HK1208322B - Device for preparing hot or cold milk froth - Google Patents

Description

Device for preparing milk froth, optionally hot and cold, or for dispensing milk optionally hot and cold

Technical Field

The invention relates to a device for preparing milk froth, optionally hot and cold, or for dispensing milk, optionally hot and cold.

Background

According to the prior art, coffee-making appliances, in particular espresso machines, are often equipped with a milk froth preparation device which comprises as a main component a frothing device with a flow channel which is designed as a venturi nozzle. The flow channel is connected to a milk line into which an air intake line or an air intake opening can open in order to prepare milk froth. For preparing milk froth, steam is supplied from a steam generator of the coffee preparation appliance to a flow channel of the frothing device, which is designed as a venturi nozzle, and a negative pressure is generated by the flow of steam in the flow channel, which negative pressure sucks milk from the milk container via a milk line and air via an air supply. Thus, the steam, milk and air mix in the flow passage and generate hot milk froth. By blocking the air supply, the production of foam in the flow channel of the frothing device is stopped and only hot milk is prepared.

Recently, it has been required not only that hot milk froth can be produced by the apparatus for preparing milk froth, but also that cold milk froth can be output. For this purpose, cold milk is sucked from the storage container into the frothing unit by means of a delivery pump, and the air which causes frothing is sucked in via an air delivery line which opens into the milk line (in which an underpressure is formed due to the flow speed of the milk), or is delivered to the milk via an air line by the underpressure generated by the pump. The mixing of the milk with the air can take place already in the milk line or only in the milk frothing device.

It is also known to selectively generate hot or cold foam in such a milk foam production device. In order to produce hot milk froth or only hot milk, the milk fed by means of the pump or the milk-air mixture fed to the frothing device can be conducted through a heat exchanger upstream of the frothing device or in the frothing device.

In a device known in this way for producing milk foam or milk drinks, in which milk is sucked from a container by means of a pump and conveyed to a discharge opening, wherein the milk, air can be mixed and the resulting milk-air mixture can be processed in the cold or hot state into milk foam by means of a throttle valve, it is provided that the milk-air mixture is conveyed selectively to the discharge opening directly or via a continuous heater (WO 2008/083941 a 1). In particular, the discharge line arranged downstream of the pump has for this purpose two parallel sections arranged between the throttle point and the discharge opening, which are selectively connectable via a valve, wherein only one of these parallel sections is assigned a continuous heater. It is thus possible to convey cold or hot milk froth to the discharge opening. The device for producing milk froth or a milk beverage may be formed as a separate appliance or as an integral part of a coffee machine.

Disclosure of Invention

The object of the invention is to provide a compact and efficient device for selectively preparing hot and cold milk foam or delivering hot and cold milk, which is distinguished by a lower outlay.

The invention therefore proceeds from a device for preparing cold-hot selectable milk froth or for dispensing cold-hot selectable milk, having a milk container, a milk inlet which connects the milk container via a milk valve line to a cold frothing device which can be activated via an air valve line, a discharge line which is arranged downstream of the frothing device and has a discharge opening, and means for heating the milk froth prepared in the frothing device or the milk flowing through the cold frothing device. The cold frothing device can in particular have a throttle path or throttle through which the milk mixed with air flows for producing the froth. The production of foam can already start downstream of the connection of the milk valve line to the air valve line. A pump, in particular a suction pump, may be provided for conveying milk through the milk inlet, the milk valve line and the cold frothing device.

The outlet opening on the outlet line of the device comprises a steam heating device with a steam generator coupling as a means for optionally heating milk froth prepared in a cold frothing device of the device or milk flowing through the cold frothing device, so that the outlet opening is adapted to heating the milk froth or milk by means of the steam heating device when steam is fed into the steam generator coupling from an external steam generator or the steam outlet line of the steam generator.

The device can prepare cold milk foam or deliver cold milk without connecting the steam generator coupling to an external steam generator. Thus, the apparatus can be used as a simple kit which can be used alone. In order to operate the device as a separate device in the uncoupled state, in which cold milk foam or cold milk can be dispensed by the separate device, the steam generator coupling can be locked, i.e., in particular, it is expedient if the steam generator coupling can be automatically locked, when the steam generator coupling is disconnected or disconnected from the external steam generator or the steam line of the steam generator.

When it is desired to be able to selectively prepare hot milk froth or hot milk, the steam generator coupling is connected to an external steam generator or to a steam discharge line in order to activate the steam heating of the discharge opening, if necessary by supplying steam, and thereby heat the milk froth or milk, which is then discharged from the discharge opening. Since the heating of the milk froth or milk takes place only in the outlet opening, no heat losses occur in the outlet line. In this case, a steam generator is not provided in the device for preparing hot milk froth or hot milk, but rather only a very cost-effective steam generator coupling of the discharge opening of the device is present for coupling to an external steam generator or a steam discharge line of the steam generator having a complementary steam generator coupling.

In other words, the mechanism for preparing hot milk froth or hot milk is independent when the steam generator coupling is coupled directly to the external steam generator or indirectly to the external steam generator outside the device that can be used alone. In order to perform the heating function, the steam generator coupling is no longer latched but opened.

Preferably, the outlet opening or the steam heating device of the outlet opening can be embodied in an uncomplicated manner as a mixer in which the incoming cold milk foam is mixed with the steam supplied by the steam generator coupling and the mixture is thus directly heated.

However, in order to keep the prepared cold milk froth or cold milk as constant as possible in terms of its material composition during heating when it should not come into direct contact with the heated steam, it is also possible, instead of being designed as a mixer, for the steam heating device of the outlet to be designed as a heat exchanger which is heated with externally generated steam and through which the prepared cold milk froth or cold milk flows.

It is particularly advantageous if a separate device for preparing cold-hot, optionally milk froth or delivering cold-hot, optionally milk is connected to the beverage preparation appliance, in particular the coffee beverage preparation appliance, wherein a steam generator coupling of the outlet opening of the device for preparing cold-hot, optionally milk froth or delivering cold-hot, optionally milk can be coupled to a steam outlet line of a steam generator of the beverage preparation appliance, which steam outlet line is provided with a steam valve. When the steam generator coupling is coupled, the steam generator in the beverage preparation appliance can also be used to generate hot milk froth or hot milk if the steam generator is switched on and a steam valve coupled to a steam outlet line on the device is controllably opened.

By supplying the steam generated with the highly efficient external steam generator via the steam generator coupling to the steam heating of the outlet opening of the device for preparing cold-hot optionally milk froth or cold-hot optionally milk, the outlet opening can also be sufficient for heating the milk froth generated from the cold milk or the cold milk which has previously cooled.

In order to generate milk froth from the cooled milk or to discharge the cooled milk, the device comprises a peltier element and a milk container receiving chamber, wherein the milk container receiving chamber and/or a milk container inserted therein is/are connected in a thermally conductive manner to the cold side of the peltier element. The cold side of the peltier element can therefore be arranged on the wall of the milk container receiving space or expediently below the bottom of the milk container receiving space with a flat cold side for uniform cooling.

In order to minimize undesired heating of the milk already in the milk container receiving space or in the milk container received by the milk container receiving space and for hygienic reasons, the milk container receiving space or the milk container preferably has a removable lid having a milk suction line which projects into the milk container or into the milk container receiving space and is provided with a coupling device for the milk suction line. In order to further process the cold or cooled milk, in the device, the milk line leading to the milk valve line is provided with a complementary coupling device, which can be coupled to the coupling device of the milk suction line. In this case, the milk intake line with the coupling device and the complementary coupling device form a milk inlet to the milk line.

In a compact design of the device for preparing cold-hot milk froth or delivering cold-hot milk, the device comprises a housing unit having a milk container receiving space and a peltier element, and a functional unit comprising a cold frothing device, a milk valve circuit and an air valve circuit, wherein the functional unit can be moved in the housing unit substantially horizontally relative to the milk container receiving space or relative to the milk container and the cover in such a way that complementary coupling means of the milk line can be reliably coupled to coupling means of the milk suction line. The functional unit can be moved in a safe manner, in particular manually. In an output position of the functional unit remote from the milk container receiving space or the milk container and the lid, the lid can be easily removed and the milk container can be removed from the milk container receiving space.

In order to precisely guide the movable functional unit and to couple it to the coupling device of the milk intake line, the functional unit is preferably guided in a slide rail of the housing unit.

In a particularly compact embodiment, the multi-way valve, the pump and the electric drive of the multi-way valve and of the pump are arranged in the functional unit. In addition to the multi-way valve outlet, the multi-way valve also comprises a milk valve line, an air valve line and a cleaning fluid valve line, via which the cleaning fluid line can be connected to the multi-way valve outlet. The multi-way valve is designed in particular such that in a first position it connects the multi-way valve outlet to the milk inlet or in a second position it connects the multi-way valve outlet to the milk inlet and to the air inlet on the air supply line, so that air is mixed into the milk by means of the negative pressure generated by the flowing milk or by the action of the pump for generating milk foam. In the third position of the multi-way valve, the multi-way valve outlet of the multi-way valve is connected to the cleaning agent line, so that cleaning agent or cleaning fluid is supplied to the pump, the cold foaming device, the discharge line and the discharge opening, since the pump and the cold foaming device in the functional unit are arranged in a flow-through manner between the multi-way valve outlet and the discharge line.

Furthermore, it is expedient to provide the internal control unit of the electric drive of the pump and of the multiplex valve in the functional unit.

For supplying the functional unit and the peltier element of the device with electrical energy, a supply connection of the power supply device and an activation contact which can be actuated by the movable functional unit, in particular via a push rod, are preferably provided in the housing unit, with which the power supply device can be activated in an operationally safe manner. The drive means can be manually driven via the switching device without an external control device.

In a further embodiment of the internal control unit, it is also possible that the internal control unit has an interface for wireless or wired connection to a central control unit in order to centrally control, in particular with the control unit of the beverage preparation appliance, the drive means of the multi-way valve and of the pump. It is also expedient for the central control unit to control a controllable steam valve in a steam outlet line of a steam generator of the beverage preparation appliance, which steam outlet line can be coupled to a steam generator coupling of a device for preparing optionally cold milk foam or optionally cold milk, or to control the steam generator itself. When the steam generator coupling is coupled and the steam valve is open, the steam generator with the steam outlet line connected thereto is effectively used in a beverage preparation appliance for preparing hot milk froth or hot milk.

The coupling of the steam generator coupling to the steam outlet line of the beverage preparation appliance can also be achieved indirectly via the usual foaming device of the beverage preparation appliance.

Drawings

Embodiments of the invention will be explained in the following on the basis of the drawing comprising two figures, from which the features of the invention can be seen. Wherein, respectively in the form of schematic diagram:

fig. 1 shows a device for preparing cold-hot milk foam or for dispensing cold-hot milk, which is in a state fluidically and controllably decoupled from a beverage preparation device and is prior to operational preparation, and

fig. 2 shows the device according to fig. 1, but in a state in which it is fluidically and controllably connected to a beverage preparation appliance and in operational readiness.

Detailed Description

Fig. 1 shows a device for preparing milk froth, optionally hot and cold, or for dispensing milk, optionally hot and cold, in its entirety designated by 1. The device comprises a housing unit 2 having a milk container receiving space 3 into which a milk container 4 is inserted, and having a removable lid 8 from which a milk suction line 9 extends into the bottom region of the milk container receiving space 3 or into the milk container 4 in the milk container receiving space 3. On one side of the lid 8, the milk suction line 9 is provided with a coupling device 10 accessible from the outside.

Furthermore, the device comprises a functional unit 17 which is horizontally movable in a slide 16 of the housing unit 2. In addition to the milk container receiving space, the functional unit is also arranged in the housing unit 2 and can be moved such that it can be detached or released from the milk container receiving space 3 (as shown in fig. 1) or can be pushed laterally into the milk container receiving space 3 (as shown in fig. 2).

The functional units comprise the multiplex valve 11, the pump 15, the electrical drive means of the multiplex valve 11 and of the pump 15, which are not illustrated, as well as an internal control unit 13 for the multiplex valve 11 and an internal control unit 14 for the pump 15, with which the multiplex valve and the pump can be regulated or switched on. On the side facing the milk container receiving space 3, the functional unit 17 has a complementary coupling device 19 which is suitable for connecting the milk suction line 9 in the milk container 4 or in the milk container receiving space 3 to the milk line 12 in the functional unit in the coupled state of the coupling device 10 (see fig. 2). When the functional unit 17 is moved onto the milk container receiving space 3, milk can be introduced from the milk container 4 or from the milk container receiving space 3 closed by the lid 8 into the milk line 12 of the functional unit via the coupling 10 arranged at the lateral end of the milk suction line 9 and the complementary coupling 19 coupled thereto and can be introduced via the milk line 12 into the milk inlet of the multi-way valve 11.

In particular, for the preparation of cold milk or for the preparation of cold milk foam with the device, the bottom of the milk container receiving chamber 3, not shown, is connected in a thermally conductive manner to the cold side of the peltier element 5. The milk pre-cooled in the refrigerator can be additionally cooled by means of the peltier element 5 in a milk container that can be inserted into the receiving chamber.

For supplying the peltier elements 5, the housing unit 2 has a supply connection 39 which also supplies the internal control unit 13 for the drive means of the multi-way valve 11 and the internal control unit 14 for the drive means of the pump 15. The power supply to the peltier element 5 is effected only in the state in which the functional unit 17 is moved onto the milk container receiving chamber 3 by closing the actuation contact 18 by means of the push rod 18a, see fig. 2.

In addition to the multi-way valve 11 (which is a three-way valve) and the milk line 12 between the complementary coupling device 19 and the milk inlet 20 of the three-way valve, an air line 22, a cleaning agent line 24 and a multi-way valve outlet line 26 are provided in the movable functional unit 17, which leads to the inlet of a pump 15 designed as a suction pump, the outlet of which is connected to an outlet line 29 via a throttle 28. When the milk mixed with air is supplied from the multi-way valve 11 via the pump 15 to the throttle valve 28, the throttle valve has a function for preparing cold milk froth. At the outlet of the throttle 28, a discharge line 29 is connected, which leads to a discharge 27 outside the functional unit 17.

The outlet 27 has a steam generator coupling 37 which is connected to the steam heating of the outlet 27 and which can be coupled to a complementary steam generator coupling 38 which can be acted on by steam via a steam valve 35 of the steam outlet line 34, see fig. 2.

In the configuration of the device according to fig. 1, in which the outlet 27 serves as an outlet for cold milk or cold milk foam, the external steam outlet line is not coupled to the steam generator coupling 37 and the steam generator coupling is blocked.

Whereas, according to fig. 2, when the steam generator coupling 37 is coupled to the complementary steam generator coupling 38, is itself opened and is connected in a steam-conducting manner via the opened steam valve 35 with the steam outlet line 34, the hot steam generated in the steam generator of the beverage preparation appliance 31 can effectively heat up the cold milk froth or the cold milk prepared in the functional unit 17 and flowing into the outlet 27 with the steam heating device, either directly or indirectly. In order to deliver cold milk froth or cold milk from the discharge opening 27, the steam valve 35 is closed.

Expediently, the steam valve 35 in the steam outlet line 34 is controlled by the central control unit 32 of the beverage preparation appliance via a control connection 33, which can be realized by wires or wirelessly and is represented in fig. 2 by dashed lines, with the internal control unit 13 for the multi-way valve 11 and the internal control unit 14 for the pump 15. The internal control units 13, 14 can therefore have an interface via which they communicate with an external central control unit 32 via a control connection 33.

The multi-way valve 11, which is also controllable by the central control unit 32, in the functional unit 17 comprises, in addition to the milk inlet 20, an air inlet 21 with an air line 22 and a cleaning agent inlet 23 with a cleaning agent line 24, which leads to a cleaning agent container, not shown.

In order to operate the device, after the milk container 4 has been inserted into the milk container receiving space 3 and has been closed by the lid 8, the functional unit 17 is moved in the sliding track 16 toward the milk container receiving space 3 onto the milk container lid 8 in such a way that the milk line 12 leading to the multi-way valve 11 is coupled by means of its complementary coupling 19 to the coupling 10 of the milk suction line 9 of the container lid 8 and the starting contact 18 is closed by means of the push rod 18a which is moved onto the milk container receiving space 3.

When the multi-way valve 11 is set in its first position by the internal control unit 13 for it and its drive means, the milk inlet 20 is connected to the multi-way valve outlet 25, wherein the air inlet 21 and the rinsing agent inlet 23 are blocked. The milk sucked by the pump 15 is sucked in from the milk valve path of the multi-way valve outlet 25 and the multi-way valve 11 and is supplied as pure milk to the outlet 27.

When the multi-way valve 11 is adjusted by its drive means into a second position, controlled by the internal control unit 13 for it, the milk inlet 20 is connected to the multi-way valve outlet 25 and the air inlet 21, which is connected to the milk valve line, also called milk flow line, is opened. In addition to the milk sucked in by the pump 15, air is thus sucked in the multi-way valve 11 and this air is mixed with the milk. The milk-air mixture formed is drawn further by the pump 15 through a throttle 28 arranged between the multi-way valve outlet 25 and the discharge 27, which throttle is arranged downstream of the pump 15 in the present embodiment. The milk-air mixture compressed in the throttle valve 28 expands downstream of the throttle valve and milk foam is fed to the discharge 27 via a discharge line 29.

In the third position, which is controlled by the internal control unit 13 and the drive means for the multi-way valve 11, the milk inlet 20 and the air inlet 21 are blocked, while the cleaning agent inlet 23 is opened and the cleaning agent line 24 is connected via the cleaning agent valve line to the multi-way valve outlet 25. In this case, the pump 15 draws cleaning liquid through the multi-way valve 11 and delivers the cleaning liquid through the multi-way valve output line 26, the pump 15 and the discharge line 29 to the discharge 27.

In a variant of the device 1 for preparing milk froth, the valve positions of the multi-way valve 11 and the operation of the pump 15 can also be selected manually, independently of the beverage preparation appliance, by means of the internal control unit 13 for the multi-way valve 11 and the internal control unit 14 for the pump 15 via a circuit diagram, not shown.

As shown in fig. 1, the outlet 27 of the device 1 for preparing cold froth or delivering cold milk does not have to be connected to an external steam outlet line 34 or a steam generator. However, when the steam outlet valve 35 is closed by the central control unit 32 or the steam generator is not activated, the device can also remain connected to the steam outlet line 34 for preparing cold foam or for dispensing cold milk, as shown in fig. 2.

For the preparation of hot milk froth or hot milk, the outlet opening 27 must be functionally coupled via its steam generator coupling 37 to a steam outlet line (e.g. 34) or a steam generator, so that in the present example steam is fed from the steam outlet line 34 via a controlled steam outlet valve 35 into the outlet opening 27.

In fig. 1, it is shown that the outlet 27 of the device 1 can be coupled with its steam generator coupling 37 to a complementary steam generator coupling 38 of the beverage preparation appliance 31 instead of a conventional foamer 30, which comprises a steam generator coupling 36 and a foamer-milk line, not shown, and which can only deliver hot milk foam.

List of reference numerals

Device for preparing milk froth

2 housing unit

3 milk container holding cavity

4 milk container

5 Peltier element

6 Peltier element cold side

Hot side of 7 Peltier element

8 cover

9 milk suction pipeline

10 coupling device

11 multi-way valve

12 milk pipeline

13 internal control unit

14 internal control unit

15 pump

16 sliding rail

17 functional unit

18 make contact

18a push rod

19 complementary coupling device

20 milk inlet

21 air inlet

22 air pipeline

23 cleaning agent inlet

24 cleaning agent pipeline

25 multi-way valve outlet

26 multi-way valve output pipeline

27 discharge port

28 throttle valve

29 discharge line

30 bubbler

31 beverage preparation appliance

32 central control unit

33 control connection device

34 steam discharge line

35 steam valve

36 steam generator coupling

37 steam generator coupling device

38 complementary steam generator coupling

39 power supply connector

Claims (15)

1. A device (1) for preparing milk froth, optionally hot and cold, or for dispensing milk optionally hot and cold, comprising

A milk container (4),

a milk inlet which connects the milk container (4) via a milk valve line with a cold frothing device which can be activated via an air valve line,

a discharge line (29) arranged downstream of the cold foaming device, the discharge line having a discharge opening (27), and

wherein the discharge opening (27) comprises a steam heating device with a lockable steam generator coupling (37), with which the discharge opening (27) is adapted to heat cold milk froth prepared in a cold frothing device or to heat milk flowing out of the cold frothing device,

wherein the device comprises a Peltier element (5) and a milk container receiving chamber (3),

wherein the milk container receiving chamber (3) and/or the milk container (4) is/are connected to the cold side (6) of the Peltier element (5) in a heat-conducting manner, and

wherein the device (1) comprises a housing unit (2) having a milk container receiving chamber (3) and a Peltier element (5), and a functional unit (17) having a milk valve circuit, an air valve circuit and a cold frothing device, and

the functional unit (17) can be displaced in the housing unit (2) substantially horizontally in such a way that a complementary coupling (19) of the milk line can be coupled to the coupling (10) of the milk suction line (9).

2. The apparatus of claim 1,

the device further comprises a selectively activatable mechanism for heating milk froth prepared in the cold frothing apparatus or milk flowing through the cold frothing apparatus.

3. The apparatus according to claim 1 or 2,

the movable functional unit (17) is guided in a slide rail (16) of the housing unit (2).

4. The apparatus of claim 1 or 2,

the Peltier element (5) is arranged below the bottom of the milk container receiving chamber (3).

5. The apparatus according to claim 1 or 2,

the milk container receiving chamber (3) or the milk container (4) has a removable lid (8) which has a milk suction line (9) which projects into the milk container (4) or into the milk container receiving chamber (3) and has a coupling device (10) for the milk suction line (9), and

the milk line (12) leading to the milk valve line is provided with a complementary coupling device (19) which can be coupled to the coupling device (10) of the milk suction line (9), wherein the milk suction line (9) with the coupling device (10) and the complementary coupling device (19) form a milk inlet leading to the milk line (12).

6. The apparatus according to claim 1 or 2,

a multi-way valve (11) is arranged in the functional unit (17), comprising a multi-way valve outlet (25), the milk valve line, the air valve line and a cleaning fluid valve line, via which a cleaning fluid line (24) can be connected to the multi-way valve outlet (25),

in the functional unit (17), a pump (15) and a cold foaming device are arranged between the multiway valve outlet (25) and the discharge line (29), and

the functional unit (17) is provided with an electric drive for the multi-way valve (11) and for the pump (15).

7. The apparatus of claim 6,

an internal control unit (13, 14) for the electric drive of the multi-way valve (11) and of the pump (15) is provided in the functional unit (17).

8. The apparatus of claim 6,

a power supply connection (39) and an activation contact (18) that can be actuated by the movable functional unit (17) are arranged in the housing unit (2), with which activation contact the power supply of the functional unit (17) and of the Peltier element (5) can be activated.

9. The apparatus of claim 7,

the internal control units (13, 14) have an interface for wireless or wired connection to a central control unit (32).

10. The apparatus according to claim 1 or 2,

the steam generator coupling (37) is designed to be automatically lockable in the uncoupled state.

11. The apparatus according to claim 1 or 2,

the outlet (27) has a mixing device as a steam heating device for mixing milk froth or milk prepared in the cold frothing device with steam.

12. The apparatus according to claim 1 or 2,

the discharge port (27) has a heat exchanger heated by steam as a steam heating device.

13. A beverage preparation appliance having a steam generator and having a device (1) for preparing cold-hot selectable milk froth or outputting cold-hot selectable milk according to claim 1, 2 or 10,

it is characterized in that the preparation method is characterized in that,

a steam generator coupling (37) of the device (1) can be coupled to a steam outlet line (34) of the steam generator, which steam outlet line is provided with a controllable steam valve (35).

14. The beverage preparation appliance of claim 13,

a multi-way valve (11) is arranged in the functional unit (17), comprising a multi-way valve outlet (25), the milk valve line, the air valve line and a cleaning fluid valve line, via which a cleaning fluid line (24) can be connected to the multi-way valve outlet (25),

in the functional unit (17), a pump (15) and a cold foaming device are arranged between the multiway valve outlet (25) and the discharge line (29), and

the function unit (17) is provided with an electric drive of the multi-way valve (11) and the pump (15),

an internal control unit (13, 14) for the electric drive of the multi-way valve (11) and of the pump (15) is provided in the functional unit (17),

the internal control units (13, 14) have an interface for wireless or wired connection to a central control unit (32),

the central control unit (32) is an integral part of the beverage preparation appliance (31), and

an actuating device for the steam valve (35) is connected to the central control unit (32).

15. A beverage preparation appliance as claimed in claim 13 or 14,

the beverage preparation appliance is a coffee beverage preparation appliance.