Milk froth/coffee beverage maker

The invention relates to a milk froth/coffee beverage maker according to the introductory clause of Claim 1.

Milk froth/coffee beverages of the cappuccino-type beverages are trendy due to their excellent flavor and their good digestibility. Such milk froth/coffee beverages are made in a generally known manner by so-called cappuccino machines. They comprise an electrically heatable hot water pressure tank. From this hot water pressure tank, hot water can be passed, on the one hand, through a strainer filled with coffee grounds to make coffee/espresso. Moreover, steam can be taken from the hot water pressure tank via a valve-controlled frothing nozzle for frothing milk. To this end, cold milk is poured into a vessel, and the hot steam is passed through the milk, with a relatively stable milk froth being formed. For preparing a milk froth/coffee beverage of the cappuccino type, either hot coffee is filled into a drinking cup and milk froth is subsequently poured over it, or milk froth is first formed in the drinking cup by means of the steam nozzle and subsequently filled up with coffee, with the milk froth floating on the coffee. Cappuccino machines are not only known as large- volume professional machines for cafes and restaurants but also as small appliances for private use.

All these cappuccino machines require a hot water pressure tank which produces - through a supply of high electrical energy - hot water and steam via the frothing nozzle. This high energy is taken from the power supply network so that a permanent electrical cable connection is required. Network-independent, mobile milk froth/coffee beverage making is practically not feasible with the above method due to the high energy consumption.

Moreover, small battery-powered manual whisks are known for the purpose of milk frothing. With it, a cappuccino is made such that milk is poured into a cup and whisked until milk froth has developed. Coffee is subsequently added. Obviously,

however, this mobile type of making cappuccino is directed to the preparation of a few cappuccinos in the private area. For professional mobile use, however, this method of cappuccino making is not suitable because it must be excluded for reasons of hygiene that - in a multitude of different drinking cups for different persons - milk will be, one after the other, frothed with only one manual whisk. Moreover, handling would be time-consuming and awkward.

At social events or in means of transportation, the quality of mobile, tapped coffee beverages or milk/coffee beverages has so far been rather poor - mobile dispensing of savory, easily digestible milk froth/coffee beverages such as cappuccinos is not offered.

It is the object of the invention to provide a milk froth/coffee beverage maker, suitable for professional, mobile dispensing of milk froth/coffee beverages (cappuccinos).

This problem is solved by the characteristics of Claim 1 , as well as the characteristics of Claim 4.

According to Claim 1 , the milk froth/coffee beverage maker is designed independent from an external energy supply and mobile. For this, two refillable and preferably replaceable liquid containers as coffee container and milk container are arranged in a receiving holder, thermally insulated from each other, each having a lower discharge opening in operating position with an allocated container connection, preferably a container connection valve as a quick coupling.

The container connections are connected by tubes with allocated manually operable tapping valves with tap openings.

Milk frothing means are allocated to the milk container, independent of any maker- external energy supply, such that a pressure cartridge replaceably connected to the milk container will introduce nitrous oxide (N ₂ O) as a foaming and expanding agent into the milk container. When operating the allocated tapping valve as a milk froth tapping valve, N ₂ O-enriched milk comes out. The N ₂ O contained in the milk froth is released and evaporates upon leaving the milk froth tapping valve and thus produces the milk froth.

A combination of the above features provides a device for a mobile milk froth/coffee beverage maker which is simple to manufacture and easy to operate. It can be used as a mobile device, for example, during events, or for use in means of transportation, such as trains or airplanes.

For reasons of strength and hygiene, stainless steel containers are expediently used as liquid containers in which the discharge openings and the container connections each are at the lowest point of the container. The arrangement is selected such that tapping, especially from the coffee container, can be done by gravitational force. Since nitrous oxide builds up a certain pressure in the milk container, it is to be designed as a pressure container. Moreover, all tubes, valves and couplings must be made of stainless steel and/or plastic approved under food laws. Opposite the discharge openings, closable filling openings may each be provided.

According to Claim 2, the pressure cartridge is connected - via a screw connection - to an upper area of the milk container in operating position, with a valve or a penetration opening of the pressure cartridge being opened during the screwing action, for a connection with the interior of the milk container. Expediently, the milk container has a volume of approx. 1.5 liter and is filled with approx. 1 liter cold milk maximum so that the connection of the pressure cartridge is located in a gas volume above the level of the milk. The coffee container, however, should have a larger filling volume. Moreover, the milk container can be protected against undue overpressure by providing a rupture disk preferably in a screw mount.

For a concrete design of the milk froth tapping valve, Claim 3 proposes to design it as a disk valve in which the valve disk bears a pin projecting toward the outside in an elastic spout which is open on the end. By supporting and bending the spout in a coffee cup and the pin's excursion connected therewith, the valve disk is shifted from the closed position at the valve seat into a position with an opening gap for the discharge of N ₂ O-enriched milk or milk froth, respectively. With such a milk froth tapping valve, it is easy to make and measure out milk froth. Principally, other valve designs can also be used, e.g. the type of needle valves, it being essential for effective milk froth production that narrow flow-through openings are releasable.

In an alternative embodiment to solve the object of the invention according to Claim 4, the milk froth/coffee beverage maker is also independent from a maker-external energy supply and mobile designed such that two refutable and preferably replaceable liquid containers as coffee container and milk container are arranged in a receiving holder, thermally insulated from each other, which are coupled each, in the operating position, with a lower discharge opening to an allocated container connection valve, preferably a quick coupling of the receiving holder. The container connection valves are connected by tubes with allocated manually operable tapping valves with tap openings. Moreover, milk frothing means are allocated to the milk container, independent of any maker-external energy supply, with an intermediate milk container - being provided in the flow between the milk container connection valve and the downstream milk froth tapping valve - in which a milk froth whisk is arranged controlled by a battery-powered electric motor for producing milk froth in the intermediate milk tank. The intermediate milk tank is preferably designed as a separate container which can be removed for cleaning purposes.

In an advantageous development according to Claim 5, the intermediate milk tank is arranged below the milk container and comprises a float valve at the inlet for dosed, controlled re-supply of milk into the intermediate milk container. As needed, a switch can be operated preferably in the area of the milk froth tapping valve and the milk froth whisk being operated so that milk in the intermediate milk container will be frothed and, due to the centrifugal force of the whisk, can be pushed further into the tapping line to the milk froth tapping valve and out of the downstream tap opening.

In both alternative embodiments above, according to Claim 6, the receiving holder is advantageously formed as an openable, thermally insulated container housing with two compartments partitioned by a thermally insulated wall, one as a warm compartment for the coffee container with hot coffee and one as a cold compartment for the milk container with cold milk, optionally with an intermediate milk container with a milk froth whisk being additionally arranged in the cold compartment. The container housing can especially be manufactured of a foam block of foamed polypropylene, with the filling openings of the liquid containers being located in the area of the top side of the foam block. The tubes on the liquid containers in the warm compartment or the cold compartment as well as the connected valves and couplings will be expediently thermally insulated so that the liquid correspondingly to

be tapped will maintain its preset temperature up to the allocated tapping valve. Basically, the above milk froth/coffee beverage makers can also froth warm milk; however, the frothing result is considerably better with cold milk so that cold milk is to be preferably used from the indicated cold compartment.

According to Claim 7, for a modified embodiment, an additional liquid container is proposed for an additional hot beverage in the warm compartment of the container housing with the same technical connection and tapping methods as for the coffee container. This additional liquid container is preferably provided for hot milk so that simple, traditional milk/coffee beverages can also be made as needed, i.e. without frothed milk, by mixing coffee and hot milk.

In a mobile embodiment according to Claim 8, the container connection valves are self-closing in design and formed with the allocated tapping valves as a structural unit in the type of a valve block. Thus, the tapping valves are located firmly in the area of the receiving holder or the container housing, respectively. Such an embodiment is particularly suitable for fitting it on an undercarriage according to the second alternative of Claim 10, for example for dispensation in the narrow aisles between train compartments.

Alternatively, according to Claim 9, the tapping valves with connected discharge nozzles are arranged in a tapping head, with the tapping valves in the tapping head each being connected - via individual flexible tubes, running jointly in a tube hose, directly or indirectly via a quick-coupling block on the receiving holder or the container housing respectively - with the container connections. This embodiment is particularly suitable for a portable embodiment in the way of a back carrying unit with carrying straps according to the first alternative according to Claim 10. For good handling, the tube hose length should have approximately a length of 90 cm. The carrying straps can be detachably designed. This embodiment with a tapping head and a tube hose can be carried and operated by one person or can otherwise be transported in a mobile fashion, for example via an undercarriage.

In an especially preferred embodiment of a milk froth/coffee beverage maker according to Claim 11 , the back carrying unit features in a lateral view an L-shaped carrying frame, with the shorter L-leg being formed as the bottom base plate and the

longer L-leg as the back plate. The base plate comprises recesses for access to container connections, with the liquid containers being accepted - above the recesses on the base plate - in insulating elements in the type of openable half shells of insulating material. Laterally on the carrying frame, a covering hood swiveling about a vertical axis is provided which, in closed condition, covers the insulating elements with the liquid containers. This relatively large-area covering hood can be used to provide advertising. Moreover, on the top side of the back plate, a tiltable lid plate is arranged.

In a development according to Claim 12, a vertically aligned cup receiving tube which is open toward the bottom is integrated into the back plate as a cup magazine. Thus, a simple space-saving and easy to access cup dispenser can be created in which a plurality of cups can be protected and stored.

Moreover, the base plate - in a top view - should be formed semi-circularly, starting from the back plate, with a corresponding semi-circular arrangement of three liquid containers with adjacent insulating elements. The cup receiving tube is here expediently provided in the front center area of this semi-circular arrangement. This will enable an overall very compact structure with an advantageously small lateral extension. Furthermore, function elements, such as valves, connections, couplings, tube routings, etc. can be taken up in the area of the thickness of the base plate and/or the lid plate. Thus, here too, a compact structure is possible, with the technical parts being covered and not visible from the outside - with good design potentials.

All of the above embodiments of milk froth/coffee beverage makers have in common that they are independent of a maker-external energy supply and can thus be used in mobile applications. If necessary, with small modifications and adjustments of the device, other liquid or nearly liquid mediums - such as creams/cremes, vanilla sauces, etc. - can be optionally tapped as well.

The invention is explained in detail on the basis of a drawing.

It is shown in:

Fig. 1 a diagrammatic perspective representation of a milk froth/coffee beverage maker in a first embodiment;

Fig. 2 a diagrammatic perspective representation of a milk froth/coffee beverage maker in a second embodiment;

Fig. 3 a diagrammatic sectional representation through the milk froth/coffee beverage maker of Fig. 1 , with a milk frothing agent being represented in a first embodiment;

Fig. 4 a diagrammatic sectional representation of a detail enlargement of a tapping head of Fig. 3;

Fig. 5 a diagrammatic sectional representation of a detail enlargement of a tapping valve of Fig. 3;

Fig. 6 a diagrammatic sectional representation through the milk froth/coffee beverage maker of Fig. 1 , with a milk frothing agent being represented in a second embodiment;

Fig. 7 a diagrammatic sectional representation of a detail enlargement of an intermediate milk container of Fig. 6;

Fig. 8 a diagrammatic partial view of a portable milk froth/coffee beverage maker of an additional embodiment;

Fig. 9 a partial view of the milk froth/coffee beverage maker according to Fig. 8 from the bottom in viewing direction A; and

Fig. 10 a representation of the milk froth/coffee beverage maker according to Fig. 8 in a carrying condition.

Fig. 1 and 2 each show diagrammatically in a perspective representation a milk froth/coffee beverage maker 1 in accordance with the invention in two different embodiments. A receiving holder 2 designed as a container housing of the milk

froth/coffee beverage maker 1 is designed - in the embodiment of Fig. 1 - in the type of a back carrying frame with carrying straps 3 so that the milk froth/coffee beverage maker 1 can simply be carried and operated by a person 4 here represented only diagrammatically in a broken line. In the embodiment shown in Fig. 2, the receiving holder 2 is arranged on an undercarriage 5 so that the milk froth/coffee beverage maker 1 can be transported in a mobile fashion with the undercarriage 5. A preferred application for the embodiment of Fig. 1 is, for example, during sports events or the like in stadiums or event arenas; the embodiment of Fig. 2 can be used, for example, preferably in narrow aisles between train compartments. In both embodiments, the milk froth/coffee beverage maker 1 is designed such that it is independent of a maker-external energy supply and can thus be advantageously used in a mobile fashion.

In the following, a concrete structure of such a milk froth/coffee beverage maker 1 is explained in detail in connection with the description of Figures 3 to 7.

Fig. 3 shows a diagrammatic sectional representation through the milk froth/coffee beverage maker 1. The receiving holder 2 is designed as an openable container housing which is partitioned into two compartments with a thermal insulation wall 6. One of the compartments is designed as a warm compartment 7 for a coffee container 8 with hot coffee and the other compartment as a cold compartment 9 for a milk container 10 with cold milk. In the embodiment shown here, an additional liquid container 11 is arranged in the warm compartment 7 for an additional hot beverage, for example, for hot milk.

In the receiving holder 2, the coffee container 8, the milk container 10, as well as the additional liquid container 11 are coupled - in operating setting - to allocated container connection valves 12 of the receiving holder 2. From the individual container connection valves 12, starting from each liquid container 8, 10, 11 , tubes 13 are provided with allocated manually operable tapping valves 14 or, respectively, with tap openings 14'.

For the embodiment of the milk froth/coffee beverage maker 1 represented in Fig. 1 , the tubes 13 are combined in a tube hose 15, with the tube hose length having an approximate length of 90 cm for good handling. Here, the tapping valves 14, 14' can

be arranged with connected discharge nozzles 16 in a tapping head 17. The tube hose 15 in which tubes 13 are combined has been left out in Fig. 3 for reasons of clarity, with tubes 13 being indirectly connected with the container connection valves 12 via a quick-coupling block 18 on the receiving holder 2.

For the embodiment of the milk froth/coffee beverage maker 1 of Fig. 2, the container connection valves 12 are designed self-closing, with the allocated tapping valves 14, 14' forming a structural unit in the type of a valve block 19. In both embodiments, the arrangement of the tapping valves 14, 14' versus the coffee container 8, the milk container 10 and, respectively, the additional liquid container 11 has been chosen such that - with opened tapping valve - the corresponding liquid can flow out from the corresponding container 8, 10, 11 through gravitational force. In the embodiment with a back carrying frame with carrying straps 3, the person 4 carrying the receiving holder 2 can hold in one hand a cup 20 to be filled, while it is possible to operate the tapping valve 14, 14' with the other hand. With the arrangement of the receiving holder 2 on the undercarriage 5, a beverage can be tapped simply and quickly from the selected container 8, 10, 11 by operating the tapping valves 14, 14' on the valve block 19.

For the preparation of a cappuccino with frothed milk, a milk frothing agent is allocated to the milk container 10 in the cold compartment 9 which is independent of a maker-external energy supply. In the embodiment shown in Fig. 3, the milk froth/coffee beverage maker 1 , the milk frothing agent is designed as a pressure cartridge 21 which is replaceably arranged on the milk container 10. The pressure cartridge 21 carries nitrous dioxide (N ₂ O) as a foaming and expanding agent. By operating the allocated tapping valve 14' as a milk froth tapping valve, N ₂ O-enriched milk comes out, with the N ₂ O in the frothing milk being released and evaporating upon leaving the milk froth tapping valve 14' so that milk froth will be produced. Via a screw connection in an upper area of the milk container 10 in operating position, the pressure cartridge 21 can be connected, with a flow connection between the pressure cartridge 21 and the interior of the milk container 10 being provided upon screwing the pressure cartridge 21 to the milk container 10.

Fig. 4 is a diagrammatic sectional representation through the tapping head 17 of Fig. 3. The tubes 13, arranged in the representation left and center in the tapping head

17, are leading to the coffee container 8 and, respectively, the additional liquid container 11 which are both arranged in the warm compartment 7. The allocated tapping valves 14 are here presented only diagrammatically, to be addressed in more detail in connection with the description of Fig. 5. The milk froth tapping valve 14' is designed as a spring-loaded disk valve in which the valve disk 22 bears a pin 23 projecting toward the outside in an elastic spout 24 which is open on the end. If, for example, the milk froth tapping valve 14' is introduced into a cup 20 for tapping milk froth, the spout 24 can rest against the cup wall and bend so that the pin 23 is deflected. Through this deflection of pin 23, the valve disk 22 is moved from its closed position on the valve seat into a position with an opening gap so that milk froth can pass through this opening gap into the cup 20. If the milk froth tapping valve 14' is again removed from the cup wall, the pin 23 also moved again into its closed position so that valve disk 22 is also moved into the closed position again.

Fig. 5 shows a diagrammatic sectional representation through the tapping valve 14 in an exemplary embodiment variant. By operating a key lever 25 (arrow 26), a spring- loaded valve is opened so that liquid can flow through the tapping valve 14 in the direction of an arrow 27. When the key lever 25 is released again, the valve will again close automatically due to the initial tension in the spring so that the flow of liquid is thus stopped.

Fig. 6 shows the milk froth coffee beverage maker 1 in a diagrammatic sectional presentation, and in contrast to the embodiment variant presented in Fig. 3, with an intermediate milk container 28 for making milk froth being allocated in the cold compartment 9 to the milk container 10, instead of the pressure cartridge 21. The intermediate milk container 28 is arranged in the flow route between the milk container 10 and the container connection valve 12 of the milk container 10.

Fig. 7 shows a sectional representation of the intermediate milk container 28 in an enlarged detailed view. Arrows 29 indicate the flow in the intermediate milk container 28 with milk coming from the milk container 10 flowing in the direction of the container connection valve 12. In the intermediate milk container 28, a battery- operated electric motor 30 is provided which drives a milk froth whisk 31 arranged in the milk flow. Moreover, a float valve 32 is provided in the intermediate milk container 28 on the inlet so that a dosed, controlled re-supply of milk into the intermediate milk

container 28 will be possible. The electric motor 30 can be coupled such with the tapping valve 14 allocated to the milk container 10 that, upon operation of the tapping valve 14 or upon operation of a switch, the electric motor 30 will drive the milk froth whisk 31 (arrow 33) so that the milk - flowing through the intermediate milk container 28 by means of the rotation of the milk froth whisk 31 - will be frothed, with the milk froth being pushed further into the direction of the tapping valve 14 and out of the downstream tap opening on the discharge nozzle 16, due to the centrifugal force of the milk froth whisk 31.

Independent of the above described possible embodiment variants for the milk froth/coffee beverage maker 1 , it will always be independent of any maker-external energy supply and thus mobile in design. Moreover, a milk froth/coffee beverage in the fashion of a cappuccino can be made through the milk frothing means designed as pressure cartridge 21 or, respectively, as a milk froth whisk 31 which are also designed independent of a maker-external energy supply. The receiving holder 2 with the two compartments 7 and 9 formed therein is designed such for taking up the individual liquid containers 8, 10 and 11 , respectively, and for the connection of the tapping valves 14 and 14' respectively that an assembly or disassembly of the individual component parts is possible quickly and easily, also providing good cleaning possibilities of the individual component parts.

Fig. 8 shows an additional portable embodiment of a milk froth/coffee beverage maker in its basic structure. A back carrying unit 34 has - in a lateral view - an L- shaped carrying frame 35, with a shorter L-leg as the bottom base plate 36 and a longer L-leg, as the back plate 37 extending therefrom toward the top. The attached carrying straps pointing into the drawing level are not presented here for reasons of clarity. A lid plate 38 tiltable to the top is provided on the top side of the back plate 37.

Starting from the back plate 37, the base plate 36 as well as the lid plate 38 are designed in a semi-circular form. Laterally on the back plate 37, a covering hood 40 swiveling about a vertical axis 39 is provided which has a semi-circular curvature according to the base plate 36 and the lid plate 38 so that the back carrying unit 34 has, overall, a semi-cylindrical form in the closed condition of the covering hood 40.

The base plate 36 has three staggered recesses 41a, 41 b, 41c, above which three bottle-shaped liquid containers 42a, 42b, 42c are arranged allocated in operating condition. The liquid containers 42a, 42b, 42c are each accepted into tubular insulating elements 43a, 43b, 43c which each consist of openable half shells, as shown by means of the insulating element 43a. The insulating elements 43a, 43b, 43c and the liquid containers 42a, 42b, 42c contained therein are each supported above the recesses 41a, 41 b, 41c on the base plate 36. Moreover, they abut each other, as well as the back plate 37 and a central cup receiving tube 44 and - with the closed covering hood 40 - they are kept and fixed overall in the proper position.

Fig. 9 shows an enlarged partial view onto the bottom side of the relatively thick base plate 36, with its recesses 41 a, 41 b, 41 c. Through these recesses 41 a, 41 b, 41 c, lower connections lying above or protruding toward the bottom - advantageously quick-closing valves of liquid containers 42a, 42b, 42c - are accessible for connection of the corresponding tubes to the tapping valves. In shell-shaped and duct-shaped recesses 45, valves and connections can be taken up and run in a covered fashion, in particular to a tube hose 46.

Fig. 9 shows the lower open part of the cup receiving tube 44 - integrated into the back plate 37 - from which a cup 47 protrudes. By pulling on cup 47, it can be removed from the cup receiving tube as a cup dispenser, with the next cup arriving in the corresponding standby position.

Fig. 10 shows a person 48 carrying on his/her back a milk froth/coffee beverage maker 1 in the embodiment according to Fig. 8. This shows clearly the compact structure and ergonomic handling.