BEVERAGE MAKER AND METHOD FOR OPERATING A BEVERAGE MAKER

Description

[0001] A beverage maker is provided which contains a control unit which is configured to carry out at least the following steps in a cleaning program of the beverage maker: ensuring that there is steam pressure in the steam generator and / or in the hot water generator and that at least one steam metering valve is closed, stopping a supply of electrical energy to the steam generator and / or to the hot water generator, opening the at least one steam metering valve when the control unit is signaled that the beverage outlet has a fluidic connection to a cleaning liquid, and allowing the cleaning liquid to take effect. The beverage maker has the advantages that cleaning or descaling of the beverage maker is simpler, faster, less prone to errors, and requires less energy (i.e., more economical). Furthermore, a corresponding method for cleaning a beverage maker is presented.

[0002] When it comes to coffee beverages, coffee-milk blends such as cappuccino or latte macchiato are becoming increasingly popular. Coffee machines, both fully automatic and semi-automatic, are therefore generally equipped with features for dispensing hot milk foam or milk with the coffee. Since milk is a liquid and perishable food, daily cleaning is generally required to maintain hygiene standards and prevent buildup. The steam generators used for frothing, such as steam boilers or instantaneous water heaters, can become calcified very quickly due to their high temperatures, depending on the water quality and the quantity of milk beverages dispensed. Consequently, regular descaling with appropriate descaling agents is required by the user.

[0003] Typically, to clean or descale such a beverage maker, a storage container for milk or water is removed from the beverage maker and replaced with a container containing cleaning fluid or descaler. After starting a cleaning or descaling program, the cleaning fluid is actively pumped (i.e., using electrical energy) via a Venturi effect or the action of a feed pump into the beverage maker via a feed line, allowing the components of the beverage maker to be cleaned. The user must then exchange the container containing cleaning fluid for a container containing fresh water so that the beverage maker can be rinsed with fresh water in a further step of the cleaning program to prevent any cleaning fluid residues from remaining in the beverage maker. For beverage makers with a fixed water connection, the cleaning fluid is supplied (e.g.a descaler) via the water supply line.

[0004] This approach is disadvantageous because it requires a large amount of equipment. Furthermore, it requires complex and time-consuming interaction by the user or service technician. Furthermore, it involves numerous error-prone work steps. Furthermore, the need to actively transport cleaning fluid through the fluid lines via a Venturi effect or a feed pump requires a certain amount of electrical energy, which could fundamentally be saved to make the cleaning process less energy-intensive.

[0005] EP 3 064 104 A1 discloses methods and devices for preparing and dispensing cold and hot milk, which comprise an automatic washing of channels of the device after a milk dispensing step.

[0006] Based on this, the object of the present invention was to provide a beverage maker and a method for operating a beverage maker that do not have the disadvantages of the prior art. In particular, the beverage maker and the method should make it possible to simplify cleaning (e.g., descaling) of components of a beverage maker, making it faster, less error-prone, and less energy-intensive (i.e., more economical).

[0007] The object is achieved by the beverage maker having the features of claim 1 and the method having the features of claim 8. The dependent claims show advantageous embodiments.

[0008] According to the invention, a beverage maker is provided, comprising a cold water connection; a pump for conveying water in the beverage maker; a hot water generator; a brewing unit; at least one brewing valve arranged downstream of the hot water generator and upstream of the brewing unit; a steam generator; a beverage outlet; at least one steam metering valve arranged upstream of the beverage outlet; and a control unit; wherein the hot water generator and the at least one steam metering valve are fluidically connected, characterized in that the control unit is configured to carry out at least the following steps in a cleaning program of the beverage maker: a) ensuring that steam pressure is present in the steam generator and / or the hot water generator and the at least one steam metering valve is closed; b) stopping a supply of electrical energy to the steam generator and / or the hot water generator;c) opening the at least one steam dosing valve when the control unit is signaled that the beverage outlet of the beverage maker has a fluidic connection to a cleaning liquid; d) allowing the cleaning liquid to act, wherein the hot water generator is i) arranged fluidically parallel to the steam generator; or ii) arranged fluidically in series with the steam generator and upstream of the steam generator in the direction of the pump and the cold water source.

[0009] According to the invention, the term "cleaning" also includes the term "descaling," meaning that the term "cleaning fluid" also includes the term "descaling fluid." The terms "upstream" and "downstream" do not refer to a fluid flow during the cleaning operation of the beverage maker, but rather to a fluid flow during the preparation operation of the beverage maker, meaning a fluid flow from the cold water connection toward the beverage outlet.

[0010] It is possible for the control unit to be configured to open the at least one steam dosing valve immediately upon receiving the signal that the beverage outlet and / or a steam pipe of the beverage maker has a fluidic connection to a cleaning fluid, or to allow a certain time (cooling time) to elapse after receiving this signal before the additional steam dosing valve is opened. In the first case, the cleaning fluid can be drawn in slowly via a continuously increasing negative pressure. In the second case, the cleaning fluid can be drawn in quickly via an already existing negative pressure, which can be advantageous with regard to the cleaning agent flow, particularly in long fluid lines.

[0011] The hot water generator and / or steam generator can be designed as a continuous-flow heater. Alternatively, the hot water generator and / or steam generator can be designed as a boiler.

[0012] Ensuring that steam pressure is present in the steam generator and / or the hot water generator can be achieved by causing the control unit to supply the steam generator and / or the hot water generator with such a high amount of electrical energy that steam is generated in the steam generator and / or the hot water generator. In particular, the at least one steam metering valve is not a check valve.

[0013] The signaling of the control unit that the beverage outlet has a fluidic connection to a cleaning liquid can be done either manually by a user (e.g. via an input unit of the beverage maker connected to the control unit, for example a touch screen of the beverage maker) or automatically by the beverage maker (e.g. via a sensor for detecting cleaning liquid, which is located at the outlet of the beverage outlet or at the outlet of the steam pipe and is communicatively connected to the control unit).

[0014] The beverage maker has the decisive advantages that it can be cleaned easier, faster, is less prone to errors and requires less energy (i.e. more economical). The reason for this is, on the one hand, that the negative pressure generated in the steam generator and / or in the hot water generator is used to suck a cleaning liquid into the beverage maker. Thus, no electrical energy is required to transport the cleaning liquid into the beverage maker (especially to the steam generator and / or hot water generator) through the action of the beverage maker's pump. In this respect, the beverage maker according to the invention saves electrical energy because the steam generator already has a steam pressure during normal operation and the hot water generator (especially in the design as a continuous flow heater) only needs to be heated by a minimal amount of energy in order to also generate steam pressure in the hot water generator.Furthermore, cleaning is faster and less labor-intensive because there is no longer any need to replace a fresh water tank with a tank containing cleaning fluid or to enclose a fresh water inlet with a cleaning fluid inlet.

[0015] Since typical milk cleaners are acidic (i.e. the cleaning fluids have an acidic pH value) to ensure effective milk cleaning, it is possible to descale beverage makers with an instantaneous water heater as a steam generator and / or hot water generator during the daily cleaning process. Depending on the prevailing water hardness, cyclical descaling (e.g. annually) may therefore be unnecessary or may be necessary much later. For beverage makers in which the hot water generator and / or steam generator is designed as a boiler, daily descaling with cleaning fluid is disadvantageous. In this case, it makes sense to carry out cyclical descaling at longer intervals (e.g. weekly, monthly or at intervals of several months). Depending on requirements, the control unit can thus be configured to (automatically) initiate a daily, weekly or monthly execution of the cleaning program.Of course, the cleaning program can also be carried out manually by a user at any time, for example by selecting the execution of the cleaning program on an input unit of the beverage maker (e.g. on a touch screen of the beverage maker).

[0016] In particular, the control unit is configured to switch the pump off or to leave it off during steps a) to d). Advantageously, the pump of the beverage maker is a pump that, when switched off, functions as a closed valve, i.e., the negative pressure in the steam generator prevents liquid (water) from being drawn from the cold water connection via the pump. Preferably, the pump has an integrated check valve. In particular, the pump is selected from the group consisting of oscillating armature pumps, vane pumps, and gear pumps with an integrated check valve.

[0017] Particularly preferably, the control unit is configured to switch on the pump after step d) and to pump water until there is no more cleaning fluid in the beverage maker. This ensures that no cleaning fluid residues enter a beverage provided by the beverage maker after the cleaning program has been executed.

[0018] The beverage maker is optionally characterized in that it contains a steam pipe and at least one additional steam metering valve upstream of the steam pipe, wherein the control unit is configured to open the at least one additional steam metering valve in the cleaning program of the beverage maker when the control unit is signaled that the steam pipe has a fluidic connection to a cleaning liquid. It is possible for the control unit to be configured to open the at least one additional steam metering valve immediately after receiving this signal, or to allow a certain time (cooling time) to elapse after receiving this signal until the additional steam metering valve is opened.This design of the beverage maker with a steam pipe has the advantage that the steam pipe can also be cleaned, and the steam pipe, in addition to the beverage outlet, can be used as an inlet for the cleaning fluid to clean the hot water generator and / or steam generator. The at least one additional steam metering valve is, in particular, not a check valve.

[0019] The beverage maker can further be characterized in that the control unit is configured to close the brewing valve during the cleaning program. This has the advantage that no cleaning fluid can enter the brewer during the cleaning program.

[0020] Furthermore, the beverage maker can be characterized in that a steam feed valve is arranged upstream of the steam generator, wherein the control unit is preferably configured to close or open the steam feed valve during the cleaning program. Closing the steam feed valve has the advantage that no cleaning fluid can pass through the steam feed valve and reach the hot water generator. This reduces the amount of cleaning fluid used to clean the steam generator. Opening the steam feed valve has the advantage that cleaning fluid can pass through the steam feed valve and reach the hot water generator, thus also allowing the hot water generator to be cleaned.

[0021] In a first alternative according to the invention, the hot water generator of the beverage maker is arranged fluidically parallel to the steam generator, wherein a fluid line is then preferably arranged downstream of the hot water generator, which fluid line is fluidly connected via a bypass valve (a bypass line) to a fluid line arranged downstream of the steam generator, wherein the control unit is particularly preferably configured to close or open the bypass valve during the cleaning program. Opening the bypass valve has the advantage that cleaning fluid can also be sucked into the hot water generator, and thus the hot water generator can also be cleaned. Closing the bypass valve has the advantage that no cleaning fluid can enter the hot water generator, whereby the consumption of cleaning fluid is lower if only cleaning of the steam generator is desired.It is conceivable that the hot water generator of the beverage maker is arranged fluidically parallel to the steam generator and that the beverage maker does not have such a bypass line and bypass valve (cost-effective design), whereby cleaning of the steam generator and the hot water generator is also possible in this case.

[0022] In a second alternative according to the invention, the hot water generator is arranged fluidically in series with the steam generator and upstream of the steam generator in the direction of the pump and the cold water source, wherein the control unit is preferably configured to open or close a steam feed valve of the beverage maker (arranged upstream of the steam generator) during the cleaning program. Opening the steam feed valve has the advantage that cleaning fluid can be drawn through the steam generator into the hot water generator. Closing the steam feed valve has the advantage that no cleaning fluid can penetrate to the hot water generator if only cleaning of the steam generator is desired. This allows cleaning fluid to be saved.

[0023] The beverage maker can be characterized in that a pump is arranged in a fluid line upstream of the beverage outlet, which pump is suitable for supplying air into the fluid line. This has the advantage that the steam generated in the steam generator (e.g., during normal operation of the beverage maker) can be enriched with air before it exits the beverage outlet. The air is required to produce milk foam. This pump, in particular, has an integrated check valve.

[0024] According to the invention, a method for cleaning a beverage maker is further presented, wherein the method comprises at least the following steps: a) Ensuring that steam pressure is present in a steam generator and / or in a hot water generator of the beverage maker and that at least one steam metering valve of the beverage maker, which is arranged upstream of a beverage outlet of the beverage maker, is closed; b) Stopping a supply of electrical energy to the steam generator and / or to the hot water generator; c) Opening the at least one steam metering valve when a control unit of the beverage maker is signaled that the beverage outlet of the beverage maker has a fluidic connection to a cleaning liquid; and d) Allowing the cleaning liquid to take effect, wherein the hot water generator and the at least one steam metering valve are fluidically connected, and wherein the hot water generator is i) arranged fluidically parallel to the steam generator; or ii) arranged fluidically in series with the steam generator and upstream of the steam generator in the direction of the pump and the cold water source.

[0025] It is possible that the at least one steam dosing valve is opened immediately after receiving the signal that the beverage outlet and / or a steam pipe of the beverage maker has a fluidic connection to a cleaning liquid, or after receiving this signal, a certain time (cooling time) is allowed to elapse before the further steam dosing valve is opened.

[0026] In particular, the at least one steam metering valve is not a check valve.

[0027] The method according to the invention allows for simpler, faster, less error-prone and less energy-consuming (i.e. more economical) cleaning or descaling of the beverage maker.

[0028] In particular, the pump is switched off during steps a) to d) of the method. In a preferred embodiment of the method, the pump is switched on after step d) and continues to pump water until there is no more cleaning fluid in the beverage maker.

[0029] The method is preferably characterized in that the beverage maker includes a steam pipe and at least one further steam metering valve upstream of the steam pipe, wherein in the method the at least one further steam metering valve is opened when the control unit of the beverage maker is signaled that the steam pipe has a fluidic connection to a cleaning liquid. It is possible for the at least one further steam metering valve to be opened immediately after receiving this signal, or for a certain time (cooling time) to elapse after receiving this signal before the further steam metering valve is opened. In particular, the at least one further steam metering valve is not a check valve.

[0030] Furthermore, the method can be characterized in that the beverage maker has a brewing valve arranged downstream of the hot water generator and upstream of a brewing unit of the beverage maker, wherein the brewing valve is closed in the method.

[0031] In addition, the method can be characterized in that a steam feed valve is arranged in the beverage maker upstream of the steam generator, wherein the steam feed valve is closed or opened in the method.

[0032] In a first alternative according to the invention, the method is characterized in that the hot water generator of the beverage maker is arranged fluidically parallel to the steam generator, wherein a fluid line is preferably arranged downstream of the hot water generator, which fluid line is fluidly connected via a bypass valve (a bypass line) to a fluid line arranged downstream of the steam generator, wherein the bypass valve is particularly preferably closed or opened in the method. It is conceivable that the hot water generator of the beverage maker is arranged fluidically parallel to the steam generator and that the beverage maker does not have such a bypass line or bypass valve (cost-effective design).

[0033] In a second alternative according to the invention, the method is characterized in that the hot water generator of the beverage maker is arranged fluidically in series with the steam generator and upstream of the steam generator in the direction of the pump and the cold water source, wherein in the method a steam feed valve of the beverage maker is particularly preferably opened or closed.

[0034] Furthermore, the method can be characterized in that a pump of the beverage maker is arranged in a fluid line of the beverage maker upstream of the beverage outlet, which pump (e.g., during normal operation of the beverage maker) supplies air to the fluid line. The air is required to generate milk foam. This pump, in particular, has an integrated check valve.

[0035] In a preferred embodiment, the method according to the invention is applied to a beverage maker according to the invention.

[0036] The subject matter of the invention will be explained in more detail with reference to the following figures and examples, without wishing to restrict it to the specific embodiments shown here.

[0037] Figure 1shows a schematic diagram of the structure of a beverage maker according to the invention in an embodiment in which the hot water generator 3 and the steam generator 5 are fluidically connected in parallel. The direction of the arrows in the fluid lines indicates the flow direction of the cleaning fluid during cleaning operation. Here, the steam pipe 8 and / or the beverage outlet 7 (or its outlets) are fluidically connected to a container 15 containing cleaning fluid. To start the cleaning program, the steam metering valve 9 and the further steam metering valve 10 are opened by the control unit either automatically (by detecting a fluidic connection to the cleaning fluid) or manually (by user input, for example via a touchscreen of the beverage maker), either immediately after a fluidic connection to a cleaning fluid has been established or only after a certain time has elapsed (cooling time).Due to the opening of the steam metering valve 9 and the additional steam metering valve 10, cleaning fluid is drawn into the steam generator 5 by the negative pressure in the steam generator 5, where it can exert its cleaning effect (e.g., descaling effect). In this embodiment, the control unit causes the bypass valve 12 to be closed and, if necessary, the steam feed valve to be closed, so that no cleaning fluid can enter the hot water generator 3. Such a valve circuit has the advantage that only the steam generator 5 is cleaned, thus requiring a smaller amount of cleaning fluid.

[0038] Figure 2 shows schematically the structure of a beverage maker according to the invention in an embodiment as in Figure 1, only with the difference that the control unit causes the bypass valve 12 to open or keep open so that cleaning liquid can be drawn into the hot water generator 3 if it has previously been placed under steam pressure, whereby the control unit opens the steam dosing valve 9 and the further steam dosing valve 10 either immediately after a fluidic connection with a cleaning liquid has been established or only after a certain time has elapsed (cooling time). Such a switching of the valves has the advantage that the hot water generator 3 can be cleaned. If the steam generator 5 was not previously under steam pressure, i.e. is under ambient pressure or has already been cleaned or descaled in a first step, only the hot water generator 3 is cleaned.

[0039] Figure 3 shows schematically the structure of a beverage maker according to the invention in an embodiment as in Figure 1, with the only difference being that the control unit causes the steam feed valve 11 to open or keep it open and the bypass valve 12 to close or keep it closed, so that cleaning fluid is drawn into the steam generator 5 and the hot water generator. Such a valve circuit has the advantage that not only the hot water generator 3 and the steam generator 5 can be cleaned, but also a section of fluid line located upstream of the hot water generator 3 and the steam generator 5.

[0040] Figure 4shows a schematic diagram of the structure of a beverage maker according to the invention in an embodiment in which the hot water generator 3 and the steam generator 5 are fluidically connected in series. To start the cleaning program, the steam dosing valve 9 and the further steam dosing valve 10 are opened by the control unit either automatically (by detecting a fluidic connection to the cleaning liquid) or manually (by user input, e.g., via a touch screen of the beverage maker). Due to the opening of the steam dosing valve 9 and the further steam dosing valve 10, cleaning liquid is drawn into the steam generator 5 by the negative pressure in the steam generator 5, where it can exert its cleaning effect (e.g., descaling effect). In this embodiment, the control unit can, if necessary, cause the steam feed valve 11 to be closed, so that no cleaning liquid can enter the hot water generator 3.Such a valve circuit has the advantage that only the steam generator 5 is cleaned, which means that a smaller amount of cleaning fluid is required.

[0041] Figure 5 shows schematically the structure of a beverage maker according to the invention in an embodiment as in Figure 4 , with the only difference that the control unit causes the steam feed valve 11 to open or keep it open, so that cleaning fluid is drawn into the hot water generator 3 if it has previously been pressurized with steam. The control unit opens the steam metering valve 9 and the additional steam metering valve 10 either immediately after a fluid connection with a cleaning fluid has been established or only after a certain time (cooling time) has elapsed. Such a valve switching has the advantage that both the hot water generator 3 and the steam generator 5 are cleaned. Example 1 - Steam generation in a parallel steam generator

[0042] The following procedure refers to a Figure 1 illustrated beverage maker according to the invention. Step Proceed 1. Provide chemical(s) The container(s) 15 with cleaning fluid (e.g. descaling agent) is / are placed underneath. 2. Generate steam The steam generator 5 generates steam, which exits the steam pipe 8 and / or the beverage outlet 7 and flows into the vessel(s) 15, with the brewing valve 6 and the bypass valve 12 closed. 3. Prepare the piping system for vacuum Steam generator 5 is shut down. Steam feed valve 11 is closed, if necessary, so that no water can flow into steam generator 5. Steam metering valve 9 and the additional steam metering valve 10 remain open. 4. Vacuum up chemicals The steam in the piping system cools and condenses. This creates a vacuum in the piping system. The liquid from the vessel(s) 15 is sucked in and flows into the steam generator 5. 5. Effective phase Allow the chemical(s) in the cleaning fluid to work to dissolve residues. 6. System Flushing The container(s) 15 is / are removed. The steam generator 5, the piping system, the steam metering valve 9, the additional steam metering valve 10, the steam pipe 8, and the beverage outlet 7 are rinsed with cold and / or hot water via the pump 2. Additionally, the line section from the hot water generator 3 to the brewing unit 6 can be rinsed to remove any residues of the cleaning fluid.

[0043] If only a single container 15 containing cleaning fluid is placed underneath, the other path in the process is ignored, and either valve 9 or valve 10 is closed. The other path is then rinsed with water only. Example 2 - Steam generation in a parallel hot water generator

[0044] The following procedure refers to a Figure 2 illustrated beverage maker according to the invention. Step Proceed 1. Chemical(s) The vessel(s) 15 with cleaning fluid (e.g. provide Descaling agent) is / are stored. 2. Generate steam Steam is generated by the hot water generator 3. The bypass valve 12, steam metering valve 9, and / or other steam metering valves 10 are open. Steam exits the steam pipe 8 and / or the beverage outlet 7 and flows into the vessel(s) 15, while the brewing valve 6 and the steam feed valve 11 are closed. 3. Prepare the piping system for vacuum The hot water generator 3 is shut down. The steam feed valve 11 and the brewing valve 6 are closed. The bypass valve 12, steam metering valve 9, and / or the additional steam metering valve 10 remain open. 4. Vacuum up chemical(s) The steam in the piping system cools and condenses. This creates a vacuum in the piping system. The liquid from the vessel(s) 15 is sucked in and flows into the hot water generator 3. 5. Effective phase Allow the chemical(s) to work to dissolve residues. 6. System Flushing The container(s) 15 is / are removed. The hot water generator 3, the piping system, the steam metering valve 9, the additional steam metering valve 10, the steam pipe 8, and the beverage outlet 7 are rinsed with cold and / or hot water via the pump 2. Additionally, by opening the steam feed valve 11, the line section from the steam generator 5 to the brewing unit 6 can be rinsed to remove any possible residues of the cleaning fluid.

[0045] If only a single container 15 containing cleaning fluid is placed underneath, the other path in the process is ignored, and either valve 9 or valve 10 is closed. The other path is then rinsed with water only. Example 3 - Steam generation in parallel steam generator and hot water generator

[0046] The following procedure refers to a Figure 3 illustrated beverage maker according to the invention. Step Proceed 1. Provide chemical(s) The container(s) 15 with cleaning fluid (e.g. descaling agent) is / are placed underneath. 2. Generate steam Steam is generated by the hot water generator 3 and steam generator 5. The steam feed valve 11, the steam metering valve 9, and / or the additional steam metering valve 10 are open. Steam exits the steam pipe 8 and / or the beverage outlet 7 and flows into the vessel(s) 15, while the brewing valve 6 is closed. 3. Prepare the piping system for vacuum The hot water generator 3 and the steam generator 5 are shut down. The brewing valve 6 and the bypass valve are closed. The steam feed valve 11, steam metering valve 9, and / or other steam metering valves 10 remain open. 4. Vacuum up chemical(s) The steam in the piping system cools and condenses. This creates a vacuum in the piping system. The liquid from the vessel(s) 15 is sucked in and flows into the hot water generator 3 and the steam generator 5. 5. Effective phase Allow the chemical(s) to work to dissolve residues. 6. System Flushing The container(s) 15 is / are removed. Pump 2 rinses the hot water generator 3 and steam generator 5, the piping system, the steam metering valve 9, the additional steam metering valve 10, the steam pipe 8, and the beverage outlet 7 with cold and / or hot water. The bypass valve 12 is open during this process. The brewing valve 6 is closed.

[0047] If only a single container 15 containing cleaning fluid is placed underneath, the other path in the process is ignored, and either valve 9 or valve 10 is closed. The other path is then rinsed with water only. Example 4 - Steam generation in a serially arranged steam generator

[0048] The following procedure refers to a Figure 4illustrated beverage maker according to the invention. Step Proceed 1. Provide chemical(s) The container(s) 15 with cleaning fluid (e.g. descaling agent) is / are placed underneath. 2. Generate steam The steam generator 5 generates steam, which exits the steam pipe 8 and / or the beverage outlet 7 and flows into the vessel(s) 15, with the brewing valve 6 closed. 3. Prepare the piping system for vacuum The steam generator 5 is shut down. The steam feed valve 11 is closed, if necessary, so that no water can flow into the steam generator 5. The steam metering valve 9 and / or the additional steam metering valve 10 remain open. 4. Vacuum up chemical(s) The steam in the piping system cools and condenses. This creates a vacuum in the piping system. The liquid from the vessel(s) 15 is sucked in and flows into the steam generator 5. 5. Effective phase Allow the chemical(s) to work to dissolve residues. 6. System Flushing The vessel(s) 15 are / are removed. The steam generator 5, the piping system, the steam metering valve 9, the additional steam metering valve 10, the steam pipe 8, and the beverage outlet 7 are rinsed with cold and / or hot water via the pump 2.

[0049] If only a single container 15 containing cleaning fluid is placed underneath, the other path in the process is ignored, and either valve 9 or valve 10 is closed. The other path is then rinsed with water only. Example 5 - Steam generation in a serially arranged steam generator and hot water generator

[0050] The following procedure refers to a Figure 5 illustrated beverage maker according to the invention. Step Proceed 1. Provide chemical(s) The container(s) 15 with cleaning fluid (e.g. descaling agent) is / are placed underneath. 2. Generate steam Steam is generated by the hot water generator 3 and the steam generator 5. The steam feed valve 11, the steam metering valve 9, and / or the additional steam metering valve 10 are open. Steam exits the steam pipe 8 and / or the beverage outlet 7 and flows into the vessel(s) 15. The brewing valve 6 is closed. 3. Prepare the piping system for vacuum The hot water generator 3 and the steam generator 5 are switched off. The brewing valve 6 is closed. The steam feed valve 11, the steam metering valve 9, and / or the additional steam metering valve 10 remain open. 4. Vacuum up chemical(s) The steam in the piping system cools and condenses. This creates a vacuum in the piping system. The liquid from the vessel(s) 15 is drawn in and flows into the steam generator 5 and the hot water generator 3. 5. Effective phase Allow the chemical(s) to work to dissolve residues. 6. System Flushing The container(s) 15 are removed. Pump 2 rinses the hot water generator 3 and steam generator 5, the piping system, the steam metering valve 9, the additional steam metering valve 10, the steam pipe 8, and the beverage outlet 7 with cold and / or hot water. The brewing valve 6 is closed.

[0051] Steam generation can also occur sequentially, e.g., first in steam generator 5 and then in hot water generator 3. In the first step, steam generator 5 is heated and filled with cleaning fluid (e.g., descaling agent) via the vacuum. In the second step, only the hot water generator is heated (steam is generated) and the entire line section is filled with cleaning fluid (e.g., descaling agent).

[0052] In an alternative procedure, steam is produced only in hot water generator 3 and steam generator 5 is switched off.

[0053] If only a single container 15 containing cleaning fluid is placed underneath, the other path in the process is ignored, and either valve 9 or valve 10 is closed. The other path is then rinsed with water only. Example 6 - Time interval of cleaning programs

[0054] If the steam generator and hot water generator are designed as instantaneous water heaters, they can be cleaned during the daily cleaning of the beverage maker. Since the hot water generator is less sensitive to limescale, it can alternatively be cleaned at longer intervals (e.g., only weekly).

[0055] If the steam generator and hot water generator are designed as a boiler system, they can be cleaned during a weekly, monthly or at intervals of several months.

[0056] In both cases, the method according to the invention for cleaning a beverage maker is particularly advantageous when the cold water connection is not a cold water tank, but a fixed water connection. This is because the cleaning method according to the invention does not require the laborious removal of the fixed water connection, which usually requires a trained service technician. In this respect, the method according to the invention is significantly simpler and faster and can even be performed by untrained operators. List of reference symbols

[0057] 1:Cold water connection; 2:Pump for transporting liquid in the beverage maker; 3:Hot water generator; 4:Brewing unit; 5:Steam generator; 6:Brewing valve; 7:Beverage outlet; 8:Steam pipe; 9:Steam metering valve located downstream of the steam generator; 10:Additional steam metering valve; 11:Steam feed valve; 12:Bypass valve; 13:Pump for supplying air; 14:Air connection; 15:Container with cleaning fluid.

Claims

1. A beverage maker, comprising a cold water connection point (1); a pump (2) for conveying water into the beverage maker; a hot water generator (3); a brewing unit (4); at least one brewing valve (6), which is arranged downstream of the hot water generator (3) and upstream of the brewing unit (4); a steam generator (5); a beverage outlet (7); at least one steam dosing valve (10), which is arranged upstream of the beverage outlet (7); and a control unit; wherein the hot water generator (3) and the at least one steam dosing valve (10) are fluidically connected, characterized in that the control unit is configured to carry out at least the following steps in a cleaning program of the beverage maker: a) ensuring that a steam pressure is present in the steam generator (5) and / or in the hot water generator (3), and that the at least one steam dosing valve (10) is closed; b) stopping a supply of electrical energy to the steam generator (5) and / or to the hot water generator (3); c) opening the at least one steam dosing valve (10) when it is signaled to the control unit that the beverage outlet (7) of the beverage maker has a fluidic connection to a cleaning liquid; and d) leaving the cleaning liquid to take effect; wherein the hot water generator (3) i. is arranged fluidically parallel to the steam generator (5); or ii. in the direction of the pump (2) and the cold water source, is arranged fluidically in series with the steam generator (5) and upstream of the steam generator (5).

2. The beverage maker according to claim 1, characterized in that the control unit is configured to switch on the pump (2) after step d) and to convey water from the pump (2) until there is no longer any cleaning liquid in the beverage maker.

3. The beverage maker according to one of claims 1 and 2, characterized in that the beverage maker comprises a steam pipe (8) and at least one further steam dosing valve (9) upstream of the steam pipe (8), wherein the control unit is configured to open the at least one further steam dosing valve (9) in the cleaning program of the beverage maker when it is signaled to the control unit that the steam pipe (8) has a fluidic connection to a cleaning liquid.

4. The beverage maker according to any one of the preceding claims, characterized in that the control unit is configured to close the brewing valve (6) in the cleaning program.

5. The beverage maker according to the preceding claim, characterized in that a steam feed valve (11) is arranged upstream of the steam generator (5), wherein the control unit is preferably configured to close or to open the steam feed valve (11) in the cleaning program.

6. The beverage maker according to any one of the preceding claims, characterized in that the hot water generator (3) is arranged fluidically parallel to the steam generator (5), and a fluid line is arranged downstream of the hot water generator (3), said fluid line being fluidically connected via a bypass valve (12) to a fluid line that is arranged downstream of the steam generator (5), wherein the control unit is particularly preferably configured to close or to open the bypass valve (12) in the cleaning program.

7. The beverage maker according to claim 5, characterized in that the hot water generator (3), in the direction of the pump (2) and the cold water source, is arranged fluidically in series with the steam generator (5) and upstream of the steam generator (5), and the control unit is configured to open or to close a steam feed valve (11) of the beverage maker in the cleaning program.

8. A method for cleaning a beverage maker, wherein the method comprises at least the following steps: a) ensuring that a steam pressure is present in a steam generator (5) and / or in a hot water generator (3) of the beverage maker, and that at least one steam dosing valve (10) of the beverage maker, which is arranged upstream of a beverage outlet (7) of the beverage maker, is closed; b) stopping a supply of electrical energy to the steam generator (5) and / or to the hot water generator (3); c) opening the at least one steam dosing valve (10) when it is signaled to a control unit of the beverage maker that the beverage outlet (7) of the beverage maker has a fluidic connection to a cleaning liquid; and d) leaving the cleaning liquid to take effect; wherein the hot water generator (3) and the at least one steam dosing valve (10) are fluidically connected; and wherein the hot water generator (3) i. is arranged fluidically parallel to the steam generator (5); or ii. in the direction of the pump (2) and the cold water source, is arranged fluidically in series with the steam generator (5) and upstream of the steam generator (5).

9. The method according to claim 8, characterized in that the beverage maker comprises a steam pipe (8) and at least one further steam dosing valve (9) upstream of the steam pipe (8), wherein, in the method, the at least one further steam dosing valve (9) is opened when it is signaled to the control unit of the beverage maker that the steam pipe (8) has a fluidic connection to a cleaning liquid.

10. The method according to any one of claims 8 or 9, characterized in that the beverage maker has a brewing valve (6), which is arranged downstream of the hot water generator (3) and upstream of a brewing unit (4) of the beverage maker, wherein the brewing valve (6) is closed in the method.

11. The method according to any one of claims 8 to 10, characterized in that, in the beverage maker, a steam feed valve (11) is arranged upstream of the steam generator (5), wherein the steam feed valve (11) is closed or opened in the method.

12. The beverage maker according to any one of claims 8 to 11, characterized in that the hot water generator (3) of the beverage maker is arranged fluidically parallel to the steam generator (5), and a fluid line is arranged downstream of the hot water generator (3), said fluid line being fluidically connected via a bypass valve (12) to a fluid line that is arranged downstream of the steam generator (5), wherein, in the method, the bypass valve (12) is particularly preferably closed or opened.

13. The method according to claim 11, characterized in that the hot water generator (3) of the beverage maker, in the direction of the pump (2) and the cold water source, is arranged fluidically in series with the steam generator (5) and upstream of the steam generator (5), and, in the method, a steam feed valve (11) of the beverage maker is preferably opened or closed.

14. The method according to any one of claims 8 to 13, characterized in that the method is applied in a beverage maker according to any one of claims 1 to 7.