METHOD FOR OPERATING A HOT DRINKS MACHINE AND HOT DRINKS MACHINE

Description

[0001] The invention relates to a method for operating a hot drinks machine, a control device and a hot drinks machine according to the main claims.

[0002] With a freestanding fully automatic coffee machine, a milk container, such as a coated paper container or a stainless steel jug, can be placed next to the machine. A hose can be connected to a spout to draw in the milk. The milk can be mixed with hot steam from the machine to create milk foam. In DE 10 2016 107 086 A1, the filling of a drinking vessel is monitored by a camera. This records the dispensed quantity or the fill level in the drinking vessel.

[0003] From WO 2019 / 180 252 A1, a beverage maker is known which has a camera device arranged at a dispensing area and is designed to record images of the dispensing area in order to record a process carried out there.

[0004] The object of the invention is to provide an improved method for operating a hot drinks machine, an improved control device and an improved hot drinks machine.

[0005] According to the invention, this object is achieved by a method for operating a hot drinks vending machine, a control device, and a hot drinks vending machine having the features of the main claims. Advantageous embodiments and further developments of the invention are set forth in the following subclaims.

[0006] The advantages achieved with the invention include detecting malfunctions during beverage dispensing and detecting an empty milk container, as well as pausing the milk frothing process if necessary. This prevents excessive steam buildup in the device and the associated damage to the electronics. Furthermore, it can prevent people from getting burned by uncontrolled hot steam.

[0007] A method for operating a hot drinks machine with a milk foam generating device for generating milk foam is presented, the method comprising the following steps: detecting an operation at a dispensing area of the hot drinks machine by means of a camera device which is arranged at the dispensing area and is designed to record images of the dispensing area,

[0008] Outputting a camera signal to a control device, wherein the camera signal represents an operation performed at the output area and

[0009] Providing a shutdown signal for switching off the milk foam generating device in response to the camera signal if the camera signal represents or depicts a steam condition in which a reference point of the output area can no longer be detected and / or recognized by the camera device.

[0010] The hot drinks machine could, for example, be a fully automatic coffee machine that includes a device for frothing milk for preparing various hot drinks, such as cappuccino. A milk substitute, such as a liquid based on soy, almonds, or oats, could be used instead of milk. To create milk foam, a tetra pack or a stainless steel jug could be placed next to the machine. A hose can lead from one of the hot drinks machine's outlets, through which the milk can be sucked in, for example using the Venturi principle. In the outlet, the milk can be mixed with hot steam from the machine. The steam-milk mixture can be directed, for example, via outlet nozzles into a container located below the outlet, such as a cup. The amount of milk foam drawn can be regulated over time, for example.This can be individually adjusted by the user, for example for a duration of 1.5 minutes. In the hot drinks machine presented here, the process of dispensing milk foam or the dispensing of drinks is recorded at the dispensing area, for example an area below the spout. When the milk foam is dispensed, a uniform cloud of steam is created, through which a camera in the camera system can still see. Objects behind it, such as a cup, are still blurred. As soon as the milk is empty, the cloud of steam becomes significantly more uneven and, above all, opaque. As soon as the camera can no longer see through it, this state has been reached, which is referred to here as the steam state and is transmitted to the control unit via the camera signal.The control device, which can also be referred to as the appliance control, immediately stops the milk foam dispensing process, for example by switching off a pump. The same or a similar process also occurs if the milk gets too hot, for example. Milk that is too hot can no longer be frothed because the protein denatures. It can then spray and steam from the nozzles just like an empty milk container. In addition, it can smell and taste burnt and the milk foam can immediately collapse. The method presented here advantageously means that the appliance automatically detects when the milk container is empty before the preparation time has elapsed. This can prevent only air and steam from mixing together, which would result in steam and spraying from the spout and, for example, becoming extremely loud.The process is therefore paused even if no one is nearby to manually interrupt it. This prevents the entire device from being exposed to steam and then having to be thoroughly dried. This advantageously prevents damage to the electronics caused by the steaming and also prevents children, for example, who may be unsupervised near the device at that time from being burned by the steam.

[0011] According to one embodiment, a warning signal for activating a warning message can be provided in the providing step if the camera signal represents or depicts the steam state. The warning message can, for example, take the form of an activated light unit or the display of text on a display of the hot drinks machine. Additionally or alternatively, the control device can be designed to establish a wireless connection, for example via WLAN or Bluetooth, with a user's mobile device. For example, a corresponding message can be sent to the mobile device if the opaque milk container, for example, is empty. Advantageously, a user of the hot drinks machine can thus be quickly informed if intervention at the hot drinks machine is required.

[0012] According to one embodiment, a beverage stream can be detected in the detecting step. In this case, a cleaning signal for cleaning the dispensing area can be provided in the providing step if the beverage stream deviates from an expected shape. For example, the expected shape can be a uniform beverage stream that is directed vertically downwards from a spout into a cup. If, for example, the spout is blocked, e.g. by dirt or limescale deposits, then the beverage stream can deviate from such an expected shape. Such a change can be detected by the camera device, and a corresponding cleaning signal can be provided by the control device. In this case, the cleaning signal can, for example, trigger automatic cleaning of the hot beverage machine or, for example, provide a user with a prompt for manual cleaning, e.g. via a display.Advantageously, this allows contamination in the dispensing area to be quickly detected and removed.

[0013] According to one embodiment, the cleaning signal can be provided when a dripping beverage stream is detected. For example, the camera device can detect that the beverage stream is no longer flowing smoothly, but rather intermittently, i.e., dripping. In such a case, a cleaning signal can advantageously be provided to quickly remove a possible blockage in the dispensing area.

[0014] According to one embodiment, the cleaning signal can be provided when the detected beverage stream deviates from a predetermined and / or expected flow direction.

[0015] For example, the camera device can detect that the beverage stream deviates from an expected flow direction, such as vertically downwards, and is flowing in a direction that is oblique compared to the expected flow direction. In such a case, a cleaning signal can advantageously be provided to quickly remove any blockage in the dispensing area.

[0016] According to one embodiment, in the detection step, a further dispensing area of the hot drinks machine can be detected by means of the camera device. In the dispensing step, the camera signal can represent a process performed at the dispensing area and additionally or alternatively at the further dispensing area, and in the providing step, the shutdown signal can be provided if the camera signal represents or maps the steam state in which the reference point of the dispensing area and additionally or alternatively a further reference point of the further dispensing area can no longer be detected and / or recognized by the camera device. For example, the hot drinks machine can comprise two dispensing areas in which two hot drinks can be dispensed or prepared in parallel.The camera device can, for example, be arranged centrally between the two dispensing areas and be designed to simultaneously detect both dispensing areas, or, for example, two cups arranged in the dispensing areas. If, for example, a steam condition is detected in one of the two dispensing areas or simultaneously in both dispensing areas, for example due to an empty milk container, the shutdown signal for shutting down the milk foam generation device can be provided. Advantageously, this allows monitoring of a plurality of parallel hot beverage preparation processes.

[0017] According to one embodiment, a correction signal for correcting at least one brewing parameter can be provided in the providing step if the beverage stream detected by the camera and a further beverage stream detected in the wider dispensing area deviate from an expected shape. For example, the camera device can detect that the beverage stream is only dripping. If this is detected in only one dispensing area, a notification can be issued to a user, for example, that the spout should be cleaned. If, for example, simultaneous dripping is detected in both dispensing areas, this can be due to a lack of water or an incorrect setting of the grinding quantity or degree of grinding. In this case, the correction signal can advantageously be provided in order to have these parameters checked manually or to correct them directly and automatically.

[0018] The approach presented here further provides a control device configured to perform, control, or implement the steps of a variant of a method presented here in corresponding devices. This embodiment of the invention in the form of a control device also allows the problem underlying the invention to be solved quickly and efficiently.

[0019] The control device can be designed to read in input signals and to determine and provide output signals using the input signals. An input signal can, for example, represent a sensor signal that can be read in via an input interface of the device. An output signal can represent a control signal or a data signal that can be provided at an output interface of the device. The control device can be designed to determine the output signals using a processing rule implemented in hardware or software. For example, the device can comprise a logic circuit, an integrated circuit, or a software module and can, for example, be implemented as a discrete component or be comprised of a discrete component.

[0020] Furthermore, a hot beverage vending machine with a milk foam generating device for generating milk foam is presented, wherein the hot beverage vending machine has a camera device arranged at the dispensing area for dispensing a beverage stream and configured to record images of the dispensing area. The camera device is configured to detect a process performed at the dispensing area and to provide a camera signal representing the process. Furthermore, the hot beverage vending machine comprises a control device configured to provide, in response to the camera signal, a shutdown signal for shutting down the milk foam generating device if the camera signal represents or depicts a vapor state in which a reference point of the dispensing area can no longer be detected and / or recognized by the camera device.

[0021] Also advantageous is a computer program product or computer program with program code that can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory, or an optical memory. If the program product or program is executed on a control device of a hot beverage vending machine, the program product or program can be used to carry out, implement, and / or control the steps of the method according to one of the embodiments described above.

[0022] An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows Figure 1 shows a schematic representation of a hot drinks machine according to an embodiment; Figure 2 shows a flow diagram of an embodiment of a method for operating a hot drinks machine; Figure 3 shows a schematic representation of a hot drinks machine according to an embodiment; Figure 4 shows a schematic representation of a milk foam generating device according to an embodiment; Figure 5 shows a schematic representation of a milk foam generating device according to an embodiment; Figure 6 shows a schematic representation of a milk foam generating device according to an embodiment; and Figure 7 shows a diagram of an embodiment of a process for preparing milk foam.

[0023] Figure 1shows a schematic representation of a hot drinks machine 100 according to an embodiment. For example only, the hot drinks machine 100 shown here is a freestanding fully automatic coffee machine. In this embodiment, the hot drinks machine 100 comprises a milk foam generating device 105 for generating milk foam. For this purpose, the milk foam generating device 105 is connected via a hose 110 to a milk container 115, which, for example only, is a plastic-coated paper packaging such as a Tetra Pak package. In this embodiment, the milk foam generating device 105 is designed to suck milk from the milk foam container 115 using the Venturi principle and mix it with hot steam. The steam-milk mixture can be guided via the outlet nozzles 120 into a container 125, which in this embodiment is a cup.For this purpose, the container 125 is arranged in a dispensing area 130 below the outlet nozzles 120. The amount of milk foam dispensed can be regulated over time, merely as an example. This can be set manually and, in this exemplary embodiment, has a duration of up to 1.5 minutes. In this exemplary embodiment, the hot drinks machine 100 cannot detect whether the milk container 115 contains liquid or is empty. If the milk container 115 is empty and the preparation time has not yet elapsed, a mixture of air and steam is created. This leads to steam and splashing in the dispensing area 130 and it becomes extremely loud. If no one is nearby to interrupt the process, the entire device is exposed to steam, which leads to damage to the electronics.

[0024] Figure 2shows a flowchart of an embodiment of a method 200 for operating a hot drinks machine with a milk foam generating device for generating milk foam. The method 200 comprises a step 205 of detecting a process at a dispensing area of the hot drinks machine by means of a camera device that is arranged at the dispensing area and designed to record images of the dispensing area. By way of example only, the detectable process is a cloud of steam created when milk foam is generated. In another embodiment, a dispensed beverage stream can also be detected. The process is detected by the camera device and, in step 210 of dispensing, transmitted to a control device of the hot drinks machine by means of a camera signal. The camera signal represents the process performed at the dispensing area.In step 215 of providing, for example, a shutdown signal is provided in response to the camera signal in order to switch off the milk foam generating device if the camera signal represents a steam state in which a reference point of the dispensing area can no longer be detected by the camera device. In this exemplary embodiment, the reference point is a vessel arranged in the dispensing area for receiving the milk foam. In other words, the method can be described as follows. During normal milk foam dispensing, steam is created in a uniform cloud through which the camera can still see. Objects behind it are still blurred. As soon as the milk in the milk vessel is empty, the steam cloud becomes significantly more irregular and, above all, more opaque. As soon as the camera can no longer see through it, it sends a signal to the device control.This immediately switches off the pump, which stops the milk foam dispensing. In this way, an empty milk container is detected and dispensing is stopped immediately. This prevents the device from becoming extremely steamy, which could also damage the electronics. There is also no risk of people being burned by the uncontrolled hot steam. In this exemplary embodiment, in step 215 of providing, a warning signal for activating a warning message is also provided if the camera signal represents the steam state. In this case, a message is merely output to a user, by way of example, that the milk container is empty. In another exemplary embodiment, a beverage stream can also be detected in the detecting step, wherein in the providing step, a cleaning signal for cleaning the dispensing area can be provided if the beverage stream deviates from an expected shape.Additionally or alternatively, in the step of providing, a correction signal for correcting at least one brewing parameter can be provided if the beverage jet detected by the camera and a further beverage jet detected in a further dispensing area deviate from an expected shape.

[0025] Figure 3 shows a schematic representation of a hot drinks machine 100 according to an embodiment. The hot drinks machine 100 shown here corresponds to or is similar to the one shown in the previous Figure 1 described hot drinks machines, with the

[0026] Difference that a procedure as described in the previous Figure 2described, can be carried out with the hot drinks machine 100 shown here. The hot drinks machine 100 comprises a milk foam generating device 105 for generating milk foam. For this purpose, the milk foam generating device 105 is connected, merely by way of example, via a hose 110 to a milk container 115, which in this exemplary embodiment is a stainless steel jug. The milk foam generating device 105 is designed to suck liquid from the milk container 115 via a Venturi tube 300. In addition, the hot drinks machine 100 comprises a water tank 305 for storing water and is designed to pump water from the water tank 305 by means of a pump 310 via a flowmeter or flow measuring device 315, a heating element 320 and a valve unit 325.The water can be heated by means of the heating element 320 and the resulting water vapor can be mixed with milk taken from the milk container 115 by the milk foam generating device 105 in order to produce milk foam.

[0027] The hot beverage machine 100 also has a camera device 330, which is arranged at the dispensing area 130 and configured to capture images of the dispensing area 130. The camera device 330 is configured to capture a process performed at the dispensing area 130 and to provide a camera signal 335 representing the process to a control device 340 of the hot beverage machine 100. The control device 340 comprises a processor 342 and a memory 344 and is configured to provide, in response to the camera signal 335, a shutdown signal 345 for shutting off the milk foam generating device 105 if the camera signal 335 represents a vapor state in which a reference point of the dispensing area 130 can no longer be detected by the camera device 330. For example only, the reference point in this exemplary embodiment corresponds to a vessel 125 arranged in the dispensing area 130.The steam state is reached as soon as the milk container 115 is empty, and as a result, a steam cloud generated by the milk foam generation device 105 is uneven and opaque. Additionally, the steam state can be reached when milk drawn from the milk container 115 is too hot. Milk that is too hot can no longer be frothed because the protein denatures. Steam sprays from the nozzles and emits the same odor as from an empty milk container. Additionally, it smells and tastes burnt, and the milk foam immediately collapses. During the steam state, the reference point, i.e., the container 125, can no longer be detected by the camera device 330. The steam state can be transmitted to the control device 340 using the camera signal 335. To abort the milk frothing process, the control device 340 is designed in this embodiment to provide the shutdown signal to the pump 310.The suspension of the pump 310 prevents the device from continuing to try to suck in milk despite the milk container 115 being empty, thus steaming and soiling the entire device.

[0028] In this exemplary embodiment, the control device 340 is also designed to provide a warning signal 350 to a warning unit 355 in response to the camera signal 335 for activating a warning message if the camera signal 335 represents the steam condition. For example only, the warning message is a signal light designed to illuminate in response to the warning signal 350. In addition to detecting a steam condition, the camera device 330 in this exemplary embodiment is designed to detect a beverage stream dispensed in the dispensing area 130, which can be generated by a brewing unit 360 of the hot beverage machine 100. The control device 340 is designed to provide a cleaning signal 365 for cleaning the dispensing area 130 if the beverage stream deviates from an expected shape.

[0029] Figure 4shows a schematic representation of a milk foam generating device 105 according to an embodiment. The milk foam generating device 105 shown here corresponds to or is similar to the device shown in the previous Figures 1 and 3described milk foam generating device, with the difference that in the illustration shown here, a further output area 400 is arranged below the milk foam generating device 105 next to the output area 130. In this exemplary embodiment, both output areas 130, 400 can be captured simultaneously by the camera device 330. In the illustration shown here, the milk foam generating device 105 is depicted in a vapor state in which, due to an empty milk container 115, a vapor cloud 405 is arranged in the output area 130 and a further vapor cloud 410 is arranged in the further output area 400. Due to the opaque vapor clouds 405, 410, a vessel 125 arranged in the output area 130 and a further vessel 415 arranged in the further output area 400 can no longer be captured by the camera device 330.In this case, the vessel 125 corresponds merely by way of example to a reference point of the output region 130 and the further vessel 415 corresponds to a further reference point of the further output region 400. The camera device 330 is designed in this exemplary embodiment in order to . Figure 3 to provide the camera signal described, which merely represents, by way of example, the detected steam state in both output areas 130, 400.

[0030] Figure 5 shows a schematic representation of a milk foam generating device 105 according to an embodiment. The milk foam generating device 105 shown here corresponds to or is similar to the device shown in the previous Figures 1 , 3 and 4described milk foam generating device. In this case, beneath the milk foam generating device 105, both an output region 130 and a further output region 400 are arranged, both of which can be captured by the camera device 330. In the illustration shown here, the camera device 330 captures a process of dispensing a beverage jet 500 into a vessel 125 arranged in the output region 130, as well as a process of dispensing a further beverage jet 505 into a further vessel 415 arranged in the further output region 400. In this exemplary embodiment, the camera device 330 is designed to transmit the shape of the captured beverage jets 500, 505 to the control device 340 using the camera signal 335. In the illustration shown here, the beverage jet 500 deviates from an expected shape and is captured as a dripping beverage jet.The control device 340 is configured to provide a cleaning signal 365 for cleaning the dispensing area 130 in response to the camera signal 335 representing the dripping beverage stream 500. Furthermore, in this exemplary embodiment, the control device 340 is configured to provide a correction signal 510 if both the beverage stream 500 and the further beverage stream 505 deviate from an expected shape. In response to the correction signal 510, the hot beverage dispenser is configured, merely by way of example, to automatically correct at least one brewing parameter. Thus, in this exemplary embodiment, the device detects deficiencies in the brewing parameters due to poor coffee flow and can independently readjust the parameters.In another embodiment, in response to the correction signal, instead of an automatic correction, a notification can be issued to a user to check the set grinding quantity or degree of grinding.

[0031] Figure 6 shows a schematic representation of a milk foam generating device 105 according to an embodiment. The milk foam generating device 105 shown here corresponds to or is similar to the device shown in the previous Figures 1 , 3 , 4 and 5described milk foam generating device. In this case, beneath the milk foam generating device 105, both an output region 130 and a further output region 400 are arranged, both of which can be captured by the camera device 330. In the illustration shown here, the camera device 330 captures a process of dispensing a beverage jet 500 into a vessel 125 arranged in the output region 130, as well as a process of dispensing a further beverage jet 505 into a further vessel 415 arranged in the further output region 400. In this exemplary embodiment, the camera device 330 is designed to transmit the shape of the captured beverage jets 500, 505 to the control device 340 using the camera signal 335. In the illustration shown here, the beverage jet 500 deviates from a predetermined flow direction and is captured as an oblique beverage jet.The control device 340 is configured to provide a cleaning signal 365 for cleaning the dispensing area 130 in response to the camera signal 335 representing the skewed beverage stream 500. Furthermore, in this exemplary embodiment, the control device 340 is configured to provide a correction signal 510 if both the beverage stream 500 and the additional beverage stream 505 deviate from an expected flow direction. In response to the correction signal 510, the hot beverage machine is configured, merely by way of example, to output a notification to a user to check the set grinding quantity or degree of grinding.

[0032] Figure 7shows a diagram of an embodiment of a process 700 for preparing milk foam. The process 700 is shown as a diagram in sub-figure 7A on the left side of the figure, while in sub-figure 7B on the right side, a hot drinks machine 100 is shown in which the process 700 can be carried out. The hot drinks machine 100 shown here corresponds to or is similar to the one shown in the previous Figures 1 and 2described hot beverage machines. In the diagram of sub-figure 7A, the x-axis corresponds to the time of the process 700 in seconds and the y-axis to the temperature used in degrees Celsius. In the illustration shown here, milk is heated to 65°C, for example, and after about 60 seconds, it is mixed with steam to prepare milk foam. After about 120 seconds, the milk is used up in this embodiment, leaving only air and steam to mix with each other. As a result, the device begins to spray, hiss, and produce steam in an uncontrolled manner, which is represented in sub-figure 7B by the steam cloud 405 shown. In another embodiment, a method as described in the previous Figure 2 described above, to interrupt the process and prevent uncontrolled steaming of the hot drinks machines.

Claims

1. Method (200) for operating a hot beverage machine (100) comprising a milk foam generating device (105) for generating milk foam, the method (200) being characterised by the following steps: detecting (205) a process at a dispensing region (130) of the hot beverage machine (100) by means of a camera device (330) arranged at the dispensing region (130) and designed to record images of the dispensing region (130); outputting (210) a camera signal (335) to a control device (340), the camera signal (335) representing a process performed at the dispensing region (130); and providing (215) a switch-off signal (345) for switching off the milk foam generating device (105) in response to the camera signal (335) if the camera signal (335) depicts a steam state in which a reference point (125) of the dispensing region (130) can no longer be detected and / or recognised by the camera device (330).

2. Method (200) according to claim 1, wherein in the step (215) of providing, a warning signal (350) is provided for activating a warning message if the camera signal (335) depicts the steam state.

3. Method (200) according to either of the preceding claims, wherein in the step (205) of detecting, a beverage jet (500) is detected and wherein in the step (215) of providing, a cleaning signal (365) for cleaning the dispensing region (130) is provided if the beverage jet (500) deviates from an expected shape.

4. Method (200) according to claim 3, wherein the cleaning signal (365) is provided if a dripping beverage jet (500) is detected.

5. Method (200) according to claim 3 or 4, wherein the cleaning signal (365) is provided if the detected beverage jet (500) deviates from a predetermined and / or expected flow direction.

6. Method (200) according to any of the preceding claims, wherein in the step (205) of detecting, a further dispensing region (400) of the hot beverage machine (100) is detected by means of the camera device (330), wherein in the step (210) of outputting, the camera signal (335) represents a process performed at the dispensing region (130) and / or at the further dispensing region (400), and wherein in the step (215) of providing, the switch-off signal (345) is provided if the camera signal (335) depicts the steam state in which the reference point (125) of the dispensing region (130) and / or a further reference point (415) of the further dispensing region (400) can no longer be detected and / or recognised by the camera device (330).

7. Method (200) according to any of the preceding claims, wherein in the step (215) of providing, a correction signal (510) for correcting at least one brewing parameter is provided if the beverage jet (500) detected by the camera device (330) and a further beverage jet (505) detected in the further dispensing region (400) deviate from an expected shape.

8. Hot beverage machine (100) comprising a milk foam generating device (105) for generating milk foam, the hot beverage machine (100) having the following features: a camera device (330) arranged at a dispensing region (130) for dispensing a beverage jet (500) and designed to record images of the dispensing region (130), the camera device (330) being designed to detect a process performed at the dispensing region (130) and to provide a camera signal (335) representing the process; characterised by a control device (340) which is designed to provide, in response to the camera signal (335), a switch-off signal (345) for switching off the milk foam generating device (105) if the camera signal (335) depicts a steam state in which a reference point (125) of the dispensing region (130) can no longer be detected and / or recognised by the camera device (330).

9. Hot beverage machine (100) according to claim 8, wherein the control device (340) is designed to carry out the steps (205, 210, 215) of the method according to any of claims 1 to 7.

10. Computer program product comprising program code for carrying out the method (200) according to any of the preceding claims 1 to 7 when the computer program product is run on a control device (340) of a hot beverage machine (100) according to claim 8 or 9.

11. Machine-readable storage medium on which the computer program according to claim 10 is stored.