the froth wand insertion position, said clamping part
cooperating with the clamping activator when the froth wand holder
is in the operating position so at to be displaced into a clamping
position for clamping the froth wand.
[0023] Although the froth wand can be removed from the froth wand
holder when the holder is in the froth wand insertion position or a
separate froth wand removal position, the safety of use of the
system for heating and frothing a beverage according to the
invention can be further improved when the froth wand holder
comprises a froth wand ejector for ejecting the froth wand out of
the froth wand holder. In this manner it is additionally clear for
the user that heating and frothing a beverage is completed when the
froth wand is ejected by the froth wand ejector. Preferably, the
froth wand ejector is arranged for ejection the froth wand through
the radial slot.
[0024] In an embodiment of a system for heating and frothing a
beverage according to the invention a froth wand is ejected in a
reliable and mechanically simple manner when the froth wand ejector
comprises a spring actuated ejector arm, said spring being loaded
when the froth wand holder is displaced from the froth wand
insertion position into the operating position and released for
actuating the ejector arm when the froth wand holder is displaced
from the operating position into the froth wand insertion
position.
[0025] In an advantageous embodiment of a system for heating and
frothing a beverage according to the invention the froth wand
holder comprises a lid which is mounted displaceable relative to
the horizontal seat.
[0026] In a further embodiment of a system for heating and frothing
a beverage according to the invention the steam conduit comprises
an air inlet. In this manner a more consistent flow of steam
through the steam channel can be obtained. Preferably the device
for heating and frothing a beverage then comprises an air pump, in
particular a diaphragm pump, connected to the air inlet via an
active air inlet tube for introducing air into the flow of steam.
To improve the consistency of the flow of steam the active air
inlet tube comprises an air orifice.
[0027] In a still further embodiment of a system for heating and
frothing a beverage according to the invention the steam conduit
comprises a passive air inlet and the air pump is connected to an
active air inlet, wherein the device for heating and frothing a
beverage comprises a valve displaceable in a respective connection
position for either connecting the steam conduit to the passive air
inlet or the active air inlet. In this manner it is possible to
select the introduction of air into the steam via the passive air
inlet or the active air inlet, for example depending on the
beverage to be prepared or the preference of the user.
[0028] In a particularly advantageous embodiment of a system for
heating and frothing a beverage according to the invention the
device for heating and frothing a beverage comprises a reservoir
for cold water, preferably a separate reservoir for cold water, a
cold water conduit and a cold water pump for supplying cold water
to the steamer.
[0029] In an embodiment of a system for heating and frothing a
beverage according to the invention the steam nozzle is movably
mounted in the device for heating and frothing a beverage. It is
then possible to provide an embodiment of a system for heating and
frothing a beverage according to the invention wherein the steam
nozzle is dimensioned to be received in the steam channel of the
froth wand. In this manner the operation of the system can be
relatively simple in that the froth wand can be positioned in the
froth wand holder first and thereafter the steam nozzle can be
moved into the steam channel for supplying steam into the steam
channel. In order to improve the supply of steam into and through
the steam channel of the froth wand the steam nozzle comprises a
seal for sealing against an inner surface of the tubular wall
enclosing the steam channel.
[0030] In a further embodiment of a system for heating and frothing
a beverage according to the invention the device for heating and
frothing a beverage additionally comprises a liquid coffee
dispenser for dispensing liquid coffee as at least part of said
beverage. In this manner the liquid coffee can e.g. be dispensed
into a cup and the device for heating and frothing a beverage can
be used to heat and froth the liquid coffee via the froth wand.
Additionally, before, during or after the liquid coffee has been
dispensed into the cup another beverage, such as for example milk,
can be poured into the cup and the device for heating and frothing
can be used to supply steam into the milk or coffee or milk/coffee
mixture via the froth wand. Please note that the liquid coffee
dispenser can comprise a water reservoir which preferably is
additional to the cold water reservoir connected to the
steamer.
[0031] In a preferred embodiment of a system for heating and
frothing a beverage according to the invention the device for
heating and frothing a beverage comprises a controller
operationally connected to the steamer for controlling the
operation of the steamer. This controller can be operationally
connected to the air pump for controlling the operation of the air
pump and/or operationally connected to the cold water pump for
controlling the operation of the cold water pump and/or
operationally connected to the valve for positioning the valve in a
respective connecting position and/or operationally connected to
the froth wand ejector for either activating or deactivating the
froth wand ejector.
[0032] In a still further embodiment of a system for heating and
frothing a beverage according to the invention the device for
heating and frothing comprises a froth wand holder detector for
detecting whether the froth wand holder is positioned in the
operating position, said froth wand holder detector being
operationally connected to the controller for supplying a signal to
the controller indicative for whether the froth wand holder is
positioned in the operating position or not, said controller being
arranged for deactivating the froth wand ejector when the signal
received from the froth wand holder detector indicates that the
froth wand holder is in the operating position. In this manner the
safety of use of the system can be improved further. Preferably,
the froth wand holder detector is further arranged for detecting
whether the froth wand holder is positioned in the froth wand
insertion position, said froth wand holder detector being
operationally connected to the controller for supplying a signal to
the controller indicative for whether the froth wand holder is
positioned in the froth wand insertion operating position or not,
said controller being arranged for activating the froth wand
ejector when the signal received from the froth wand holder
detector indicates that the froth wand holder is in the froth wand
insertion position and the controller has deactivated the steamer
within a predetermined time period before receiving said signal
from the froth wand holder detector. In this manner it is possible
to discriminate the situation in which the froth wand is positioned
in the froth wand holder before the steamer is activated and after
the steamer has been activated, i.e. the beverage has been heated
and frothed.
[0033] To improve safety of use even further the controller is
arranged for automatically deactivating a component to which it is
operationally connected when the signal from the froth wand holder
detector indicates that the froth wand holder is in the froth wand
insertion position. Preferably the controller is arranged for
activating a component to which it is operationally connected only
when the signal from the froth wand holder detector indicates that
the froth wand holder is in the operating position.
[0034] In an embodiment of a system for heating and frothing a
beverage according to the invention the device for heating and
frothing a beverage includes a froth wand presence detector for
detecting whether a froth wand is held in the froth wand holder,
said froth wand presence detector being operationally connected to
the controller for supplying thereto a froth wand presence signal
indicative of whether or not a froth wand is held in the froth wand
holder. In this manner it can be prevented that the system is
activated in the situation that no froth wand is held by the froth
wand holder even in case the froth wand holder is in the
operational position. In addition it is then preferred when the
controller is arranged for controlling the component which is
operationally connected to it at least in dependence of the froth
wand presence signal.
[0035] In an advantageous embodiment of a system for heating and
frothing a beverage according to the invention the system for
heating and frothing a beverage comprises a cup support for a cup,
said froth wand holder and support being mutually arranged such
that the froth wand held in the froth wand holder extends into a
cup positioned on the support in the operational position of the
froth wand holder. In this manner a user does not need to hold the
cup himself or herself while the beverage is heated and frothed and
can positioned the cup on the cup support. Preferably the support
comprises position indicators indicating a central position of the
cup in which central position the froth wand extends substantially
centrally into the cup. Alternatively or additionally the support
can comprise position indicators indicating a off centre position
of the cup in which off centre position the froth wand extends
substantially off centre into the cup. Such indicators can be
formed by indentations or elevations or visual marks. In this
manner the user can choose the position in the cup into which the
froth wand extends and thus effect the manner in which the beverage
is frothed.
[0036] In a further embodiment of a system for heating and frothing
a beverage according to the invention the device for heating and
frothing a beverage comprises a froth temperature sensor for
sensing a temperature of froth in the cup, said temperature sensor
being operationally connected to said controller for supplying
thereto a signal indicative for the measured froth temperature. In
this manner the controller can e.g. deactivate the steamer when the
required or set temperature has been reached thereby using no more
energy then required. It is then in particular advantageous when
the froth temperature sensor comprises at least one microphone,
which preferably is positioned above the cup, beside the cup above
the upper edge of the cup or beside the cup below the upper edge of
the cup.
[0037] In a still further embodiment of a system for heating and
frothing a beverage according to the invention the froth wand
comprises a fill indication mark. Such a fill indication mark can
e.g. be a minimum fill level to ensure that a cup is filled with a
sufficient amount so that the steam outlet extends to below the
liquid level. Alternatively or additionally the fill indication
mark can be a proposed fill indication, meaning that a beverage
which is filled into a cup into which the froth wand extends up to
the proposed fill indication mark can be heated and frothed in a
generally accepted manner. Further an additional maximum fill
indication mark can be provided which ensures that a beverage
poured into a cup up to this maximum fill indication mark does not
flow over the edge of the cup when the beverage is heated and
frothed.
[0038] The invention further relates to a device for heating and
frothing a beverage suitable for being used in a system for heating
and frothing a beverage according to the invention, wherein said
device for heating and frothing a beverage includes a steamer, a
steam conduit connecting the steamer to a steam nozzle and a froth
wand holder for removably holding a disposable froth wand, said
froth wand holder being arranged for holding the disposable froth
wand at least in an operational position in the device for heating
and frothing a beverage. For redundancy reasons only the
embodiments of a device for heating and frothing a beverage are
described, the respective advantageous effects of the device for
heating and frothing a beverage are not mentioned in the following
in detail. However, reference is made to the before-mentioned,
wherein all features mentioned as to be relevant or advantageous
with regard to the system for heating and frothing a beverage are
transferable to the device.
[0039] In an embodiment of a device for heating and frothing a
beverage according to the invention the froth wand holder is
arranged for holding a froth wand in a substantially vertical
position in the operational position.
[0040] In a further embodiment of a device for heating and frothing
a beverage according to the invention the froth wand holder is
movably mounted in the device for heating and frothing a beverage
for being displaced from the operational position to a froth wand
insertion position, and vice versa. The froth wand holder is then
preferably rotatable and preferably comprises a handle for manually
displacing the froth wand holder.
[0041] In a still further embodiment of a device for heating and
frothing a beverage according to the invention froth wand holder
comprises a horizontal seat for holding a froth wand. The
horizontal seat then preferably comprises a froth wand opening for
receiving a part of a froth wand. It is further preferred that the
horizontal seat comprises a radial slot opening into the froth wand
opening.
[0042] In another embodiment of a device for heating and frothing a
beverage according to the invention the froth wand holder comprises
a clamping mechanism for clamping a froth wand. Preferably the
clamping mechanism comprises a movable engagement part, arranged
for being displaced from an idle position at least partly
protruding into the froth wand opening to an activating position
outside the froth wand opening, said clamping mechanism further
comprising a movable clamping part coupled to said displaceable
engagement part, said movable clamping part being coupled to said
displaceable engagement part such that the clamping part is
positioned into a releasing position for releasing or receiving a
froth wand when the engagement part is in the idle position and
such that the clamping part is positioned in a clamping position
for clamping a froth wand when the engagement part is in the
activating position.
[0043] In a still further embodiment of a device for heating and
frothing a beverage according to the invention the device for
heating and frothing a beverage comprises a clamping activator,
wherein the clamping mechanism comprises a movable clamping part,
said movable clamping part being positioned in a releasing position
for receiving or releasing a froth wand when the froth wand holder
is in the froth wand insertion position, said clamping part
cooperating with the clamping activator when the froth wand holder
is in the operating position so at to be displaced into a clamping
position for clamping a froth wand.
[0044] In an advantageous embodiment of a device for heating and
frothing a beverage according to the invention the froth wand
holder van comprise a froth wand ejector for ejecting a froth wand
out of the froth wand holder. The froth wand ejector is then
preferably arranged for ejection a froth wand through the radial
slot. The froth wand ejector can comprise a spring actuated ejector
arm, said spring being loaded when the froth wand holder is
displaced from the froth wand insertion position into the operating
position and being released for actuating the ejector arm when the
froth wand holder is displaced from the operating position into the
froth wand insertion position.
[0045] In another favourable embodiment of a device for heating and
frothing a beverage according to the invention the froth wand
holder comprises a lid which is mounted displaceable relative to
the horizontal seat.
[0046] In a further embodiment of a device for heating and frothing
a beverage according to the invention the steam conduit comprises
an air inlet. The device for heating and frothing a beverage can
then comprise an air pump, in particular a diaphragm pump,
connected to the air inlet via an active air inlet tube. The active
air inlet tube preferably comprises an air orifice. In a still
further embodiment of a device for heating and frothing a beverage
according to the invention the steam conduit comprises a passive
air inlet and the air pump is connected to an active air inlet,
wherein the device for heating and frothing a beverage comprises a
valve displaceable in a respective connection position for either
connecting the steam conduit to the passive air inlet or the active
air inlet.
[0047] In another embodiment of a device for heating and frothing a
beverage according to the invention the device for heating and
frothing a beverage comprises a reservoir for cold water, a cold
water conduit and a cold water pump for supplying cold water to the
steamer. The steam nozzle is preferably movably mounted in the
device for heating and frothing a beverage. The steam nozzle can
further comprise a seal for sealing against an inner surface of a
tubular wall enclosing a steam channel of a froth wand.
[0048] In a still further embodiment of a device for heating and
frothing a beverage according to the invention the device for
heating and frothing a beverage comprises a liquid coffee dispenser
for dispensing liquid coffee as at least part of said beverage.
[0049] The device for heating and frothing a beverage preferably
comprises a controller operationally connected to the steamer for
controlling the operation of the steamer. This controller can be
operationally connected to the air pump for controlling the
operation of the air pump and/or operationally connected to the
cold water pump for controlling the operation of the cold water
pump and/or operationally connected to the valve for positioning
the valve in a respective connecting position and/or operationally
connected to the froth wand ejector for either activating or
deactivating the froth wand ejector. The device for heating and
frothing then preferably comprises a froth wand holder detector for
detecting whether the froth wand holder is positioned in the
operating position, said froth wand holder detector being
operationally connected to the controller for supplying a signal to
the controller indicative for whether the froth wand holder is
positioned in the operating position or not, said controller being
arranged for deactivating the froth wand ejector when the signal
received from the froth wand holder detector indicates that the
froth wand holder is in the operating position.
[0050] In a still further embodiment of a device for heating and
frothing a beverage according to the invention the froth wand
holder detector is further arranged for detecting whether the froth
wand holder is positioned in the froth wand insertion position,
said froth wand holder detector being operationally connected to
the controller for supplying a signal to the controller indicative
for whether the froth wand holder is positioned in the froth wand
insertion operating position or not, said controller being arranged
for activating the froth wand ejector when the signal received from
the froth wand holder detector indicates that the froth wand holder
is in the froth wand insertion position and the controller has
deactivated the steamer within a predetermined time period before
receiving said signal from the froth wand holder detector.
[0051] In another embodiment of a device for heating and frothing a
beverage according to the invention the controller is arranged for
automatically deactivating a component to which it is operationally
connected when the signal from the froth wand holder detector
indicates that the froth wand holder is in the froth wand insertion
position. The controller is in particular arranged for activating a
component to which it is operationally connected only when the
signal from the froth wand holder detector indicates that the froth
wand holder is in the operating position.
[0052] In an even further embodiment of a device for heating and
frothing a beverage according to the invention the device for
heating and frothing a beverage includes a froth wand presence
detector for detecting whether a froth wand is held in the froth
wand holder, said froth wand presence detector being operationally
connected to the controller for supplying thereto a froth wand
presence signal indicative of whether or not a froth wand is held
in the froth wand holder. The controller can then be arranged for
controlling the component which is operationally connected to it at
least in dependence of the froth wand presence signal.
[0053] In a further embodiment of a device for heating and frothing
a beverage according to the invention the device for heating and
frothing a beverage comprises a support for a cup, said froth wand
holder and support being mutually arranged such that a froth wand
held in the froth wand holder extends into a cup positioned on the
support in the operational position of the froth wand holder. The
support can then comprise position indicators indicating a central
position of the cup in which central position a froth wand extends
substantially centrally into a cup and/or position indicators
indicating a off centre position of a cup in which off centre
position a froth wand extends substantially off centre into the
cup.
[0054] In a still further embodiment of a device for heating and
frothing a beverage according to the invention the device for
heating and frothing a beverage comprises a froth temperature
sensor for sensing a temperature of froth in a cup, said
temperature sensor being operationally connected to said controller
for supplying thereto a signal indicative for the measured froth
temperature. The froth temperature sensor can comprise at least one
microphone.
[0055] The invention further relates to a froth wand suitable for
being used in a system for heating and frothing a beverage
according to the invention, wherein the froth wand is a disposable
froth wand comprising a tubular wall having a steam inlet end
comprising a steam inlet, a steam outlet end comprising a steam
outlet separate from the steam inlet and a steam channel extending
between the steam inlet and the steam outlet. For redundancy
reasons only the embodiments of a froth wand are described, the
respective advantageous effects of the froth wand are not mentioned
in the following in detail. However, reference is made to the
before-mentioned, wherein all features mentioned as to be relevant
or advantageous with regard to the system for heating and frothing
a beverage are transferable to the froth wand. The disposable froth
wand is preferably made of biodegradable material.
[0056] In an embodiment of a froth wand according to the invention
the steam outlet extends radially through the tubular wall. The
steam outlet can be arranged at a free end of the froth wand
extending in longitudinal direction. The steam outlet preferably is
a circular opening having a diameter of between 1.0 mm and 2.0 mm.
The steam outlet can comprise more outlet openings.
[0057] In a further embodiment of a froth wand according to the
invention the froth wand comprises a porous element adjacent the
steam outlet. The steam channel preferably has a diameter of
between 4 mm and 10 mm, and the tubular wall of the froth wand can
have a thickness of between 0.4 and 0.6 mm, preferably a 0.5 mm
wall thickness.
[0058] In a still further embodiment of a froth wand according to
the invention the froth wand is made of a material having a low
thermal mass in a range of 1 to 20 gram. The length of the
disposable froth wand can be between 100 and 120 mm, preferably 110
mm.
[0059] In another embodiment of a froth wand according to the
invention the froth wand comprises a blade at the steam outlet end.
The blade can be shaped asymmetrical or symmetrical with regard to
a longitudinal axis of the tubular wall. Preferably the froth wand
comprises a grip at the steam inlet end. The grip can be shaped
asymmetrical or asymmetrical with regard to a longitudinal axis of
the tubular wall.
[0060] In a still further embodiment of a froth wand according to
the invention the froth wand comprises an upper flange at the steam
inlet end. The upper flange then preferably has a flat end face.
The froth wand can comprise a retention flange spaced at a distance
from the top flange.
[0061] In an embodiment of a froth wand according to the invention,
wherein an outside diameter of the tubular wall increases from the
steam outlet end towards the steam inlet end. Alternatively the
tubular wall can comprise a portion extending from the steam inlet
end, which portion has a decreasing outside diameter.
[0062] In another embodiment of a froth wand according to the
invention the tubular wall of the froth wand comprises an air
opening, preferably an air slot extending parallel to a
longitudinal axis of the tubular wall.
[0063] In an advantageous embodiment of a froth wand according to
the invention the froth wand comprises a circulation channel
provided on the tubular wall near the steam outlet end of the froth
wand, said circulation channel having an intake opening and a
separate outlet opening which latter is positioned adjacent the
steam outlet, said circulation channel being preferably
substantially parallel to the steam channel of the froth wand. In
this manner a circulation of steam and milk in the circulation
channel can be realized for more efficiently heating and frothing
the beverage milk. The circulation channel can be formed by an
addition tube arranged on the tubular wall near the steam outlet
end of the froth wand or by a coaxial circulating sleeve forming
the circulation channel between the inner wall of the circulating
sleeve and the outer wall of the froth wand.
[0064] In a specific embodiment of a froth wand according to the
invention the froth wand comprises a fill indication mark.
[0065] The invention still further relates to a method of preparing
a beverage using a system for heating and frothing a beverage
according to the invention, wherein the method comprises the step
of positioning a froth wand in the froth wand holder of the device
for heating and frothing a beverage such that the froth wand is
held in the froth wand holder in a substantially vertical position,
the step of activating the device for heating and frothing a
beverage when the froth wand holder is in the operational position
in the device for heating and frothing a beverage in which
operational position the steam nozzle is in communication with the
steam inlet of the froth wand, the step of supplying steam to and
through the froth wand, the step of releasing the froth wand from
the froth wand holder after steam has passed a predetermined number
of times through the froth wand and the step of disposing the froth
wand. By disposing the froth wand after steam has passed a
predetermined number of times through the froth wand the method of
preparing a beverage can be performed in a hygienic manner.
[0066] Preferably the predetermined number of times is less than
five. Most preferred the predetermined number of times is one,
which means that the froth wand is only used once improving the
hygienic use even further. For redundancy reasons only the
embodiments of a method for preparing a beverage are described, the
respective advantageous effects of the method are not mentioned in
the following in detail. However, reference is made to the
before-mentioned, wherein all features mentioned as to be relevant
or advantageous with regard to the system for heating and frothing
a beverage are transferable to the method.
[0067] In an embodiment of a method for preparing a beverage
according to the invention the step of supplying steam is enabled
only after the froth wand is held in the froth wand holder.
[0068] In a further embodiment of a method of preparing a beverage
according to the invention the step of positioning a froth wand in
the froth wand holder of the device for heating and frothing a
beverage is performed when the froth wand holder is positioned in
the froth wand insertion position and the method further comprises
the step of displacing the froth wand holder from the froth wand
insertion position to the operational position and the step of
displacing the froth wand holder from the operational position to
the froth wand insertion position after the step of supplying steam
to and through the froth wand and before the step of releasing the
froth wand from the froth wand holder. The steps of displacing the
froth wand holder from the froth wand insertion position to the
operational position and vice versa then can include the step of
rotating the froth wand holder.
[0069] In another embodiment of a method of preparing a beverage
according to the invention the method further comprises the step of
clamping the froth wand at least in the operational position of the
froth wand holder. Preferably the step of clamping the froth wand
takes place automatically when the froth wand holder is displaced
from the froth wand insertion position to the operational position,
in this manner the safety of use of the method is further
improved.
[0070] In a still further embodiment of a method of preparing a
beverage according to the invention the method can comprise the
step of disabling supplying steam when the froth wand holder is in
the froth wand insertion position. Alternatively or additionally
supplying steam is enabled only when the froth wand holder is in
the operational position.
[0071] In an advantageous embodiment of a method for preparing a
beverage according to the invention the step of releasing the froth
wand from the froth wand holder is performed by the froth wand
ejector.
[0072] The method can further comprise the step of closing the lid
when the froth wand has been positioned in the opening of the froth
wand support and supplying steam can be enabled only after the lid
has been closed. The step of releasing the froth wand from the
froth wand holder can then be performed automatically by displacing
the lid away from the froth wand support.
[0073] In a still further embodiment of a method for preparing a
beverage according to the invention during the step of supplying
steam to and through the froth wand air is sucked into the steam.
It is then preferred when during the step of supplying steam to and
through the froth wand air is pumped into the steam. The step of
supplying steam can comprise the step of supplying cold water to
the steamer.
[0074] In a preferred embodiment of a method for preparing a
beverage according to the invention the method comprises the step
of displacing the steam nozzle into the steam inlet of the froth
wand when the froth wand is held in the froth wand holder before
the step supplying steam to and through the froth wand.
[0075] In another embodiment of a method for preparing a beverage
according to the invention the method can comprise the step of
detecting whether or not a froth wand is held in the froth wand
holder.
[0076] A beverage can be prepared relatively easy in an embodiment
of a method for preparing a beverage according to the invention in
which the method comprises the step of placing a cup below the
froth wand holder before a froth wand is positioned in the froth
wand holder. The method then preferably comprises the step of
filling the cup with a first beverage, such as milk. During the
step of filling the cup with a first beverage the cup can be filled
up to the fill indication mark, such that the steam outlet of the
froth wand extends into the first beverage.
[0077] In an advantageous embodiment of a method for preparing a
beverage according to the invention the method comprises the step
of using a froth wand with a circulation channel provided on the
tubular wall near the steam outlet end of the froth wand, said
circulation channel having an intake opening and a separate outlet
opening which latter is positioned adjacent the steam outlet, said
circulation channel being preferably substantially parallel to the
steam channel of the froth wand, the method further comprises the
step of positioning the circulation channel in the beverage such as
to realize circulation of the beverage in the circulation channel.
In this manner a more efficient heating and frothing the beverage
milk can be obtained.
[0078] A versatile method for preparing a beverage according to the
invention can be obtained in case the method comprises the step
adding a second beverage into the cup after steam has been passed
through the froth wand into the first beverage. The method then
preferably comprises the step adding a second beverage into the cup
before, during or after steam has been passed through the froth
wand into the first beverage. In particular the second beverage is
coffee and the first beverage is milk.
[0079] In a further embodiment of a method for preparing a beverage
according to the invention the method comprises the step of using
the froth wand as stirrer after the froth wand has been
released.
[0080] An embodiment of a method for preparing a beverage
preferably comprises the step of positioning the cup such that the
froth wand extends substantially centrally or off center into the
cup.
[0081] A further embodiment of a method for preparing a beverage
according to the invention comprises the step of measuring the
temperature of the froth in the cup. The step of measuring the
temperature of the froth then preferably comprises the step of
recording sound from the froth and the step of deriving the
temperature from the recorded sound.
BRIEF DESCRIPTION OF DRAWINGS
[0082] Further features and advantages of the present invention
will appear from reading the description which follows, provided by
way of non-limiting example and with reference to the accompanying
drawings, in which:
[0083] FIG. 1 schematically shows an embodiment of a system for
heating and frothing according to the invention in front view
partly broken away;
[0084] FIG. 2 schematically shows a part of the embodiment of FIG.
1 in side view with a cup placed on a cup support;
[0085] FIGS. 3A-3L schematically show the steps of a method of
preparing a beverage by heating and frothing a beverage using the
system of FIGS. 1 and 2;
[0086] FIGS. 4A-4G schematically show a disposable froth wand
according to the invention with a radially extending steam outlet,
with the froth wand shown in several positions in a cup;
[0087] FIGS. 5A-5F schematically show a disposable froth wand
according to the invention with a longitudinally extending steam
outlet, with the froth wand shown in several positions in a
cup;
[0088] FIG. 6 schematically shows an embodiment of a system
according to the invention in which the device for heating and
frothing a beverage comprises an active air inlet tube and an air
pump for introducing air into the steam conduit;
[0089] FIG. 7 schematically shows an embodiment of a system
according to the invention in which the device for heating and
frothing a beverage comprises a steam conduit with a passive air
inlet for introducing air into the steam conduit;
[0090] FIGS. 8A-8C schematically show an embodiment of a system
according to the invention in which the device for heating and
frothing a beverage comprises a valve displaceable in a respective
connection position for either connecting the steam conduit to a
passive air inlet or an active air inlet for introducing air into
the steam conduit;
[0091] FIGS. 9A-9G schematically show several embodiments of a
froth wand according to the invention;
[0092] FIGS. 10A and 10B schematically show an embodiment of a
system according to the invention comprising a froth wand holder
positioned in the froth wand insertion position with a froth wand
opening for receiving a froth wand;
[0093] FIGS. 11A and 11B schematically show an embodiment of a
system according to the invention comprising a froth wand holder
positioned in the froth wand insertion position in which the
horizontal seat of the froth wand holder comprises a radial slot
opening into the froth wand opening;
[0094] FIGS. 12A-12E schematically show an embodiment of a system
according to the invention comprising a rotatable froth wand holder
comprising a handle for manually displacing the froth wand holder
and a froth wand ejector;
[0095] FIGS. 13A-13C schematically show several embodiments of a
froth wand according to the invention with different configurations
at the steam inlet end;
[0096] FIGS. 14A-14D schematically show an embodiment of a system
according to the invention in which the froth wand holder comprises
froth wand clamping means and in which the steam nozzle is
configured to be introduced and received in the steam channel of
the froth wand;
[0097] FIG. 15 schematically shows a first embodiment of the system
according to the invention in which the interconnection between
constituting components is shown schematically;
[0098] FIG. 16 schematically shows a second embodiment of the
system according to the invention in which the interconnection
between constituting components is shown schematically, and
[0099] FIG. 17 schematically shows a part of an embodiment of a
system according to the invention comprising a microphone as
temperature sensor indicating the microphone positions.
[0100] In FIG. 1 an embodiment of a system 1 for heating and
frothing according to the invention is schematically shown in front
view partly broken away. The system 1 comprises a device 2 for
heating and frothing a beverage and a froth wand 3.
[0101] The device 2 includes a steamer 4, for example a
thermo-block, a steam conduit 5 connecting the steamer 4 to a steam
nozzle 6. A reservoir 7 for cold water 8 is provided in the device
2, which cold water reservoir 7 is connected to the steamer 4 via a
cold water conduit 9 and a cold water pump 10 for supplying cold
water to the steamer 4.
DETAILED DESCRIPTION
[0102] In the embodiment shown in FIG. 1 the device 2 further
comprises a liquid coffee dispenser 11 for dispensing liquid
coffee. In the shown embodiment the liquid coffee dispenser 11
comprises a chamber 12 for receiving a package 13 of concentrated
liquid coffee. The liquid coffee dispenser 11 further comprises a
coffee dosing apparatus 14 for dosing an amount of concentrated
liquid coffee into a mixing chamber 15. Heated water is supplied
from a water heater 16 via a water conduit 17 to the mixing chamber
15 to dilute the concentrated liquid coffee to a liquid coffee
having a more consumable concentration. This liquid coffee can be
dispensed into a cup (not shown in FIG. 1) from a liquid coffee
outlet 18. In the shown embodiment the water heater 16 is supplied
with cold water from the cold water reservoir 7 by means of the
cold water conduit 9 and an extension 9' thereof. In other
embodiments the water heater 16 can be supplied with water from a
water source separate from the cold water reservoir 7.
[0103] The device 2 further comprises a froth wand holder 19 for
removably holding the froth wand 3. The froth wand holder 19 is
arranged for holding the froth wand 3 at least in an operational
position (as shown in FIG. 2) in the device 2 in which the steam
nozzle 6 is in communication with a steam inlet 20 of the
disposable froth wand 3. The froth wand holder 19 comprises a
horizontal seat 29 for holding the froth wand 3. For this the
horizontal seat 29 has a froth wand opening 30 for receiving a part
of the froth wand 3. The froth wand holder 19 further comprises a
lid 31 which is mounted displaceable relative to the horizontal
seat 29, in the shown embodiment the lid 31 is mounted on a
rotation shaft 32 so that it can be rotated away from the seat 29
so that a froth wand 3 can be placed in the froth wand opening 30
or taken out therefrom (the so called froth wand insertion position
of the froth wand holder 19) or rotated towards the seat 29 to
enclose a froth wand 3 positioned in the froth wand holder 19 which
is then situated in the operational position.
[0104] The froth wand 3 is a disposable froth wand comprising a
tubular wall 21 having a thickness of between 0.4 and 0.6 mm,
preferably a 0.5 mm wall thickness, and having a steam inlet end 22
comprising the steam inlet 20, a steam outlet end 23 comprising at
least one steam outlet 24 separate from the steam inlet 20 and a
steam channel 25 having a diameter of between 4 mm and 10 mm
extending between the steam inlet 20 and the steam outlet 24. In
the embodiment shown in FIG. 2 the steam outlet 24 extends radially
through the tubular wall 21. Furthermore the tubular wall 21 of the
froth wand 3 comprises an air opening 36 extending through the
wall. In the shown embodiment the air opening is slot shaped, the
slot extending parallel to a longitudinal axis of the tubular wall
21. In other embodiments the air opening can be formed by one or
more round holes.
[0105] The disposable froth wand 3 is made of biodegradable
material, in particular a material having a low thermal mass in a
range of 1 to 20 gram.
[0106] In FIG. 2 it is further shown that the system 1, in
particular the device 2, comprises a support 26 for a cup 27, and
that the froth wand holder 19 and the support 26 are mutually
arranged such that the froth wand 3 held in the froth wand holder
19 extends into the cup 27 positioned on the support 26 in the
operational position of the froth wand holder. Indicated in FIG. 2
is further an amount of milk 28, as first beverage while the liquid
coffee is also called second beverage in this description, and that
the disposable froth wand 3 has a length between 100 and 120 mm,
preferably 110 mm, such that the steam outlet 24 is positioned
below the milk meniscus.
[0107] Referring to FIGS. 3A-3L a method of preparing a beverage by
heating and frothing using the system 1 of FIGS. 1 and 2 will be
described in the following.
[0108] In FIG. 3A the start or rest position of the device 2 is
shown in which the lid 31 is closed. To shorten the time period in
which the beverage can be prepared the steamer or thermo block 4 is
kept operative such that the water used for forming the steam is
kept at an idle temperature of about 90.degree. C. In the first
step shown in FIG. 3B the lid 31 is opened by rotation around the
rotation shaft 32 placing the froth wand holder 19 in the so-called
froth wand insertion position, and a cup 27 is placed on the
support 26. The system is arranged such that in this froth wand
insertion position supply of steam is disabled. In order to provide
a user with information where to place the cup 27 the support
comprises position indicators 33, such as e.g. visual markings,
indicating a central or off center position of the cup. A central
position means that when a froth wand is held in the froth wand
holder 19 the froth wand extends substantially centrally into the
cup, in the off center position the froth wand will extend off
center into the cup. In the second step shown in FIG. 3C a froth
wand 3 is placed in the froth wand opening 30 of the froth wand
holder 19 of the device 2 such that the froth wand 3 is held in the
froth wand holder 19 in a substantially vertical position. In
addition, in this so called operational position the steam nozzle 6
is in communication with the steam inlet 20 of the froth wand 3. In
the third step shown in FIG. 3D the lid 31 is closed. The lid 31
comprises sealing means 34 which provides a seal with the upper
edge of the froth wand 3 and in addition provides clamping of the
froth wand 3. Please note that the system is arranged such that
supplying steam is enabled only after the froth wand 3 is
positioned in the froth wand holder 19 and more preferably when the
lid 31 has been closed. In the fourth step shown in FIG. 3E the cup
27 is filled with a first beverage, such as milk 28, up to a fill
indication mark 35 provided on the froth wand 3, such that the
steam outlet 24 of the froth wand 3 extends into the milk 28.
[0109] In the fifth step as shown in FIG. 3F the steamer 4 is
activated and warms up the water further to produce steam which is
then supplied to and through the froth wand 3 and into the milk 28
via the steam outlet 24. During steam supply cold water is fed from
the cold water reservoir 7 (FIG. 1) to the steamer 4. During this
supply of steam to and through the froth wand 3 air is sucked into
the steam via the air slot 36. Supply of steam realizes the heating
and frothing of the milk 28 and takes in this embodiment place
during a predetermined period of time to sufficiently heat and
froth the milk 28. After the time period has elapsed the steamer 4
is deactivated in the sixth step as shown in FIG. 3G. Then in the
seventh step (FIG. 3H) the liquid coffee dispenser 11 is activated
and coffee as a second beverage different from the first beverage
is added into the cup 27 until the dosing of coffee is completed
(FIG. 3I). If desired by the user the steamer 4 can be activated
again to heat and froth the coffee/milk mixture. Please note that
in other embodiments the coffee can be dispensed into the cup and
optionally heated and frothed before the milk is poured into the
cup 27 and heated and frothed.
[0110] In the following step the lid 31 is opened (indicated by the
arrow in FIG. 3J) and finally reaches the froth wand insertion
position, thereby releasing the froth wand 3 from the froth wand
holder 19. Which in the shown embodiment can be manually taken out
of the froth wand holder 19 as shown in FIG. 3K. If desired the
froth wand 3 can be used as stirrer (FIG. 3L) after the froth wand
3 has been released and the user can consume the prepared beverage
and thereafter dispose of the froth wand 3.
[0111] In the embodiment shown in FIG. 3 the froth wand 3 is
disposed when it is used only once. Amongst others things dependent
on the frequency the system is used to heat and froth a beverage
the froth wand 3 can be used more than once but from a hygienic
point of view number of times a froth wand is used should
preferably be less than five.
[0112] In FIGS. 4A-4G schematically the disposable froth wand 3
with the radially extending steam outlet 24 of FIG. 3 is shown,
with the froth wand shown in several positions in which it can be
positioned relative to the cup 27. The steam outlet 24 has a
diameter of 1.5 mm, but can in other embodiments be between 1.0 mm
and 2.0 mm. In FIG. 4B the central position of the froth wand 3 in
the cup is indicated, while in FIGS. 4C and 4D the off center
position of the froth wand 3 relative to the cup 27 is indicated.
The radial extending slot 24 extends somewhat tangentially to the
cup wall as indicated in FIG. 4C and is directed to the wall as
indicated in FIG. 4D. In a not shown position the radial slot 24
can be directed to the center of the cup when the froth wand 3 is
positioned off center. Please note that the user can to some extent
influence frothing by adjusting the direction of the steam outlet
and thereby adjust the frothing to his or her desires. In case the
support 26 is adjustable in height (as indicated by the arrow 26')
in FIGS. 4F and 4G the user can to some extent influence frothing
by adjusting the height of the support and thus the depth in the
milk the froth wand, in particular the steam outlet 24, is
submerged, and thereby adjust the frothing to his or her desires.
In addition the system 1 can be provided with several supports each
having their own thickness to adjust the submersion depth of the
froth wand 3 in the milk. In addition, the froth wand 3 can be
tilted somewhat from the vertical position as shown in FIG. 4E to
direct the steam downwards into the milk. Please note that it is
also possible to realize this downwards direction of steam by
tilting the cup.
[0113] In FIGS. 5A-5F schematically another embodiment of a
disposable froth wand 3 is shown comprising a longitudinally
extending steam outlet 24, in this embodiment having a diameter of
1.5 mm, but the diameter can in other embodiments be between 1.0 mm
and 2.0 mm, with the froth wand 3 shown in several positions in
which it can be positioned relative to the cup 27. In FIG. 5B the
central position of the froth wand 3 in the cup is indicated, while
in FIG. 5C the off center position of the froth wand 3 relative to
the cup 27 is indicated. In case the support 26 is adjustable in
height (as indicated by the arrow 26') in FIGS. 5E and 5F the user
can to some extent influence frothing by adjusting the height of
the support and thus the depth in the milk the froth wand, in
particular the steam outlet 24, is submerged, and thereby adjust
the frothing to his or her desires. In addition the system 1 can be
provided with several supports each having their own thickness to
adjust the submersion depth of the froth wand 3 in the milk. In
addition, the froth wand 3 can be tilted somewhat from the vertical
position as shown in FIG. 5D to direct the steam downwards into the
milk. Please note that it is also possible to realize this
downwards direction of steam by tilting the cup.
[0114] In the embodiment shown in FIG. 3 air is introduced into the
steam via the air inlet 36 of the froth wand 3 to provide a more
consistent flow of steam. However, in other embodiments air can
already be introduced in the steam in the device 2 as will be shown
in FIGS. 6 to 8. Please note that for convenience of drawing steam
nozzle has been left out in these figures and thus the steam
conduit 5 is shown as directly engaging the froth wand 3. It will
be clear however that it is the steam nozzle that engages the froth
wand.
[0115] In FIG. 7 the steam conduit 5 can provided with a (passive)
air inlet 37, e.g. formed by a venture, a hole or a slot in the
steam conduit 5, so that air can be sucked into the steam conduit 5
when steam is being passed therethrough.
[0116] In the embodiment shown in FIG. 6 the device comprises an
air pump 38 (such as a diaphragm pump) connected to the air inlet
37 via an active air inlet tube 39, comprising an air orifice 40.
In this manner air can be actively pumped into the steam via the
steam inlet 37.
[0117] In the embodiment shown in FIGS. 8A-C the steam conduit 5
may comprises a passive air inlet 41 as well as an air pump 38
connected to an active air inlet 42, and a valve 43 displaceable in
a respective connection position for either connecting the steam
conduit 5 to the passive air inlet 41 (FIG. 8C) or the active air
inlet 42 (FIG. 8B).
[0118] In the embodiment shown in FIG. 3 air is introduced into the
steam via the air inlet 36 of the froth wand 3 to provide a more
consistent flow of steam which is dispensed into the milk by a
radially extending steam outlet 24. In FIG. 5 an alternative froth
wand 3 is indicated comprising a longitudinally extending steam
outlet, and in FIG. 9A this froth wand 3 is shown with the air
slot. In FIGS. 9A-9G and 13A-13C schematically several embodiments
of a froth wand are shown which can be used.
[0119] In the embodiment shown in FIG. 9B the froth wand 3
comprises a porous element 44 adjacent the steam outlet 24 and in
the shown embodiment with a coaxial circulating sleeve 45 forming a
circulation channel (as shown preferably substantially parallel to
the steam channel of the froth wand) between the inner wall of the
sleeve 45 and the outer wall of the froth wand 3 for realizing a
circulation of steam and milk in the circulation channel as
indicated by the arrows for more efficiently heating and frothing
the beverage milk. Please note that since the circulating sleeve 45
is provided at the end of the froth wand 3 it can be easily
submerged into to milk for obtaining a circulation during
operation. The circulating sleeve 45 can of course also be used in
embodiment without the porous element 44. Air is introduced in the
steam by the air slot 36 in the froth wand 3, but can alternatively
or additionally be introduced in the steam conduit of the
device.
[0120] In the embodiment shown in FIG. 9C an air addition tube 46
is arranged on the tubular wall 21 near the steam outlet end 24 of
the froth wand 3. The air addition tube 46 has an air intake
opening 47 and an air outlet opening 48 separate from the steam
outlet 24 but positioned adjacent to the steam outlet 24. In one
embodiment of the invention during filling the cup with milk 28
care should be taken that the liquid level should not rise above
the air intake opening 47 of the air addition tube 46. This air
addition tube 46 can be used in place of the air slot 36 for
introducing air into the milk 28. In another embodiment however,
this air addition tube 46 can be used additional to the air slot 36
(indicated in phantom in FIG. 9C) for either introducing additional
air into the milk 28 or when the intake opening 47 is positioned
below the level of milk or during use comes when the level of milk
rises above the intake opening 47 to realize circulation of steam
and milk in the circulation channel formed between the inner wall
of the tube 46 and the outer wall of the froth wand 3 as indicated
by the arrows for more efficiently heating and frothing the
beverage milk.
[0121] In the embodiment shown in FIG. 9D the froth wand 3
comprises a central steam channel 25 and a coaxial tube 49
surrounding the tubular wall 21 and forming therewith an ring
shaped air channel 50 having an air intake opening 47 and an air
outlet opening 48. Please note that the air intake opening 47 in
this embodiment can optionally be connected to an air pump present
in the device 2.
[0122] In FIGS. 9E-9G embodiments of the froth wand 3 are shown
comprising a blade 51 at the steam outlet end 24 to improve
stirring. The blade 51 can be shaped asymmetrical (FIG. 9G) or
symmetrical (FIGS. 9E and 9F). The froth wand 3 shown in FIG. 9E
further comprises a grip 52, for example a symmetrical grip, for
gripping the froth wand 3 during stirring or a grip 53 (FIGS. 9F
and 9G), for example an asymmetrical grip, to facilitate placing
and removing the froth wand in and from the froth wand holder
respectively. The embodiments of the froth wand 3 as shown in FIGS.
9F and 9G as well as those shown in FIGS. 13A and 13B further
comprise an upper flange 53 at the steam inlet end by which the
froth wand 3 can be supported in the seat 29 of the froth wand
holder 19, wherein the upper flange 54 has a flat end face 54A for
providing a sealing surface. De pending on the construction of the
froth wand holder 19 in which the froth wand is to be held the
froth wand 3 can further comprise a retention flange 55 (FIGS. 9F,
9G and 13A) spaced at a distance from the top flange 54.
[0123] Although the outside diameter of the embodiments of the
froth wand as shown in FIGS. 9A-9D and 13A have a constant value
over its complete length it will be clear that in other embodiments
of a froth wand the outside diameter of the tubular wall can
increase from the steam outlet end towards the steam inlet end. In
the alternative embodiments shown in FIGS. 13B and 13C the tubular
wall 21 comprises at least one portion 56, 56A, 56B extending from
the steam inlet end in particular the upper flange 54 or free end
of the froth wand, which portion has a decreasing outside diameter.
This portion can be shaped such that it can be received without
play in a mating froth wand opening 30 of the froth wand holder
19.
[0124] In FIGS. 10, 11, 12 and 14 embodiment of a system or device
according are shown having alternative froth wand holder with
regard to the froth wand holder 19 shown in FIGS. 1 and 2 in which
the froth wand holder 19 is movably mounted in the device 2 for
heating and frothing a beverage for being displaced from the
operational position to the froth wand insertion position, and vice
versa.
[0125] In FIGS. 10A and 10B a froth wand holder 19 is shown
comprising a seat 19 with a froth wand opening 30. The froth wand
holder 19 is positioned in the froth wand insertion position
wherein the seat 29 with the froth wand opening 30 is situated
outside the housing 2A of the device 2. After placement of the
froth wand 3 in the froth wand opening 30 (FIG. 10B) the seat 29
can be pushed into the housing 2A. By means of a handle 57 the lid
31, which is now positioned within the housing, can be closed
analogous to the embodiment as shown in FIGS. 1-3.
[0126] In the embodiment of the froth wand holder 19 shown in FIG.
11A in the froth wand insertion position the seat 29 comprises a
radial slot 30A opening into the froth wand opening 30 so that a
froth wand can be placed in the froth wand opening by displacing it
from the side of the seat through the radial slot 30A. In this
embodiment the froth wand holder in particular the seat 29 is
rotatable from the froth wand insertion position to an operational
position in which the froth wand opening 30 (indicated by broken
lines) is not accessible from outside the device. Also in this
embodiment the froth wand holder can comprise a handle 57 for
manually displacing the lid of the froth wand holder. In the
embodiment shown in FIG. 11B a froth wand can be inserted into the
radial slot 30A from the front of the device 2. In this embodiment
the lid 31 can be housed in a chamber portion 2B which is either
fixed relative to the housing of the device or can be movable as
indicated by the arrow. Also in this embodiment the froth wand
holder can comprise a handle 57 for manually displacing the lid of
the froth wand holder.
[0127] In the embodiment as shown in FIGS. 1 to 3 the froth wand is
clamped by the seal 34 as the lid 31 is closed, in this manner
sealing and clamping are performed by the same component. It will
however be clear for a person skilled in the art that the froth
wand holder can comprise any other known clamping mechanism for
clamping the froth wand separate from sealing the froth wand. An
exemplary embodiment of such a clamping mechanism 58 is disclosed
in FIG. 14B. The clamping mechanism 58 comprises a movable
engagement part 59, arranged for being displaced from an idle
position at least partly protruding into the froth wand opening 30
(indicated by the solid line) to an activating position 59' outside
the froth wand opening indicated by broken lines. The clamping
mechanism 58 further comprises two movable clamping arms or parts
60, 60A coupled to said displaceable engagement part 59, 59' and
are in the shown embodiment coupled together via a rotation shaft
61. The movable clamping part 59 is coupled to the arms 60, 60A
such that the arms 60, 60A of the clamping part is positioned into
a releasing position RP for releasing or receiving the froth wand
when the engagement part is in the idle position and such that the
clamping part is positioned in a clamping position CP for clamping
the froth wand when the engagement part is in the activating
position i.e. when the engagement part 59A is engaged by the froth
wand and pushed inward by inserting the froth wand into the froth
wand opening. In stead of using the froth wand itself as operator
for activating the clamping mechanism, the device 2 can comprise a
separate clamping activator, which positions the clamping mechanism
in either a releasing position for receiving or releasing the froth
wand or a clamping position for clamping the froth wand. Such a
clamping activator preferably is formed by the handle 57 or the lid
31 which is used to move the froth wand holder from the froth wand
insertion position to the operational position and can be used for
simultaneously and automatically displacing the clamping mechanism
from the releasing position into the clamping position when it
moves the froth wand holder from the froth wand insertion position
to the operational position. In particular the clamping mechanism
is arranged for clamping the froth wand at least in the operational
position.
[0128] In the exemplary embodiment of the froth wand holder 19 as
shown in FIGS. 12A-12E the froth wand holder 19 also comprises a
seat 29 with a radial slot 30A opening into the froth wand opening
30 so that a froth wand can be placed in the froth wand opening by
displacing it from the front of the seat through the radial slot
30A. In this embodiment the froth wand holder in particular the
seat 29 is rotatable from the froth wand insertion position (shown
in FIGS. 12A and B) to an operational position (shown in FIG. 12C)
in which the froth wand opening 30 is not accessible from outside
the device. The froth wand holder 19 comprises a handle 57' for
manually rotating the seat 29 of the froth wand holder 19. In this
embodiment the froth wand holder 19 comprises a froth wand ejector
62 for ejecting the froth wand 3 out of the froth wand holder 19.
In the shown embodiment the froth wand ejector 62 is arranged for
ejection the froth wand 3 through the radial slot 30A as will be
explained below.
[0129] The seat 29 of the froth wand holder is mounted displaceable
from the froth wand insertion position shown in FIG. 12D in which
the stop end 29A of the seat 29 is spaced from a stop surface 63 of
a seat guide 64 of the froth wand holder up to the operational
position in which the stop end 29A abuts the stop surface 63. This
displacement is effected by rotation of an upper seat part 29B
(FIG. 12E) which is rotatably mounted to the seat 29 via a centre
boss 29D. In the upper seat part 29B a slot 29E is provided in
which a slider 29C fixed to the seat 29 is received. Upon rotation
of the upper seat part 29B by operating on the handle 57' the side
edges of the slot 29D engage with the slider 29C as a result of
which the seat 29 is displaced as indicated by the arrow in FIG.
12D. The seat guide 64 of the froth wand holder 19 comprises two
cam tracks 65, 66 in which a boss 67 is received and can be
displaced during movement of the seat 29. The boss 67 is connected
to a rotation axis 69 via an arm 68 and the froth wand ejector 62
(shaped as an arm) is also rotatably connected to the rotation axis
69 and is loaded by a spring 70. In this manner the spring 70 is
loaded when the froth wand holder is displaced from the froth wand
insertion position into the operating position in which the boss 67
is guided in the track 65 and is released for actuating the ejector
arm 62 to eject the froth wand from the radial slot 30A when the
froth wand holder is displaced from the operating position into the
froth wand insertion position in which the boss 67 is guided in the
track 66. In this manner the froth wand is ejected automatically.
Please note that the system can be arranged such that the seat 29
can only be displaced from the operational position to the froth
wand insertion/releasing position after steam has been supplied
through the froth wand or upon a specific instruction thereto, e.g.
given by pressing a respective button suited therefore in order to
improve safety. Thus using such a device leads to a method of
preparing a beverage in which the step of positioning a froth wand
in the froth wand holder of the device for heating and frothing a
beverage is performed when the froth wand holder is positioned in
the froth wand insertion position, the step of displacing the froth
wand holder from the froth wand insertion position to the
operational position takes place by rotating the seat of the froth
wand holder by application of a handle, the step of displacing the
froth wand holder from the operational position to the froth wand
insertion position takes place only after steam is supplied to and
through the froth wand, where after the froth wand is released
automatically from the froth wand holder.
[0130] In the embodiment shown in FIGS. 1-3 the lid 31 comprises a
conduit 31A which ensures communication of the nozzle 6 (in the
shown embodiment extending horizontally) and the steam channel of
the froth wand in operational position. However, it will be clear
to a person skilled in the art that the invention is not limited to
such an embodiment and that the nozzle 6 can e.g. also be oriented
vertically. Such an embodiment is for example disclosed in FIGS.
14A-14D. In the embodiment shown in these FIGS. 14A-14D the steam
nozzle 6 is movably mounted in the device 2 for heating and
frothing a beverage. As follows from FIG. 14D the steam nozzle 44
is further dimensioned so that it can be received in the steam
channel 25 of the froth wand 3. The steam nozzle 6 comprises a seal
71 for sealing against an inner surface of the tubular wall
enclosing the steam channel. As shown in the Figures the steam
nozzle 44 is movable arranged within a guide tube 72 which is also
movably mounted. This guide tube 72 (part of the lid or as
replacement of the lid) is first lowered to seal against the upper
flange 54 of the froth wand and to provide clamping in addition to
the clamping realized by the clamping means 58 (FIG. 14C).
Thereafter the steam nozzle 6 is lowered into the steam channel of
the froth wand as indicated in FIG. 14D, where after steam can be
supplied to and through the steam nozzle and steam channel.
[0131] In FIG. 15 schematically a first embodiment of a schedule of
a system according to the invention is shown in which the
interconnection between constituting components is shown
schematically. The device of the system for heating and frothing a
beverage comprises a controller 73 which operationally connected to
the steamer 4 for controlling the operation of the steamer. In
addition the controller 73 is operationally connected to the air
pump for controlling the operation of the air pump and
operationally connected to the cold water pump 10 for controlling
the operation of the cold water pump and operationally connected to
the valve 43 for positioning the valve in a respective connecting
position. In case an electromagnetically controlled froth wand
ejector is used the controller 73 is also operationally connected
to the froth wand ejector for either activating or deactivating the
froth wand ejector. The system further comprises the following
shelf components: a non-return valve 74, an air restrictor 75, a
duck-bill valve 76, an additional thermo block 77 and a steam
delivery valve 78, a water flow meter 79, a steam dump valve 80, a
condenser 81 and a steam charge valve 82. In the second schedule
embodiment shown in FIG. 16 additionally a steam pump 83 and a
pressure regulator 84 are enclosed in the depicted manner.
[0132] Both systems shown in FIGS. 15 and 16 further comprise a
froth wand holder detector 85 for detecting whether the froth wand
holder 19 is positioned in the operating position. This froth wand
holder detector 85 is operationally connected to the controller 73
for supplying a signal to the controller 73 indicative for whether
the froth wand holder 19 is positioned in the operating position or
not. The controller 73 is then arranged for deactivating the
(electromagnetically actuatable) froth wand ejector when the signal
received from the froth wand holder detector 85 indicates that the
froth wand holder 19 is in the operating position. The froth wand
holder detector 85 is further arranged for detecting whether the
froth wand holder 19 is positioned in the froth wand insertion
position and can supply a signal to the controller 73 indicative
for whether the froth wand holder 19 is positioned in the froth
wand insertion operating position or not. The controller 73 is then
arranged for activating the froth wand ejector when the signal
received from the froth wand holder detector 85 indicates that the
froth wand holder is in the froth wand insertion position and the
controller 73 has deactivated the steamer 4 within a predetermined
time period before receiving said signal from the froth wand holder
detector 85.
[0133] The controller 73 is arranged for automatically deactivating
a component to which it is operationally connected when the signal
from the froth wand holder detector 85 indicates that the froth
wand holder 19 is in the froth wand insertion position and/or
arranged for activating a component to which it is operationally
connected only when the signal from the froth wand holder detector
85 indicates that the froth wand holder is in the operating
position.
[0134] In the schedules of the systems shown in FIGS. 15 and 16 the
device further includes a froth wand presence detector 86 for
detecting whether a froth wand 3 is held in the froth wand holder
19. The froth wand presence detector 86 is operationally connected
to the controller 73 for supplying thereto a froth wand presence
signal indicative of whether or not a froth wand 3 is held in the
froth wand holder 19. The controller 73 is then arranged for
controlling the component which is operationally connected to it at
least in dependence of the froth wand presence signal.
[0135] In the schedules of the systems shown in FIGS. 15 and 16 the
system in particular the device further includes a froth
temperature sensor 87 for sensing a temperature of froth 28A in the
cup 27. The temperature sensor 87 is operationally connected to the
controller 73 for supplying thereto a signal indicative for the
measured froth temperature. The froth temperature sensor comprises
at least one microphone (see FIG. 17) which can be positioned above
(87A) the cup 27, beside (87B) the cup 27 above the upper edge 27A
of the cup 27 or beside (87C) the cup below the upper edge 27A of
the cup 27. Measuring the temperature of the froth 28A then
includes recording sound from the froth 28A and the step of
deriving the temperature from the recorded sound by means of a
suitable algorithm stored in the controller 73. Depending on the
measured temperature the controller 73 can then decide whether or
not to deactivate the steamer 4. The controller 73 therefore
controls the method of heating and frothing and preparing a
beverage based on information gathered by the respective sensors
79, 85, 86 and 87.
* * * * *