Coffee machine and method for operating a coffee machine

Abstract

Coffee machine (10), comprising a bean tank (14) for holding coffee beans (15); a coffee brewing system (16) with - a grinder (17) for grinding the coffee beans (15), - a brewing chamber (18) for brewing the ground coffee beans with water and - a coffee outlet (23) for discharging the brewed coffee into a coffee container (24); a grounds container (19) for collecting coffee grounds and a control unit (28) for controlling the coffee brewing system (16), characterized in that the coffee machine (10) further comprises at least two sensors (26a, 26b, 26c, 26d) on different phase elements, each in the form of an electronic nose for generating parameter-specific signals relating to the coffee beans (15), wherein the electronic noses are each a system of a plurality of gas sensors for providing a metrological representation of the composition of an air sample, which determine the concentrations of various gaseous compounds in the air; and the control unit (28) is connected to the at least two sensors (26a, 26b, 26c; 26d) and is configured to determine coffee bean parameters based on the signals received from the at least two sensors and to control the coffee brewing system (16) based on the determined coffee bean parameters.

Description

[0001] The present invention relates to a coffee machine (e.g. fully automatic coffee machine) and a method for operating a coffee machine.

[0002] Coffee machines typically contain a bean hopper for holding coffee beans and a coffee brewing system for grinding the coffee beans from the hopper and brewing the ground coffee beans with water from a water tank. The coffee brewing process depends on the coffee bean parameters (particularly the type and roast of the coffee beans), which influence the grind size, brewing time, brewing temperature, and resulting coffee quantity in order to obtain the best possible coffee product. In many conventional coffee machines, the grind size is already set before the machine is delivered, but the user then does not adjust it to the selected coffee beans placed in the hopper because they are not aware of the grind size and its adjustment options. As a result, the coffee brewing process is often not optimally adapted to the selected coffee beans, leading to a reduced quality of the coffee beverage.Since this problem is already known, there are already conventional coffee machines that contain camera sensors for reading a barcode or creating an image of the coffee beans in order to determine the type and roast of the coffee beans and adjust the coffee brewing process, as described, for example, in DE 10 2019 200 788 A1 and DE 10 2021 200 925 A1. Documents US 2017 / 0303731 A1, US 2020 / 0359830 A1, and DE 10 2015 210 338 A1 also describe coffee beans with at least one sensor on the bean tank to control the coffee brewing process based on the determined coffee bean parameters.

[0003] The object of the invention is to create a more reliable and effective variant for automatically adapting the coffee brewing process to the coffee beans inserted.

[0004] This object is achieved by the subject matter of the invention defined in independent claims 1 and 8. Some advantageous embodiments and further developments of the invention are the subject matter of the dependent claims.

[0005] According to a first aspect of the invention, the coffee machine comprises a bean tank for holding coffee beans; a coffee brewing system with a grinder for grinding the coffee beans, a brewing chamber for brewing the ground coffee beans with water, and a coffee outlet for discharging the brewed coffee into a coffee container; a grounds container for holding coffee grounds, and a control unit for controlling the coffee brewing system. According to the invention, the coffee machine further comprises at least two sensor systems on different phase elements, each in the form of an electronic nose for generating parameter-specific signals relating to the coffee beans; and the control unit is connected to the at least two sensor systems and is configured to determine coffee bean parameters based on the signals received from the at least two sensor systems and to control the coffee brewing system based on the determined coffee bean parameters.

[0006] The coffee machine can be, for example, a fully automatic coffee machine, a coffee roaster, a coffee maker, and the like. The coffee bean parameters to be determined are, in particular, the type and roast of the coffee beans, but can also include quality and shelf life. The control unit can determine the parameter data, for example, using an appropriate algorithm and / or a database comparison. The use of an electronic nose as a sensor, which creates an odor profile of the coffee beans, does not require a camera, which makes installation easier and requires less space. It can cover a large volume area and enables automated (without manual input from the user) and reliable determination of the coffee bean parameter data. Furthermore, the elimination of the camera advantageously protects the privacy of the coffee machine user.

[0007] The electronic nose is a system consisting of a multitude of gas sensors that measure the concentrations of various gaseous compounds, such as aromas, in the air. This provides a metrological representation of the composition of an air sample. The outgassing of aromas from different coffee varieties can be characterized in this way.

[0008] Furthermore, this sensor system in the form of an electronic nose can be implemented either in a single instance or, advantageously, in multiple instances in different processing phases of the coffee beans, since the electronic nose can create parameter-specific odor profiles from different processing phases of the coffee beans, whereby the control unit can also determine the parameter data (in particular variety and roast) of the coffee beans from these different odor profiles using the appropriate algorithm and / or database. In this regard, at least one sensor system can be present on the bean tank for creating the parameter-specific signals relating to the coffee beans in the bean tank and / or at least one sensor system can be present on the coffee brewing system for creating the parameter-specific signals relating to the coffee beans processed in the coffee brewing system and / or a sensor system can be present on the grounds container.The coffee brewing system can include at least one sensor on the grinder for generating parameter-specific signals relating to the coffee beans processed in the grinder, and / or at least one sensor on the brewing chamber or coffee outlet for generating parameter-specific signals relating to the coffee beans processed in the brewing chamber. Since the sensors can be arranged in the form of an electronic nose on various phase elements in the coffee machine to record the parameter data, this system can be inserted and used in at least two locations in different coffee machines. Furthermore, since it is provided here to arrange at least two sensors on different phase elements, various parameter-specific sensor signals can be generated, from which the control unit can determine the parameter data of the coffee beans even more effectively by taking the two signal evaluations into account.

[0009] The sensor system in the form of the electronic nose can also detect a variety of different gas mixtures. In one embodiment of the invention, at least one of the at least two existing sensor systems for generating the parameter-specific signals relating to the coffee beans can therefore also be positioned and configured such that it also detects gas mixtures in or from the surroundings of the coffee machine. In this case, the control unit is preferably further connected to an output element (e.g., optical and / or acoustic) for outputting a warning to the user if the at least one sensor system detects gas mixtures that are detrimental to the coffee machine.By additionally recording the gas mixture parameters using the same electronic nose, it is advantageously possible to dispense with additional special sensors for the gas mixtures, which means that no additional installation space is required and, in addition, the effort and costs of manufacturing the coffee machine can be kept lower.

[0010] The warning could, for example, be issued if substances hazardous to health are detected, such as mold in the interior of the coffee machine, particularly in the grounds container.

[0011] Advantageously, the dispensing element can also be provided with a network connection so that a warning message can be issued to a user located away from the coffee machine, for example via a mobile device.

[0012] In a preferred embodiment, the coffee machine further comprises a hot water heater for heating water. Coffee can thus be brewed with hot water. In an advantageous alternative, the hot water heater for heating water is arranged in a water tank or on the water line, preferably in the coffee brewing system.

[0013] Optionally, in addition to the at least two sensor systems in the form of the electronic nose, the coffee machine can have at least one further sensor system selected from a sensor for detecting the ambient air humidity, a sensor for detecting the moisture content of the coffee grounds, a sensor for detecting the oil content of the coffee beans in the bean tank, a sensor for detecting the oil content of the coffee beans ground in the coffee brewing system, a sensor for detecting the water content of the coffee beans in the bean tank, a sensor for detecting the water content of the coffee beans ground in the coffee brewing system, and a sensor for detecting the pH value of the water for the coffee brewing system. The control unit is also connected to this at least one further sensor system and controls the coffee brewing system according to this additional parameter data.

[0014] According to a second aspect of the invention, the method for operating a coffee machine comprises the steps of grinding coffee beans; brewing the ground coffee beans with water; and discharging the brewed coffee into a coffee container. According to the invention, the method further comprises: generating parameter-specific signals relating to the coffee beans by at least two sensors on different phase elements, each in the form of an electronic nose, wherein the electronic noses each provide a metrological representation of the composition of an air sample through a system of a plurality of gas sensors that determine the concentrations of various gaseous compounds in the air; determining coffee bean parameters based on the parameter-specific signals generated by the at least two sensors;and controlling the steps of grinding the coffee beans and brewing the ground coffee beans with water based on the determined coffee bean parameters;

[0015] With this operating method according to the invention, the same advantages can be achieved as with the coffee machine according to the invention. Regarding the advantages, the definitions, and the preferred embodiments, reference is therefore made to the above explanations regarding the coffee machine.

[0016] The parameter-specific signals relating to the coffee beans can be generated, for example, in the bean tank and / or from the treated coffee beans and / or from a coffee grounds. Furthermore, the parameter-specific signals can be generated, for example, from the ground coffee beans and / or from the coffee beans treated to produce brewed coffee.

[0017] In addition, the method may further comprise detecting gas mixtures in or from the environment of the coffee machine by at least one of the at least two sensors in the form of an electronic nose, wherein, if gas mixtures detrimental to the coffee machine are detected, a warning is output to the user by an output element (e.g. optical and / or acoustic).

[0018] In an advantageous development, the method further comprises the steps of heating water during or after grinding coffee beans; brewing the ground coffee beans with the heated water; and controlling the steps of heating water and brewing the ground coffee beans with the heated water based on the determined coffee bean parameters. In this way, a flavor-optimized coffee beverage can be prepared.

[0019] Optionally, the method may also comprise detecting at least one further parameter selected from an ambient air humidity, a humidity of the coffee grounds, an oil content of the coffee beans in the bean tank, an oil content of the ground coffee beans, a water content of the coffee beans in the bean tank, a water content of the ground coffee beans and a pH value of the water for brewing the ground coffee beans.

[0020] The invention is defined by the appended claims. The above and other features and advantages of the invention will become more apparent from the following exemplary description of a preferred, non-limiting embodiment with reference to the accompanying drawings. Therein, partly schematically, the sole Fig. 1 an embodiment of the coffee machine according to the invention.

[0021] The coffee machine 10, for example a fully automatic coffee machine, has a housing 12 in which a bean tank 14 for holding coffee beans 15, a coffee brewing system 16 for processing the coffee beans 15, and a water line 21 are arranged. In one variant of the coffee machine 10, a water tank 20 connected to the water line 21 can also be arranged in the housing 12. The coffee brewing system 16 contains a grinder 17 for grinding the coffee beans 15 from the bean tank 14 and a brewing chamber 18 for brewing the coffee beans 15 ground in the grinder 17 with cold or hot water. The water line 21 is supplied with water via a fresh water connection or from the water tank 20. The water is fed into the brewing chamber 18 via the water line 21, which contains a water pump 22. The produced brewed coffee beverage is discharged from the brewing chamber 18 via a coffee outlet 23 into a coffee container (e.g. coffee cup) 24.

[0022] To heat the water, the coffee machine 10 has a hot water heater 25, in particular a flow heater or a thermoblock, which is arranged on the water line 21 or in the water tank 21. The hot water heater 25 is preferably arranged such that it is integrated into the coffee brewing system 16.

[0023] Furthermore, in the housing 12 of the coffee machine 10 there is a grounds container 19 for receiving coffee grounds, i.e. ground coffee beans brewed with water, which are transferred from the brewing chamber 18 into the grounds container 19 after brewing.

[0024] The housing 12 of the coffee machine 10 also contains a control unit 28, which controls, in particular, the grinder 17, the brewing chamber 18, the hot water heater 25, and the water pump 22. The control unit 28 is also connected to at least two sensor systems 26a, 26b, 26c, 26d in the form of an electronic nose. According to the invention, at least two of the following sensor systems should be present in the coffee machine 10 in the form of an electronic nose.The sensor system 26a is arranged in / on the bean tank 14 in order to create parameter-specific signals relating to the coffee beans 15 in the bean tank 14 in the form of an odor profile; the sensor system 26b is arranged in / on the grinder 17 of the coffee brewing system 16 in order to create parameter-specific signals relating to the coffee beans 15 processed in the grinder 17 in the form of an odor profile; the sensor system 26c is arranged in / on the brewing chamber 18 of the coffee brewing system 16 and / or the coffee outlet 23 in order to create parameter-specific signals relating to the coffee beans 15 processed in the brewing chamber in the form of an odor profile; and the sensor system 26d is arranged in / on the grounds container 19 in order to create parameter-specific signals relating to the coffee grounds in the form of an odor profile.

[0025] The control unit 28 contains an algorithm for determining the coffee bean parameter data (in particular, the type and roast of the coffee beans 15) based on the signals received from the at least two sensors 26a-d. Optionally, the control unit 28 is also connected to a database 29 to determine the coffee bean parameter data. The control unit 28 then controls the grinder 17 and the brewing chamber 18 of the coffee brewing system 16, as well as the hot water heater 25 and the water pump 22, based on the coffee bean parameters thus determined.

[0026] The sensor system 26a in / on the bean tank 14 can generate parameter-specific signals that relate directly to the coffee beans in the bean tank 14. With regard to the other two sensors 26b, 26c, it should be noted that the ground coffee after grinding the coffee beans and the coffee product after the brewing process also exhibit parameter-specific characteristics (particularly with regard to the particularly relevant variety and roast) of the coffee beans. With regard to the sensor system 26d, comparable parameter-specific characteristics can be determined from the coffee grounds. The advantage of determining parameter-specific characteristics from the coffee grounds is that the time interval available for determining the parameter-specific characteristics is many times longer than, for example, that of the sensor system 26c (dispensing the coffee beverage), and, moreover, a time-dependent determination is possible.This allows for a finer differentiation between different coffee varieties, as aromas develop over time. The sensor signals from the various sensor systems 26a-d are naturally slightly different, but the control unit 28 recognizes which phase it is receiving the signals from and can still correctly determine the coffee bean parameters using an appropriately adapted algorithm and / or a correspondingly expanded / adapted database 29.

[0027] As in Fig.As indicated in Figure 1, the control unit 28 can also be coupled to an output element (optical and / or acoustic, or digital) 30. The output element 30 can also be provided with a network connection (not shown), so that a warning can be issued to a user located remotely from the coffee machine 10, for example, via a mobile device. In particular, the sensor system 26a on / in the bean tank 14 can, in addition to generating the parameter-specific signals relating to the coffee beans 15 in the form of an odor profile, be positioned and configured such that it can also detect gas mixtures in or from the surroundings of the coffee machine 10.If this one sensor 26a detects gas mixtures that are detrimental to the coffee machine in this way, the control unit 28, based on the corresponding signal received from the sensor 26a, outputs a corresponding warning to the user of the coffee machine 10 via the output element 30 so that the user can improve the situation of the coffee machine and / or its environment as much as possible.

[0028] Although not shown, the coffee machine can optionally further comprise at least one further sensor system selected from a sensor for detecting the ambient air humidity, a sensor for detecting the moisture content of the coffee grounds, a sensor for detecting the oil content of the coffee beans 15 in the bean tank 14, a sensor for detecting the oil content of the coffee beans ground in the coffee brewing system 16, a sensor for detecting the water content of the coffee beans in the bean tank 14, a sensor for detecting the water content of the coffee beans ground in the coffee brewing system 16, and a sensor for detecting the pH value of the water for the coffee brewing system 16.

[0029] The quality of a coffee beverage can be influenced not only by the coffee beans 15 used but also by the following parameters: by the degree of grinding of the ground coffee beans, by the quantity of ground coffee beans used, by the temperature of the water, by the water pressure acting on the ground coffee beans and generated by the water pump 22 and by the flow time of the water through the ground coffee beans in the brewing chamber 18. The control unit 28 is capable of controlling each of the above parameters individually as well as a combination of some or all of the above parameters in such a way as to obtain a coffee beverage with an optimized taste.

[0030] The invention is defined by the appended claims. The exemplary embodiment explained above serves only to facilitate a better understanding of the invention, but is not intended to limit the scope of protection defined by the claims. As will be apparent to those skilled in the art, other embodiments are also possible within the scope of the invention, in particular by omitting individual features from or adding additional features to the exemplary embodiment described above. REFERENCE NUMBER LIST 10 coffee machines (e.g. fully automatic coffee machines) 12 housings 14 Bean tank 15 coffee beans 16 coffee brewing system 17 Grinder 18 Brewing chamber 19 pomace containers 20 water tank 21 Water pipe 22 Water pump 23 Coffee outlet 24 coffee containers 25 hot water heaters 26a Sensors on 14 26b Sensors on 17 26c Sensors on 18 or 23 26d Sensors on 19 28 Control unit 29 Database 30 Output element

Claims

[1] Coffee machine (10), comprising a bean tank (14) for holding coffee beans (15); a coffee brewing system (16) with - a grinder (17) for grinding the coffee beans (15), - a brewing chamber (18) for brewing the ground coffee beans with water and - a coffee outlet (23) for discharging the brewed coffee into a coffee container (24); a grounds container (19) for collecting coffee grounds and a control unit (28) for controlling the coffee brewing system (16), characterized by , that the coffee machine (10) further comprises at least two sensors (26a, 26b, 26c, 26d) on different phase elements, each in the form of an electronic nose for generating parameter-specific signals relating to the coffee beans (15), wherein the electronic noses are each a system of a plurality of gas sensors for providing a metrological representation of the composition of an air sample, which determine the concentrations of various gaseous compounds in the air; and the control unit (28) is connected to the at least two sensors (26a, 26b, 26c; 26d) and is configured to determine coffee bean parameters based on the signals received from the at least two sensors and to control the coffee brewing system (16) based on the determined coffee bean parameters. [2] Coffee machine (10) according to claim 1, wherein the at least two sensor systems (26a, 26b, 26c, 26d) comprise a sensor system (26a) on the bean tank (15) for generating the parameter-specific signals relating to the coffee beans (15) in the bean tank (14) and / or at least one sensor system (26b, 26c) on the coffee brewing system (16) and / or a sensor system (26d) on the grounds container (19) for generating the parameter-specific signals relating to the coffee beans (15) treated in the coffee brewing system (16). [3] Coffee machine (10) according to claim 1 or 2, wherein the at least two sensors (26a, 26b, 26c, 26d) comprise a sensor (26b) on the grinder (17) for generating the parameter-specific signals relating to the coffee beans (15) treated in the grinder (17) and / or a sensor (26c) on the brewing chamber (18) or the coffee outlet (23) for generating the parameter-specific signals relating to the coffee beans (15) treated in the brewing chamber (16). [4] Coffee machine (10) according to one of the preceding claims, wherein at least one sensor system (26a) of the at least two sensor systems (26a, 26b, 26c, 26d) for generating the parameter-specific signals relating to the coffee beans (15) is further positioned and configured to also detect gas mixtures in or from the environment of the coffee machine (10); and the control unit (28) is further connected to an output element (30) for outputting a warning to the user when the at least one sensor system (26a) detects gas mixtures that are detrimental to the coffee machine. [5] Coffee machine (10) according to one of the preceding claims, further comprising a hot water heater (25) for heating water. [6] Coffee machine (10) according to claim 5, wherein the hot water heater (25) for heating water is arranged in a water tank (20) or on the water line (21), preferably in the coffee brewing system (16). [7] Coffee machine (10) according to one of the preceding claims, which further comprises at least one further sensor system selected from a sensor for detecting the ambient air humidity, a sensor for detecting the moisture content of the coffee grounds, a sensor for detecting the oil content of the coffee beans (15) in the bean tank (14), a sensor for detecting the oil content of the coffee beans ground in the coffee brewing system (16), a sensor for detecting the water content of the coffee beans (15) in the bean tank (14), a sensor for detecting the water content of the coffee beans ground in the coffee brewing system (16), and a sensor for detecting the pH value of the water for the coffee brewing system (16). [8] Method for operating a coffee machine (10), comprising: Grinding coffee beans (15); Brewing the ground coffee beans with water; and Pouring the brewed coffee into a coffee container (24), characterized bythat the method further comprises: Creating parameter-specific signals relating to the coffee beans (15) by at least two sensors (26a, 26b, 26c, 26d) at different phase elements, each in the form of an electronic nose, wherein the electronic noses each provide a metrological representation of the composition of an air sample by means of a system comprising a plurality of gas sensors which determine the concentrations of different gaseous compounds in the air; Determining coffee bean parameters based on the parameter-specific signals generated by the at least two sensors (26a, 26b, 26c, 26d); and Controlling the steps of grinding the coffee beans (15) and brewing the ground coffee beans with water based on the determined coffee bean parameters. [9] Method according to claim 8, wherein the parameter-specific signals relating to the coffee beans (15) in the bean tank (14) and / or from the treated coffee beans and / or from a coffee grounds are generated. [10] Method according to claim 8 or 9, wherein the parameter-specific signals relating to the ground coffee beans and / or relating to the coffee beans treated to produce brewed coffee are generated. [11] Method according to one of claims 8 to 10, further comprising: Detecting gas mixtures in or from the environment of the coffee machine (10) by at least one of the at least two sensors (26a, 26b, 26c, 26d) in the form of an electronic nose; and Outputting a warning to the user by an output element (30) when gas mixtures detrimental to the coffee machine (10) are detected. [12] Method according to one of claims 8 to 11, further comprising: Heating water during or after grinding coffee beans (15); brewing the ground coffee beans with the heated water; and Controlling the steps of heating water and brewing the ground coffee beans with the heated water based on the determined coffee bean parameters. [13] Method according to one of claims 8 to 12, further comprising detecting at least one further parameter selected from an ambient air humidity, a humidity of the coffee grounds, an oil content of the coffee beans (15) in the bean tank, an oil content of the ground coffee beans, a water content of the coffee beans (15) in the bean tank, a water content of the ground coffee beans and a pH value of the water for brewing the ground coffee beans.

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