EP3496509B1 - Cooking device - Google Patents

Description

The invention relates to a cooking appliance device according to the preamble of claim 1.

From the prior art, for example from the publication WO 2017/103713 A1 , a cooking appliance device designed as an induction hob device is already known, which has a heating unit designed as an induction heating unit. In an operating state, a sensor unit of the cooking appliance device detects a main signal of a signal influenced by the heating unit, specifically by means of a sensor element designed as a resistance sensor. The sensor unit detects the main signal of the signal temporally in a range of a zero crossing of a mains voltage in order to minimize an interference signal superimposed on the main signal of the signal. It is also known to minimize an interference signal superimposed on the main signal of the signal by forming an average value from several measurements. A control unit of the cooking appliance device determines a temperature of the heating unit from the main signal detected by the sensor unit and an activity state of the heating unit from the determined temperature. Such a determination of the activity state of the heating unit is time-consuming and error-prone, which can result in a potential safety risk for an operator due to an incorrect assumption with regard to the activity level of the heating unit.

Furthermore, from the publication EP 0 717 581 A1 an induction hob device with a heating unit and with a sensor unit for detecting pot positioning is known.

The document also discloses US 2011/168697 A1 also an induction hob device with a heating unit and with a sensor unit which measures a current flowing between an inverter and a capacitor in order to avoid voltage fluctuations and to stabilize a current flow to the heating unit.

In addition to a power converter, the publication discloses US 2011/168697 A1 a control device with overvoltage protection.

Next is from the pamphlet EP 2 911 473 A1 an induction hob device with a plurality of heating units and a plurality of sensor units, which are designed as infrared sensors for temperature detection, are known.

The object of the invention is in particular to provide a device of the generic type with improved properties with regard to properties of activity determination. The object is achieved according to the invention by the features of claim 1, while advantageous configurations and developments of the invention can be found in the subclaims.

The invention is based on a cooking device device, in particular an induction cooking device device and advantageously an induction hob device, with at least one heating unit, with at least one sensor unit, which is provided for the detection of at least one signal influenced by the heating unit, and with at least one control unit that is responsible for this it is provided to determine at least one degree of activity of the heating unit from an interference signal superimposed on a main signal of the signal, with at least one switching unit (26) which is provided to establish and interrupt at least one current path to the heating unit (12), the control unit ( 16) is provided to check a function of the switching unit (26) on the basis of the interference signal.

The configuration according to the invention makes it possible, in particular, to achieve advantageous properties with regard to activity determination. In particular, a high level of operational reliability and / or a high level of safety for an operator can be achieved, since in particular a probability of a malfunction of a heating unit can be avoided. In particular, a quick and / or reliable determination of the degree of activity can be made possible. In particular, an additional sensor unit and / or a change in an arrangement of the sensor unit can be dispensed with, as a result of which, in particular, a cost-effective design can be achieved. In particular, low development costs can be achieved, since the degree of activity can be determined in a simple manner using the interference signal. Such a configuration according to claim 1 can in particular be transferred to all common cooking appliances of a brand and / or a manufacturer, which in particular enables a high degree of flexibility.

A "cooking device", in particular an "induction cooking device" and advantageously an "induction hob device", should be understood to mean in particular at least one part, in particular a subassembly, of a cooking device, in particular an induction cooking device and advantageously an induction hob. For example, a cooking device having the cooking device device could be, for example, an oven and / or a microwave and / or a grill device and / or a steam cooking device. A cooking device having the cooking device device is advantageously a hob and preferably an induction hob.

In this context, a “heating unit” is to be understood in particular as a unit which is provided in at least one operating state to supply energy to at least one cookware for the purpose of heating the cookware. For example, the heating unit could be designed as a resistance heating unit and in particular be provided to convert energy into heat and to supply this to the cookware for the purpose of heating the cookware. Alternatively or additionally, the heating unit could be designed as an induction heating unit and in particular be provided to supply energy to the cookware in the form of an electromagnetic alternating field, wherein the energy supplied to the cookware could be converted into heat, in particular in the cookware.

The cooking appliance device has, in particular, at least one further heating unit which, in particular, is different from the heating unit and is advantageously arranged adjacent to the heating unit. For example, the cooking appliance device could have at least two, in particular at least three, advantageously at least four, particularly advantageously at least six, preferably at least ten and particularly preferably a plurality of further heating units, which in particular could be designed differently from the heating unit and advantageously arranged adjacent to the heating unit. In particular, the heating unit and the further heating unit (s) could be arranged in the form of a matrix.

The cooking appliance device has, in particular, at least one supply unit, which is provided in particular in at least one operating state to supply the heating unit and / or the further heating unit. The supply unit has in particular at least one inverter. In particular, the supply unit has at least two, in particular at least three, advantageously at least four, particularly advantageously at least six, preferably at least ten and particularly preferably a large number of inverters. For example, a number of inverters and a number of heating units could be the same. Alternatively, a number of inverters could be greater than a number of heating units, for example. A number of inverters is advantageously smaller than a number of heating units, as a result of which, in particular, low costs can be achieved.

A "sensor unit" is to be understood in particular as a unit which has at least one detector for detecting at least one sensor parameter and which is provided to output a value characterizing the sensor parameter, the sensor parameter advantageously being a physical and / or chemical one Size matters. The signal is advantageously an electrical and / or an electronic signal. In at least one operating state, the sensor unit detects in particular the signal influenced by the heating unit. In particular, the sensor unit has at least one sensor element which in particular could be assigned to the heating unit and / or the further heating unit. For example, the sensor unit could have at least two, in particular at least three, advantageously at least four, particularly advantageously at least six, preferably at least ten and particularly preferably a plurality of sensor elements, which in particular each have one of the heating units, in particular the heating unit and / or one of the further heating units, assigned could be. For example, a number of sensor elements and a number of heating units could be the same.

The signal could, for example, be an electrical voltage applied to the sensor unit, in particular to the sensor element of the sensor unit. Alternatively or additionally, the signal could be an electrical current flowing in particular through the sensor unit, in particular through the sensor element of the sensor unit, and / or an electrical current induced in the sensor unit, in particular in the sensor element of the sensor unit. An “interference signal” is to be understood in particular as an undesired signal which is superimposed on a main signal in particular and which in particular has an amount which is smaller than an amount of the main signal. The interference signal could, for example, be designed as noise, in particular as background noise and / or as signal noise, and / or as a scatter signal. In particular, the interference signal could be influenced and / or caused by coupling, in particular by inductive and / or capacitive and / or galvanic coupling, of the heating unit and the sensor unit. The interference signal has, in particular, a high frequency, which is in particular higher than a frequency of the main signal. In particular, the interference signal is proportional to a frequency of an electromagnetic alternating field provided by the heating unit and / or to a field strength of an electromagnetic flux provided by the heating unit. A “main signal” is to be understood in particular as a signal which is characterized in particular by at least one electrical parameter and which is embodied in particular as a useful signal. The electrical parameter could in particular be at least one electrical current and / or at least one electrical voltage and / or at least one frequency. The main signal has, in particular, a low frequency, which is in particular less than a frequency of the interference signal.

A signal “influenced by the heating unit” should be understood to mean, in particular, a signal which is dependent on at least one operating parameter of the heating unit influencing the signal. In particular, the signal influenced by the heating unit occurs exclusively in at least one activated state of the heating unit influencing the signal. The heating unit could, for example, influence the main signal of the signal. Alternatively or additionally, the heating unit could, for example, influence the interference signal superimposed on the main signal.

A “control unit” is to be understood in particular as an electronic unit which is preferably at least partially integrated in a control and / or regulating unit of a cooking appliance and which is preferably provided for at least the heating unit and / or to control and / or regulate the sensor unit. The control unit preferably comprises a computing unit and, in particular, in addition to the computing unit, a memory unit with a control and / or regulating program stored therein which is provided to be executed by the computing unit.

In particular, the control unit has at least one communication unit which is provided in particular for communication with the sensor unit, in particular with at least one communication unit of the sensor unit. In particular, the sensor unit has at least one communication unit which is provided in particular for communication with the control unit, in particular with the communication unit of the control unit. In at least one operating state, the sensor unit could in particular transmit the value characterizing the sensor parameter to the control unit, which could in particular determine the degree of activity of the heating unit from the value characterizing the sensor parameter transmitted by the sensor unit. For example, the communication unit of the control unit could have at least one analog-digital converter, which could in particular be provided to transfer the signal received from the sensor unit into an evaluable signal.

A “degree of activity” is to be understood in particular as a parameter which indicates whether the heating unit is in an activated state and / or in a deactivated state. An "activated" state of the heating unit is to be understood as meaning, in particular, a state in which a current conduction path to the heating unit is established and / or in which the heating unit supplies energy to at least one particular set up cooking utensil for the purpose of heating the cooking utensils and / or in which the Heating unit carries at least electrical current. A “deactivated” state of the heating unit is to be understood in particular as a state in which a current conduction path to the heating unit is interrupted and / or in which the heating unit is out of operation.

The degree of activity of the heating unit determined by the control unit is, in particular, the degree of activity of that heating unit which influences the interference signal, in particular regardless of which heating unit influences the main signal. For example, the main signal could be influenced by at least one further heating unit, which could in particular be different from the heating unit influencing the interference signal. Alternatively or additionally, the heating unit which influences the interference signal could in particular additionally influence the main signal.

The sensor element could, for example, be assigned to the heating unit which influences the signal and, in at least one operating state, the signal in particular in one Detected close range of the heating unit. Alternatively, the sensor element could, for example, be assigned to at least one further heating unit, which could in particular be different from the heating unit, and detect the signal in particular in a close range of the further heating unit.

“Provided” is to be understood in particular as specifically programmed, designed and / or equipped. The fact that an object is provided for a specific function is to be understood in particular to mean that the object fulfills and / or executes this specific function in at least one application and / or operating state.

It is further proposed that the sensor unit has at least one sensor element which is designed as a resistance sensor and is provided for the detection of the signal influenced by the heating unit. The sensor element could, for example, be a thermistor, which could in particular be referred to as an NTC resistor. The sensor element is advantageously a PTC thermistor, which is referred to in particular as a PTC resistor. In particular, the sensor element detects the signal influenced by the heating unit in at least one operating state. In particular, an inexpensive configuration and / or reliable detection of the signal can thereby be made possible.

It is also proposed that the heating unit be designed as an induction heating unit. An "induction heating unit" is to be understood in this context in particular as a unit which is provided to generate an electromagnetic alternating field, in particular with a frequency of 20 kHz to 100 kHz, which is in particular provided in at least one, in particular metallic, preferably ferromagnetic Cooking utensil base, in particular of a cooking utensil that has been set up, for example, to be converted into heat by eddy current induction and / or magnetic reversal effects. In this way, in particular, a high level of operating convenience can be achieved, in particular due to a short heating time for cooking utensils and / or due to optimal cooking results.

The sensor unit could detect the signal, in particular the main signal of the signal and the interference signal of the signal, for example, temporally in a range of a zero crossing of a mains voltage. The sensor unit is preferably provided to detect the signal over time in a range of a maximum value of a mains voltage. A "range of a maximum value" of a mains voltage is to be understood in particular as a time range which is temporally arranged around a maximum value of the mains voltage and at a point in time at which the mains voltage assumes the maximum value, a time interval of a maximum of 20%, in particular of maximum 15%, advantageous of a maximum of 10%, particularly advantageously of a maximum of 7% and preferably of a maximum of 5% of a period of the mains voltage. At a point in time at which the line voltage assumes the maximum value, the line voltage has, in particular, a maximum and / or highest amount. In this way, in particular, a maximization of the interference signal can be achieved, whereby in particular a precise conclusion about the degree of activity of the heating unit can be made possible.

It is further proposed that the sensor unit, when viewed perpendicularly onto a main plane of extent of the heating unit, is arranged at least partially, in particular at least to a large extent and advantageously completely, in a vicinity of a center point and / or center of gravity of the heating unit. A "main plane of extent" of an object is to be understood in particular as a plane which is parallel to a largest side surface of a smallest imaginary geometric cuboid, which just completely surrounds the object, and in particular runs through the center of the cuboid. "At least to a large extent" is to be understood as meaning in particular a proportion, in particular a mass proportion and / or volume proportion, of at least 70%, in particular of at least 80%, advantageously of at least 90% and preferably of at least 95%. A "near area" of a center point and / or center of gravity of an object is to be understood in particular as an area which, when viewed perpendicularly onto a main plane of extent of the object, is a maximum of 25%, in particular a maximum of 20%, from the center point and / or center of gravity of the object %, advantageously of a maximum of 15%, particularly advantageously of a maximum of 10%, preferably of a maximum of 7% and particularly preferably of a maximum of 5% of a total extent of the object in the main plane of extent of the object. The phrase that the sensor unit is arranged "at least partially" in a near area of a center point and / or center of gravity of the heating unit is to be understood in particular to mean that the sensor unit has at least one sensor element which is located in the near area of the center point and / or center of gravity of the heating unit is arranged, and could, for example, additionally have at least one further sensor element which is different from the sensor element and which in particular could be arranged outside the vicinity of the center point and / or center of gravity of the heating unit. As a result, the signal can in particular be detected very precisely. In particular, the signal can be detected directly on the heating unit, as a result of which, in particular, a transmission of the signal can be dispensed with and thus in particular a low probability of losses and / or errors can be enabled.

For example, from the interference signal superimposed on the main signal, the control unit could determine at least one inductance of the heating unit designed as an induction heating unit and / or at least a number of windings of at least one heating line of the heating unit designed as an induction heating unit and / or at least one electrical current and / or at least one electrical voltage. In particular, the control unit could determine at least one magnetic flux and / or at least a strength of a magnetic flux of an electromagnetic alternating field provided by the heating unit from the interference signal superimposed on the main signal. The control unit is preferably provided to determine at least one frequency from the interference signal superimposed on the main signal of the signal. In at least one operating state, the control unit could, for example, compare the value which is transmitted by the sensor unit and characterize the sensor parameter with at least one reference value and in particular determine the frequency directly from the comparison. In particular, the control unit could have at least one memory unit in which in particular at least one reference value could be stored, in particular in the form of at least one table and / or at least one function. Alternatively or additionally, in at least one operating state, the control unit could in particular transform a time curve of the Fourier value characterizing the sensor parameter transmitted by the sensor unit and in particular determine the frequency from the Fourier transform. In particular, in at least one operating state, the control unit could in particular Fourier transform the signal, in particular the interference signal and / or the main signal, and in particular determine the frequency from the Fourier transform, in particular from a maximum value of the Fourier transform. Alternatively or additionally, the control unit could determine the frequency in at least one operating state by means of at least one high-pass filter and / or by means of at least one low-pass filter. A particularly high level of operational reliability can in particular be achieved in this way.

It is also proposed that the control unit is provided to determine the degree of activity of the heating unit on the basis of the determined frequency. In particular, the control unit determines the degree of activity of the heating unit in at least one operating state on the basis of the determined frequency. In particular, the control unit checks in at least one operating state whether the determined frequency is located within an expected frequency range, which is particularly typical for a heating unit designed as an induction heating unit and which extends in particular from 20 kHz to 100 kHz. In the event that the determined frequency is arranged within the frequency range to be expected, the control unit concludes in at least one operating state that the heating unit is in an activated state. In the event that the determined frequency is outside of the frequency range to be expected is arranged, the control unit initiates in at least one operating state in particular at least one further action, in particular at least one further check. As a result, the degree of activity of the heating unit can in particular be reliably determined, specifically in particular on the basis of a parameter that optimally characterizes an activity of the heating unit.

It is further proposed that the control unit is provided to compare the determined degree of activity of the heating unit with an expected degree of activity of the heating unit and to initiate at least one safety measure in the event of a deviation. The safety measure could, for example, be outputting at least one warning, in particular to an operator. Alternatively or additionally, the safety measure could in particular be a deactivation of at least one heating unit, in particular the heating unit. In at least one operating state, the control unit checks in particular whether the sensor element which is assigned to the heating unit has detected the determined frequency. If the determined frequency is detected by the sensor element which is assigned to the heating unit, the control unit concludes in at least one operating state, in particular, that the heating unit is in an activated state. In at least one operating state, the control unit compares in particular the determined frequency, which in particular the sensor element assigned to the heating unit has detected, with an expected frequency of the heating unit by means of which the heating unit is operated in particular. If the determined frequency and the expected frequency match, the control unit concludes that there is a proper operating state in which, in particular, a switch position of at least one switch unit is correct and / or error-free. If the determined frequency is detected by at least one further sensor element which is assigned to at least one further heating unit different from the heating unit, the control unit concludes in at least one operating state in particular that the heating unit is in an activated state, although this heating unit is in particular in should be in a disabled state. In at least one operating state, the control unit compares in particular the determined frequency, which in particular the sensor element assigned to the heating unit has detected, with an expected frequency of the heating unit by means of which the heating unit is operated in particular. In the event of a discrepancy between the determined frequency and the expected frequency, the control unit concludes that there is a faulty operating state in which, in particular, a switching position of at least one switching unit is faulty. In this way, in particular, a high security standard can be guaranteed.

In at least one operating state, the control unit could, for example, only evaluate the interference signal and, in particular, ignore and / or ignore the main signal. The control unit is preferably provided to determine at least one property of the heating unit that differs from a degree of activity from the main signal of the signal. A “property different from a degree of activity” of the heating unit is to be understood as meaning, in particular, a property of the heating unit which goes beyond a determination of an activated state of the heating unit and a deactivated state of the heating unit. As a result, in particular at least one further sensor unit, which could be provided in particular for detecting the property of the heating unit that differs from a degree of activity, can be dispensed with, which in particular enables low costs and / or low storage. In particular, a high level of information can be extracted from the signal, which in particular enables a high level of operational reliability.

The property of the heating unit that differs from a degree of activity could, for example, be a magnetic flux provided by the heating unit and / or an inductance of the heating unit designed as an induction heating unit and / or at least a number of windings of at least one heating line of the heating unit designed as an induction heating unit and / or at least one electric current and / or at least be an electrical voltage. The property of the heating unit which differs from a degree of activity is preferably a temperature of the heating unit. On the basis of the temperature, which the control unit determines in particular from the main signal of the signal, the control unit determines, in at least one operating state, in particular a degree of activity of the heating unit. In particular, in at least one operating state, the control unit compares the level of activity which the control unit determines, in particular based on the interference signal, and the level of activity which the control unit determines, in particular based on the main signal of the signal. If the level of activity, which the control unit determines based on the interference signal, and the level of activity, which the control unit determines based on the main signal of the signal, match, the control unit concludes, in at least one operating state, that the operating state is correct, in which in particular one switching position is at least of a switching unit is correct and / or error-free. In the event of a discrepancy between the level of activity, which the control unit determines based on the interference signal, and the level of activity, which the control unit determines based on the main signal of the signal, the control unit concludes, in at least one operating state, that there is a faulty operating state, in which in particular one switching position is at least a switching unit is faulty, and in particular initiates at least one safety measure. In at least In an operating state, the control unit could, for example, execute at least one automatic cooking process as a function of the temperature of the heating unit. Alternatively or additionally, depending on the temperature of the heating unit, the control unit could protect the heating unit from overheating in at least one operating state and, in particular, initiate at least one safety measure in the case in which the temperature of the heating unit is greater than a maximum temperature of the heating unit. The maximum temperature of the heating unit could in particular be a maximum temperature at which the heating unit can be operated safely. In this way, in particular, a particularly high level of operational reliability can be achieved. In particular, an optimal safety standard can be provided, since in particular the determined degree of activity can be checked and / or overheating of the heating unit can be avoided.

According to the invention, the cooking appliance device has at least one switching unit, which is provided to establish and interrupt at least one current path to the heating unit, the control unit being provided to check a function of the switching unit on the basis of the interference signal. In particular, the control unit concludes that the switching unit is functioning properly and / or that the operating state is correct if the degree of activity of the heating unit determined on the basis of the interference signal corresponds to at least one expected degree of activity of the heating unit and / or to at least one of the degree of activity determined on the basis of the main signal Activity level of the heating unit. In at least one operating state, the control unit draws attention to a faulty function of the switching unit and / or to a faulty operating state in the event of a discrepancy between the level of activity of the heating unit determined on the basis of the interference signal and at least one expected level of activity of the heating unit and / or from at least one of the Level of activity of the heating unit determined on the basis of the main signal. If the activity level of the heating unit determined on the basis of the interference signal deviates from at least one expected activity level of the heating unit and / or from at least one of the activity level of the heating unit determined on the basis of the main signal, the control unit initiates at least one safety measure, in particular in at least one operating state. A “switching unit” is to be understood in particular as a unit with at least one switching element which is provided to change a current conducting property and / or at least one current conducting path when a switching position of the switching element changes. The switching unit has in particular at least two, in particular at least three, advantageously at least four, particularly advantageously at least six, preferably at least ten and particularly preferably a plurality of switching elements. In particular, at least two switching elements of the switching unit are connected next to one another. In particular, there are at least two switching elements of the switching unit connected in series. The switching elements of the switching unit form in particular at least one switching matrix. In at least one operating state, the switching unit is arranged in particular between the supply unit and the heating unit and / or the further heating unit. In particular, a line path, which in at least one operating state connects the supply unit to the heating unit and / or to the further heating unit, leads via the switching unit. The switching unit is provided in particular to establish and / or interrupt a conduction path between the supply unit and the heating unit and / or the further heating unit in at least one operating state. In this way, in particular an operating state that is potentially dangerous for an operator, in which the heating unit in particular is in a degree of activity different from an expected degree of activity, can be avoided, whereby a high safety standard can be made possible. The switching unit can in particular achieve a high degree of flexibility, since an operator can in particular be offered the option of activating different heating zones, in particular at low costs for electronics, in particular for cooking appliance electronics.

A particularly high level of operational reliability can in particular be achieved by a cooking appliance, in particular by an induction cooking appliance and advantageously by an induction hob, with at least one cooking appliance device.

The cooking appliance device is not intended to be restricted to the application and embodiment described above. In particular, the cooking appliance device can have a number of individual elements, components and units that differs from a number of individual elements, components and units mentioned herein in order to fulfill a mode of operation described herein.

Further advantages emerge from the following description of the drawings. Exemplary embodiments of the invention are shown in the drawing. The drawing, the description and the claims contain numerous features in combination.

Fig. 1

ein Gargerät mit einer Gargerätevorrichtung in einer schematischen Draufsicht,

Fig. 2

eine Versorgungseinheit, eine Schalteinheit, eine Heizeinheit und drei weitere Heizeinheiten der Gargerätevorrichtung in einer schematischen Darstellung,

Fig. 3

ein Diagramm mit einem oberen Teildiagramm, in welchem eine Netzspannung über einer Zeit aufgetragen ist, und mit einem unteren Teildiagramm, in welchem ein Heizstrom über einer Zeit aufgetragen ist, in einer schematischen Darstellung,

Fig. 4

ein Diagramm, in welchem eine Sensorspannung in Abhängigkeit von einer Zeit aufgetragen ist, in einer schematischen Darstellung und

Fig. 5

ein Diagramm, in welchem eine Fourier-Transformierte der Sensorspannung aus Fig. 4 aufgetragen ist, in einer schematischen Darstellung.

Show it:

Fig. 1

a cooking appliance with a cooking appliance device in a schematic top view,

Fig. 2

a supply unit, a switching unit, a heating unit and three further heating units of the cooking appliance device in a schematic representation,

Fig. 3

a diagram with an upper partial diagram in which a network voltage is plotted over time, and with a lower partial diagram in which a heating current is plotted over time, in a schematic representation,

Fig. 4

a diagram in which a sensor voltage is plotted as a function of time, in a schematic representation and

Fig. 5

a diagram in which a Fourier transform of the sensor voltage from Fig. 4 is applied, in a schematic representation.

Fig. 1 shows a cooking device 28 which is designed as an induction cooking device. In the present exemplary embodiment, the cooking appliance 28 is designed as an induction hob. The cooking appliance 28 has a cooking appliance device 10 which is designed as an induction cooking appliance device. In the present exemplary embodiment, the cooking appliance device 10 is designed as an induction hob device.

The cooking appliance device 10 has an appliance plate 30. In the present exemplary embodiment, the device plate 30 is designed as a hob plate. In an assembled state, the device plate 30 forms part of an outer device housing, in particular an outer device housing, in particular of the cooking device 28. The device plate 30 is provided for setting up cooking utensils (not shown).

The cooking appliance device 10 has a user interface 32 for inputting and / or selecting operating parameters, for example a heating power and / or a heating power density and / or a heating zone. The operator interface 32 is provided for outputting a value of an operating parameter to an operator.

The cooking appliance device 10 has a heating unit 12. In addition to the heating unit 12, the cooking appliance device 10 has a large number of further heating units 34. In the figures, only one object of multiple existing objects is provided with a reference symbol. In the present exemplary embodiment, the cooking appliance device 10 has thirty-five further heating units 34 in addition to the heating unit 12. The heating unit 12 and the further heating units 34 are arranged in an installation position below the device plate 30. The heating unit 12 and the further heating units 34 are provided to heat cookware placed on the appliance plate 30 above the heating unit 12 and / or the further heating units 34.

The heating unit 12 is designed as an induction heating unit. The further heating units 34 are each designed as an induction heating unit. Heat in one operating state Cooking utensils placed on the heating units 12, 34 inductively, in particular by means of an electromagnetic alternating field provided by the corresponding heating unit 12, 34.

The cooking appliance device 10 has a sensor unit 14. The sensor unit 14 has a multiplicity of sensor elements 18. In the present exemplary embodiment, the sensor unit 14 has thirty-six sensor elements 18. The sensor unit 14 has one sensor element 18 per heating unit 12, 34. In each case one sensor element 18 is assigned to one of the heating units 12, 34.

In the following, the sensor element 18, which is assigned to the heating unit 12, is described without loss of generality. An analogous description could be given for each sensor element 18 and that heating unit 12, 34 to which the corresponding sensor element 18 is assigned.

When viewing a main plane of extent of the heating unit 12 at right angles, the sensor element 18, which is assigned in particular to the heating unit 12, is arranged in a close range of a center point and / or center of gravity 24 of the heating unit 12. When viewed perpendicularly, a main plane of extent of the heating unit 12 is partially arranged in the vicinity of a center point and / or center of gravity 24 of the heating unit 12, in particular in the form of the sensor element 18, which is assigned in particular to the heating unit 12.

In an operating state, the sensor unit 14 detects a signal influenced by the heating unit 12, in particular by means of the sensor element 18. The sensor unit 14 is provided for detecting at least one signal influenced by the heating unit 12. In an operating state, the heating unit 12 produces a main signal of the signal and an interference signal of the signal in the sensor element 18. In an operating state, the heating unit 12 in the sensor element 18 produces the main signal of the signal on the basis of heating energy provided by the heating unit 12 in an operating state. In an operating state, the heating unit 12 causes the interference signal of the signal in the sensor element 18 on the basis of an electromagnetic alternating field provided by the heating unit 12 in an operating state.

The cooking appliance device 10 has a control unit 16. The control unit 16 is provided to carry out actions and / or to change settings as a function of operating parameters entered by means of the operator interface 32. The control unit 16 regulates an energy supply to the heating units 12, 34 in a heating operating state.

The cooking appliance device 10 has a supply unit 36 (cf. Fig. 2 ). In one operating state, the supply unit 36 supplies the heating units 12, 34 with heating energy.

The supply unit 36 has several inverters 38, of which only two are shown in the figures. A number of inverters 38 is smaller than a number of heating units 12, 34. In one operating state, control unit 16 controls supply unit 36. The control unit 16 operates the heating units 12, 34 in an operating state by means of the supply unit 36.

The cooking appliance device 10 has a switching unit 26. The switching unit 26 is arranged electrically between the supply unit 36 and the heating units 12, 34. In one operating state, the switching unit 26 establishes a current path to the corresponding heating unit 12, 34. Alternatively or additionally, the switching unit 26 interrupts a current path to the corresponding heating unit 12, 34 in an operating state.

The switching unit 26 has a multiplicity of switching elements 40. The switching elements 40 are arranged in a switching matrix. Only six of the switching elements 40 are shown in the figures.

In an operating state, the sensor unit 14 detects the signal influenced by the heating unit 12, in particular by means of the sensor element 18. The sensor element 18 is provided for the detection of the signal influenced by the heating unit 12. In the present exemplary embodiment, the sensor element 18 is designed as a resistance sensor. In the present exemplary embodiment, the sensor element 18 is designed as an NTC resistor.

In an operating state, in particular by means of the sensor element 18, the sensor unit 14 detects a main signal of the signal and an interference signal of the signal superimposed on the main signal (cf. Fig. 4 ). In order to maximize the signal strength of the interference signal, the sensor unit 14 detects the signal in an operating state over time in a range of a maximum value 20 of a mains voltage 22 (cf. Fig. 3 ).

Fig. 3 shows a diagram with two partial diagrams. In an upper partial diagram, the line voltage 22 is plotted over time. The line voltage 22 is plotted on an ordinate axis 42. A time is plotted on an abscissa axis 44. In Fig. 3 two rectified half-waves of the line voltage 22 and thus in particular an entire period of the rectified line voltage 22 are shown. A heating current is plotted over time in a lower partial diagram. A heating current is plotted on an ordinate axis 46. A time is plotted on an axis of abscissa 48. In each of the two partial diagrams, the area in which the sensor unit 14 detects the signal in an operating state is highlighted.

The sensor unit 14 transmits the detected signal to the control unit 16 in an operating state. The control unit 16 evaluates the signal transmitted by the sensor unit 14 in an operating state. The sensor unit 14 also transmits to the control unit 16 in an operating state, in particular in connection with the signal, which sensor element 18 has detected the signal.

In an operating state, the control unit 16 determines a degree of activity of the heating unit 12 from an interference signal superimposed on a main signal of the signal. To determine the degree of activity of the heating unit 12, the control unit 16 in an operating state determines a frequency 64 of the heating unit 12 from the interference signal superimposed on the main signal of the signal In an operating state, the control unit 16 determines, from the signal detected by the sensor unit 14, a curve 50 of a sensor voltage which, in particular, drops at the sensor element 18 in the operating state, as a function of time (cf. Fig. 4 ).

Fig. 4 shows a diagram in which the curve 50 of the sensor voltage is shown as a function of time. The sensor voltage is plotted on an ordinate axis 54. A time is plotted on an abscissa axis 56. A main signal can be seen, which is essentially constant over time. A high-frequency interference signal is superimposed on the main signal.

From the curve 50 of the sensor voltage as a function of time, the control unit 16 determines a further curve 52 in an operating state, which is a Fourier transform of the curve 50 of the sensor voltage as a function of time (cf.

Fig. 5 ). In the present exemplary embodiment, the further course 52 is a fast Fourier transform of the course 50 of the sensor voltage as a function of time. The fast Fourier transform is known in particular by the abbreviation FFT. From the further curve 52, the control unit 16 determines the frequency 64 of the heating unit 12 in an operating state.

The control unit 16 determines the frequency 64 of the heating unit 12 from a maximum value 62 of the further course. In the present exemplary embodiment, the maximum value 62 is located at a frequency 64 of essentially 32 kHz.

On the basis of the determined frequency 64 of the heating unit 12, the control unit 16 determines the degree of activity of the heating unit 12 in an operating state. In the present exemplary embodiment, in which the frequency 64 of the heating unit 12 assumes a value of essentially 32 kHz, the control unit 16 determines in an operating state as Activity level the heating unit 12 has an activated state in which the heating unit 12 is in operation, in particular with the determined frequency 64 of the heating unit 12.

In one operating state, the control unit 16 compares the determined degree of activity of the heating unit 12 with an expected degree of activity of the heating unit 12. The control unit 16 checks whether the sensor element 18 which detects the signal is assigned to the heating unit 12. In the present case it was assumed that the sensor element 18 is assigned to the heating unit 12. In an operating state, the control unit 16 checks whether the determined frequency 64 of the heating unit 12 corresponds to an expected frequency of the heating unit 12, with which the control unit 16 operates, in particular, the heating unit 12.

In the event of a deviation, in particular the determined degree of activity of the heating unit 12 from the expected degree of activity of the heating unit 12 and / or the determined frequency 64 of the heating unit 12 from the expected frequency of the heating unit 12, the control unit 16 initiates at least one safety measure in an operating state . In the present exemplary embodiment, the safety measure is outputting a warning to an operator by means of the operator interface 32.

In an operating state, the control unit 16 deactivates the heating unit 12 in the event of a deviation, in particular the determined degree of activity of the heating unit 12 from the expected degree of activity of the heating unit 12 and / or the determined frequency 64 of the heating unit 12 from the expected frequency of the heating unit 12. The A safety measure is to deactivate the heating unit 12.

Using the interference signal, the control unit 16 checks a function of the switching unit 26 in an operating state. In the case of a match between the determined activity level of the heating unit 12 and the expected activity level of the heating unit 12 and / or the determined frequency 64 of the heating unit 12 and the expected frequency of the Heating unit 12 closes the control unit 16 to a proper function of the switching unit 26. In the event of a deviation, in particular the determined degree of activity of the heating unit 12 from the expected degree of activity of the heating unit 12 and / or the determined frequency 64 of the heating unit 12 from the expected frequency of the Heating unit 12, the control unit 16 detects a faulty function of the switching unit 26 in an operating state. The control unit 16 initiates at least one safety measure in the event of a deviation.

It is assumed below that the sensor element 18, which detects the signal, is assigned to the further heating unit 34, which in particular is different from the heating unit 12. The determined degree of activity of the heating unit 12, which the control unit 16 in an operating state from the interference signal superimposed on the main signal of the signal determined, is an activated state in which the heating unit 12 is in operation, in particular with the determined frequency 64 of the heating unit 12.

In the event of a deviation, in particular the determined degree of activity of the heating unit 12 from the expected degree of activity of the heating unit 12 and / or the determined frequency 64 of the heating unit 12 from the expected frequency of the heating unit 12, the control unit 16 compares the determined degree of activity of the heating unit 12 an expected degree of activity of the further heating unit 34 to which the sensor element 18 which detects the signal is assigned.

In the event of a discrepancy, in particular the determined degree of activity of the heating unit 12 from the expected degree of activity of the further heating unit 34 and / or the determined frequency 64 of the heating unit 12 from an expected frequency of the further heating unit 34, the control unit 16 concludes that the function is faulty Switching unit 26. The control unit 16 initiates at least one safety measure in the event of a deviation.

In a method for operating the cooking appliance device 10, a degree of activity of the heating unit 12 is determined in an operating state from an interference signal superimposed on a main signal of the signal. In the method for operating the cooking appliance device 10 in an operating state, a property of the heating unit 12 that differs from a degree of activity is determined from the main signal.

The control unit 16 determines in an operating state from the main signal the property of the heating unit 12 that differs from the degree of activity. The property of the heating unit 12 different from the degree of activity is a temperature of the heating unit 12. In an operating state, the control unit 16 determines the property of the heating unit 12 which differs from the degree of activity Heating unit 12 from curve 50 of the sensor voltage as a function of time.

REFERENCE MARK

10

Cooking device device

12th

Heating unit

14th

Sensor unit

16

Control unit

18th

Sensor element

20th

Maximum value

22nd

Mains voltage

24

Center point and / or focus

26th

Switching unit

28

Cooking appliance

30th

Device plate

32

Operator interface

34

Another heating unit

36

Supply unit

38

Inverter

40

Switching element

42

Ordinate axis

44

Abscissa axis

46

Ordinate axis

48

Abscissa axis

50

course

52

Further course

54

Ordinate axis

56

Abscissa axis

58

Ordinate axis

60

Abscissa axis

62

Maximum value

64

frequency

Claims (11)

1. Cooking appliance device, in particular induction hob device, having at least one heating unit (12), having at least one sensor unit (14), which is provided to detect at least one signal influenced by the heating unit (12), and having at least one control unit (16), which is provided to determine at least one level of activity of the heating unit (12) from an interference signal overlaying a main signal of the signal, characterised by at least one switching unit (26), which is provided to establish at least one flow path to the heating unit (12) and to interrupt the same, wherein the control unit (16) is provided to check a function of the switching unit (26) on the basis of the interference signal.
2. Cooking appliance device according to claim 1, characterised in that the sensor unit (14) has at least one sensor element (18), which is embodied as a resistance sensor and is provided to detect the signal influenced by the heating unit (12).
3. Cooking appliance device according to claim 1 or 2, characterised in that the heating unit (12) is embodied as an induction heating unit.
4. Cooking appliance device according to one of the preceding claims, characterised in that the sensor unit (14) is provided to detect the signal temporally in a region of a maximum value (20) of a mains voltage (22).
5. Cooking appliance device according to one of the preceding claims, characterised in that when observed at right angles onto a main extension plane of the heating unit (12), the sensor unit (14) is arranged at least partially in a close range of a centre point and/or centre of gravity (24) of the heating unit (12).
6. Cooking appliance device according to one of the preceding claims, characterised in that the control unit (16) is provided to determine at least one frequency (64) from the interference signal overlaying the main signal of the signal.
7. Cooking appliance device according to claim 6, characterised in that the control unit (16) is provided to determine the level of activity of the heating unit (12) on the basis of the determined frequency (64).
8. Cooking appliance device according to one of the preceding claims, characterised in that the control unit (16) is provided to compare the determined level of activity of the heating unit (12) with a level of activity of the heating unit (12) to be expected, and in the case of a variation, to introduce at least one safety measure.
9. Cooking appliance device according to one of the preceding claims, characterised in that the control unit (16) is provided to determine at least one property of the heating unit (12), which differs from a level of activity, from the main signal of the signal.
10. Cooking appliance device according to claim 9, characterised in that the property of the heating unit (12) which differs from a level of activity is a temperature of the heating unit (12).
11. Cooking appliance, in particular induction hob, having at least one cooking appliance device (10) according to one of the preceding claims.

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