Cooking hob, combination appliance and method for controlling a cooking hob or a combination appliance

Abstract

The present invention relates to a cooking hob, a combination appliance and a method for controlling a cooking hob or a combination appliance. The cooking hob comprises or is connected to at least one wall or panel, an acceleration detection and / or measuring means configured to detect an acceleration of a section or a reference point of the wall or the panel of the cooking hob, and a control unit for controlling operating processes. The acceleration detection and / or measuring means is connected to the control unit for exchange of data. The acceleration detection and / or measuring means forms a trigger element for the control unit and is configured to provide a trigger signal for a control of a function and / or an operating process in the cooking hob. The cooking hob further comprises or is connected to an extraction device, which is configured to suck in cooking vapours arising on at least one cooking zone of the cooking hob as a result of a cooking process. The control unit is adapted to control the function and / or operating process in the cooking hob based on the trigger signal of the acceleration detection and / or measuring means during a parallel operation of the cooking hob and the extraction device.

Description

[0001] Description

[0002] Cooking hob, combination appliance and method for controlling a cooking hob or a combination appliance

[0003] The present invention relates to a cooking hob, comprising or being connected to at least one wall or panel , and further comprising an acceleration detection and / or measuring means , and a control unit . The present invention further relates to a combination appliance and a method for controlling a cooking hob .

[0004] From EP 2 999 301 Al an induction cooking hob with a boiling detection and an induction energy control is known . Vibrations caused by bubbles forming inside of a heated substance can be detected based on information of a micro-electromechanical system processing signals from an acceleration sensor in combination with a temperature sensor associated to a heating zone . The cooking process is controlled from the start by a control unit of the induction cooking hob and a user has to start the automated process with the boiling detection function by pressing a dedicated button .

[0005] It is an obj ect of the present invention to extend the area of automation in the technical field of cooking appliances during performance of cooking processes . More speci fically, automation of cooking processes by making use of acceleration data shall be considered for an increased area of application in the field of cooking appliances .

[0006] The obj ect is achieved by a cooking hob according to one aspect of the invention . According to a first aspect of the invention, a cooking hob comprises or is connected to at least one wall or panel , and further comprises an acceleration detection and / or measuring means configured to detect an acceleration of a section or a reference point of the wall or the panel of the cooking hob, and a control unit for controlling operating processes . The at least one wall or panel is in particular a cooktop or cooking surface of the cooking hob . The acceleration detection and / or measuring means may be an acceleration sensor, which particularly comprises a microelectromechanical systems device . The acceleration detection and / or measuring means is connected to the control unit for an exchange of data . Moreover, the acceleration detection and / or measuring means forms a trigger element for the control unit and is configured to provide a trigger signal for a control of a function and / or an operating process in the cooking hob . According to the present invention, the cooking hob further comprises or is connected to an extraction device , which is configured to suck in cooking vapours arising on at least one cooking zone of the cooking hob as a result of a cooking process . The connection of the extraction device to the cooking hob is in particular reali zed by a physical attachment or a connection in a sound-conducting manner . The cooking hob and the extraction device particularly form a combination appliance . The control unit is adapted to control the function and / or operating process in the cooking hob based on the trigger signal of the acceleration detection and / or measuring means during a parallel operation of the cooking hob and the extraction device .

[0007] Due to the fact , that the function and / or operating process in the cooking hob is controllable by the control unit based on the trigger signal of the acceleration detection and / or measuring means during a parallel operation of the cooking hob and an ex- traction device assigned to the cooking hob in a sound-conducting manner, an automation of cooking processes by making use of acceleration data is extended to this kind of cooking hobs , which include or which are connected to an extraction device , as it is for example the case in a combination appliance that comprises said two appliances . The inventors of the present invention have surprisingly found that this automated control of cooking processes by using an acceleration detection and / or measuring means also works in and can be extended to this increased area of application in the field of cooking appliances .

[0008] According to a preferred embodiment , when the cooking hob is in an installation position, the extraction device is arranged below the cooking hob, preferably attached to a bottom side of the cooking hob . Moreover, an extraction opening is arranged in the cooktop or cooking surface , which forms an upper wall or panel of the cooking hob and which includes the at least one cooking zone of the cooking hob . Preferably, the extraction opening is arranged in a central position of a cooktop or cooking surface . The acceleration detection and / or measuring means is arranged on or at the cooktop or cooking surface , preferably on a bottom side of the cooktop or cooking surface , when the cooking hob is in said installation position . The arrangement of the acceleration detection and / or measuring means is performed in close distance to the extraction opening, preferably close to a peripheral edge of the extraction opening . Additionally, or alternatively, the arrangement of the acceleration detection and / or measuring means is performed distant from the control unit and / or from a user interface of the cooking hob adapted to receive operational instructions from a user of the appliance and / or to provide information to the user . In particular, the acceleration detection and / or measuring means is arranged on a rear side of a peripheral edge of the extraction opening, when the cooking hob is in said installation position . With such particular arrangement , speci fically close to a peripheral edge of the extraction opening, the acceleration signals sourcing from any one of the cooking zones positioned on the cooktop or cooking surface can be detected and / or measured by the acceleration detection and / or measuring means . Moreover, the more speci fic positioning of the acceleration detection and / or measuring means distant from the control unit and / or from the user interface reduces any interfering acceleration signal that may arise from the operation of these devices notably with the frequency of the mains .

[0009] The acceleration detection and / or measuring means may be a single-unit solution, i . e . only one acceleration detection and / or measuring element may be used for a detection and / or measurement of a signal sourcing from any one of a plurality of cooking zones . As an alternative to the provision of only one such unit , more than only one acceleration detection and / or measuring element may be arranged in the cooking hob, in particular each one of the plurality of cooking zones may receive an acceleration detection and / or measuring element speci fically assigned to this cooking zone . With such a "one-for-one" provision, particularly exact signal detection and / or measurement is possible .

[0010] In some implementations , the acceleration detection and / or measuring means is configured to provide a trigger signal based on a cooking process performed on one of at least a first cooking zone and a second cooking zone . Preferably, the cooking hob comprises a plurality of cooking zones , and the cooking process may be performed on one of said plurality of cooking zones , which are distributed over the surface of the cooktop or cooking surface . In that case , the trigger signal may be based on a cooking process performed on one of said plurality of cooking zones . The identi fication of the respective cooking zone is performed by at least one of at least a first and a second acceleration detection and / or measuring sensor, at least one acceleration detection and / or measuring sensor and at least an additional optical and / or temperature sensor, a detection or readout of power settings and / or current operating times of or related to the at least first cooking zone and second cooking zone , and a detection means configured to evaluate the distance of the source of the acceleration to the acceleration detection and / or measuring means and / or the direction of the acceleration .

[0011] In a preferred embodiment , the acceleration detection and / or measuring means is adapted to recogni ze and / or to evaluate vibrations originating from speci fic operating conditions . Said speci fic operating conditions particularly comprise a boiling of a fluid included in a cookware placed on the cooking zone . Further, the control unit may be adapted to control the function and / or operating process in the cooking hob based on the recogni zed and / or evaluated vibrations .

[0012] According to embodiments , the cooking hob includes a filter means configured to suppress or filter out vibration noise caused by the operation of the extraction device and received by the acceleration detection and / or measuring means . More speci fically, said filter means are included in or assigned to the acceleration detection and / or measuring means or the control unit of the cooking hob .

[0013] Favourably, the control unit is configured to control the function and / or operating process in the cooking hob after reaching or exceeding a predefined signal threshold . Said predefined signal threshold may indicate to the control unit that a particular operating condition, notably starting of a boiling of the fluid, occurs or has occurred, which event will then be a trigger for the control unit to initiate the control of the speci fic function and / or an operating process in the cooking hob .

[0014] A speci fically preferred embodiment is characteri zed in that said predefined signal threshold is based on or includes a factor x of a current vibration value detected and / or measured at a particular time during the cooking process in relation to an initial vibration value detected and / or measured at an initial point in time or an initial period of time of the cooking process . The initial vibration value is preferably based on, particularly calculated from, an averaging of continuous or discrete initial vibration values detected and / or measured during a time interval at the beginning of the cooking process .

[0015] In some implementations , the extraction device is operable in at least a first operating mode and a second operating mode . This may be provided by an operability of the extraction device with at least a first speed and a second speed of a ventilation means of the extraction device . In that case , the acceleration detection and / or measuring means is configured for a control of the function and / or operating process in the cooking hob based on or as a result of or in consideration of the influence of an acceleration detection and / or measuring during each one of the first operating mode and the second operating mode of the extraction device . It is noted that particularly the di f ferent speed levels may cause di f ferent vibration types , e . g . di f ferent vibration frequencies , with di f ferent influences on the acceleration detected and / or measured by the acceleration detection and / or measuring means . According to a particularly preferred embodiment, the factor x of said current vibration value in relation to said initial vibration value is dependent on the current operating mode of the extraction device. This may be defined in that way that a first factor Xx is assigned to the first operating mode, e. g. the first speed of the ventilation means, and a second factor x2is assigned to the second operating mode, e. g. the second speed of the ventilation means, of the extraction device. It may be further provided, that the control unit preferably includes or relies on a database comprising an assignment table that relates factors x, i.e. x2, x2, ... xn, to fan speeds.

[0016] A specific embodiment is characterized in that the control unit includes an algorithm, which comprises a transformation of signals from time domain to frequency domain. Said transformation preferably includes a Fourier transformation algorithm. With such specific technique, the individual frequencies sourcing from different components of the cooking hob and / or the related extraction device, may be separated from each other.

[0017] Further, it is favourable to provide for a control unit that includes an algorithm, which comprises a negative feedback compensation. Such technique preferably performs or contributes to a neutralization of vibration noise, which is caused by the operation of the extraction device and is received by the acceleration detection and / or measuring means.

[0018] The object is achieved by a combination appliance including a cooking hob and an extraction device according to another aspect of the invention. A combination appliance includes the cooking hob as herein disclosed, more speci fically a cooking hob as previously described, and an extraction device . The extraction device comprises a ventilation means and is configured to suck in cooking vapours arising on at least one cooking zone of the cooking hob .

[0019] Finally, the obj ect is achieved by a method for controlling a cooking hob or a combination appliance with a cooking hob according to a further aspect of the invention .

[0020] According to a further aspect of the invention, a method for controlling a cooking hob or a combination appliance with a cooking hob is disclosed . The cooking hob comprises at least one wall or panel , an acceleration detection and / or measuring means , and a control unit for controlling operating processes . The at least one wall or panel may be a cooktop or cooking surface . Further, the acceleration detection and / or measuring means may be an acceleration sensor, particularly comprising a microelectromechanical systems device . According to this further aspect of the invention, the acceleration detection and / or measuring means detects and / or measures an acceleration signal of a section or a reference point of the wall or panel of the cooking hob . The acceleration signal bases on a superposition of a first vibration signal and a second vibration signal , wherein the first vibration signal originates from a cooking process performed on the cooking hob and the second vibration signal originates from an operation of an extraction device . Said extraction device is comprised in or is connected to the cooking hob, and it may be configured to suck in cooking vapours arising on at least one cooking zone of the cooking hob as a result of a cooking process . The connection of the extraction device and the cooking hob may be reali zed by a physical attachment or connection in a sound-conducting manner . In particular, the cooking hob and the extraction device form a combination appliance . Moreover, the inventive method provides that a function and / or an operating process in or of the cooking hob is triggered as a result of the detected and / or measured acceleration signal .

[0021] A speci fic embodiment of the method is characteri zed in that the acceleration detection and / or measuring means recogni zes and / or evaluates a vibration signal originating from a boiling of a fluid included in a cookware placed on a cooking zone of the cooking hob . Based on a particular boiling condition of the fluid, the control unit controls the function and / or the operating process in or of the cooking hob . More speci fically, the recogni zed and / or evaluated vibration signal forms the first vibration signal .

[0022] The influence of the second vibration signal may be neutrali zed by making use of at least one of the techniques trans formation of the acceleration signal from time domain to frequency domain, which trans formation preferably includes a Fourier trans formation algorithm, and negative feedback compensation .

[0023] According to a particularly preferred embodiment of the method, a boiling condition of the fluid is identi fied during the run of an algorithm, which includes the steps of trans formation of the acceleration signal from time domain to frequency domain, identi fying the frequencies originating from the extraction device , neutrali zing the extraction device frequencies by a negative feedback compensation, preferably removing signals in a frequency range originating from components , in particular from electronic components , operated in the mains frequency or a multiple of the mains frequency .

[0024] Preferably, during the phase from starting the cooking process until identi fication of the boiling of the fluid, the operating conditions of the extraction device is kept constant . More speci fically, a speed of a ventilation means of the extraction device is kept constant until the event of boiling is identi fied . With such constant operating conditions of the extraction device , the influence of this device is kept unchanged, so that the ef fect of the second vibration signal sourcing from the operated extraction device is not altered, which facilitates the compensation and / or neutrali zation of the related vibration frequencies and keeps a respective computing ef fort of the control unit comparably low .

[0025] Novel and inventive features of the present invention are set forth in the appended claims .

[0026] The present invention will be described in further detail with reference to the drawings , in which

[0027] Fig . 1 is a perspective view of a combination appliance comprising a cooking hob and a downdraft extraction device installed in a kitchen cabinet ;

[0028] Fig . 2 is a cross-sectional perspective view of the disassembled combination appliance of Fig . 1 with a frontal surface cut away and including a removable filter device ; Fig . 3 is a top perspective view of the combination appliance according to Figs . 1 and 2 , with a removed cooktop for better illustrating a first example for the positioning of a vibration sensor ;

[0029] Fig . 4 is a bottom view of the cooktop removed from the combination appliance of Fig . 3 , but with a second example for the positioning of the vibration sensor ;

[0030] Fig . 5 is a diagram illustrating an "acceleration a over time t" related to a first rotational speed of a fan of the extraction device , wherein the illustrated function is the result of an algorithm for elimination of the influence of noise signals from the AC mains power ;

[0031] Fig . 6 is a diagram illustrating a "processed acceleration apover time" for the first fan speed level , with the function of Fig . 5 having been processed by Fourier transformation with removing and neutrali zing speci fic frequencies sourcing from the operation of the extraction fan of the combination appliance ; and

[0032] Fig . 7 is a diagram illustrating a "processed acceleration apover time t" related to a second rotational speed of the extraction fan of the extraction device .

[0033] In all figures the same or equivalent part are marked with the same reference numbers .

[0034] Fig . 1 illustrates a general setup of a standard combination appliance 10 comprising a cooking hob 12 and a downdraft extraction device 14 installed in a kitchen cabinet 16 . The cooking hob 12 is implemented in a cut-out of a kitchen countertop 18 forming a top cover plate of the kitchen cabinet 16 . The downdraft extraction device 14 is configured to take away cooking vapours occurring during cooking processes , in particular when cooking with uncovered cookware . The cooking hob 12 comprises cooking regions 20a, 20b arranged on a left hal f and a right hal f of a cooktop 22 of the cooking hob 12 , which left and right halves are separated from each other by a suction opening 24 for an intake of the cooking vapours , the suction opening 24 being arranged alongside a cooktop centreline . The suction opening 24 is covered by a cover grid 26 for preventing items , e . g . cookware , to fall into the suction opening 24 . Instead of the cover grid 26 a lid may be used for entirely covering the suction opening when the extraction device 14 is out of use , but for the operation of the extraction device 14 the lid is pivotable into an upright open position . As is shown in Fig . 3 and as described in more detail further down below, each one of the two cooking regions 20a, 20b comprises two cooking zones 58 ' for a performance of cooking processes using a cooking utensil placed thereon (not shown) .

[0035] A housing 28 of the extraction device 14 is shown in Fig . 1 in transparent illustration . Said housing 28 provides a closed outer shell or channel segment for a flow of the sucked-in cooking vapours on their way from the suction opening 24 to an exhaust opening 30 in a base area 32 of the kitchen cabinet 16 . Said exhaust opening 30 is also covered, namely by an outlet grille 34 .

[0036] The flow of the sucked-in cooking vapours through the extraction device 14 is driven by the operation of an extraction fan 36 arranged inside of the housing 28 . Said extraction fan 36 comprises a bottom-sided intake opening 38 for sucking the cooking vapours from the interior space of the housing 28 . A rear-sided fan outlet is arranged for a hori zontal exit of the air blown out backwards from the extraction fan housing 42 . The fan outlet is connected to a first end of an air duct 44 designed as a rectangular tube and forms a second channel arranged downstream the above-mentioned first channel . Directly at the passage from the fan outlet to the air duct 44 , an air duct bending by 90 degrees is implemented, which redirects the air flow from hori zontal to vertical downwards . The air duct 44 may be guided alongside a rear side of the kitchen cabinet 16 and may be bent again by 90 degrees close to a rear lower edge of the kitchen cabinet 16 in order to direct the airflow towards exhaust opening 30 in the base area 32 of the kitchen cabinet 16 . Accordingly, the second end of the air duct 44 is connected to the exhaust opening 30 . The embodiment illustrated in Fig . 1 shows a solution of the air duct 44 with an inclined section of its downwardly directed portion, directed slightly to the right . Naturally, a solution with said portion arranged in an exact vertical direction is considerable as well .

[0037] The course of the cooking vapours from the cooking area through the extraction device 14 to a re-entry into ambient air is illustrated in Fig . 1 by dotted arrows 461to 465. On their way through the extraction device 14 , the cooking vapours pass through a filter assembly 48 , which is arranged downstream directly behind the suction opening 24 for providing a puri fication of the conveyed air . Said filter assembly 48 includes a filter carrier 50 supporting a filter element (not shown) that is usually configured for filtering out grease particles and droplets .

[0038] The structure of the combination appliance 10 with the air duct

[0039] 44 inside of the kitchen cabinet 16 and the exhaust opening 30 on the front of the cabinet 16 as shown in Fig . 1 is only one installation option . In other exemplary installations , the illustrated air duct 44 may be replaced by a direct blow-out opening at the cabinet rear side through an opening in the rearsided cabinet wall or by an air channel guided through a wall of the installation location of the combination appliance 10 , e . g . for an air exhaust outdoors .

[0040] The cross-sectional view of Fig . 2 further shows two power boards 54 , one for the left cooking region 20a and one for the right cooking region 20b, the power boards 54 providing cooking zones 58 ' in the left and right cooking regions 20a, 20b with electrical power . Attached to the bottom side of the power board 54 assigned to the right cooking region 20b, a further circuit board is arranged forming a control electronics 56 for the combination appliance 10 , which is configured for controlling the operation of the cooking hob 12 , especially for driving the induction coils 58 with a power level as speci fically selected by the user or as provided by a particular cooking program the user set at the beginning of each cooking process .

[0041] The combination appliance 10 is presented in Fig . 3 in a top view with the cooktop 22 being removed from the cooking hob 12 in order to allow a deeper insight . The cooking hob 12 is an induction cooking hob and the cooking zones 58 ' are defined by induction coils 58 that are arranged below the cooktop 22 of the cooking hob 12 . Fig . 3 illustrates the arrangement of the induction coils 58 below the cooktop 22 , which may be a glass ceramic plate . Each one of the induction coils 58 define a related cooking zone 58 ' . Further, a user interface 60 for the operation, in particular for user inputs , of the cooking hob 12 is arranged next to a left front edge of the cooktop 22 . The user interface 60 , which may also include a user interface function for the extraction device 14 , is not shown in Fig . 2 due to the cross-sectional illustration .

[0042] The present combination appliance 10 is equipped with a boil detection system, adapted to recogni ze a boiling of a fluid comprised in a cookware placed on one of the cooking zones 58 ' . To this end, a vibration sensor 62 is attached at the bottom surface of the cooktop 22 in a way that any vibration caused by a boiling fluid and transmitted to the cooktop 22 is measured and the related signal is forwarded to the control electronics 56 the vibration sensor 62 is connected to . In order to be capable of receiving the signals from anyone of the four cooking zones 58 ' in suf ficient strength, the vibration sensor 62 is positioned as centrally as possible on the bottom surface of the cooktop 22 , which position is therefore close to the cutout edge 64 of the suction opening 24 . According to Fig . 3 , a preferred position for the vibration sensor 62 is close to the rear edge ( in installation position of the combination appliance 10 ) of the cutout edge 64 , which position is indicated in Fig . 3 only by the installation position 66 , notably by means of a rectangular box, because of the removed cooktop 22 to which the vibration sensor 62 is attached . This preferred position is not only as central as possible , moreover, the rear cutout edge is distant from the user interface 60 , so that any interfering vibration signals from this electronic component is transmitted to the vibration sensor 62 in a mostly damped manner .

[0043] By Fig . 4 the bottom side of the cooktop 22 with an alternative positioning of the vibration sensor 62 is shown . Instead of an arrangement of the vibration sensor 62 on the rear side of the cutout edge 64 , the vibration sensor 62 is attached to a lateral side thereof , which lateral side is preferably adj acent to the cooking region 20a opposite to the arrangement area of the user interface 60 . The illustration of Fig . 4 also shows the vibration sensor 62 being a part of a little printed circuit board, which is fixed to the bottom side of the cooktop 22 .

[0044] The boil detection by means of a vibration analysis and a related cooking process adaptation is operated in that way that once the measured vibration is higher, more speci fically, by a predefined factor x higher, than an initial value measured at the beginning of a cooking program when the fluid is started to be heated, boiling state is assumed and a related software in the control electronics 56 takes measures in order to prevent the liquid base food from overboiling, e . g . by reducing the power level of the respective cooking zone 58 ' . In other words , said software prevents overboiling, once a threshold of the measured vibration is reached .

[0045] However, as previously mentioned, in order to take away the cooking vapours occurring during cooking processes the extraction device 14 of the combination appliance 10 is operated while the cooking process is performed . Accordingly, the extraction fan 36 is activated with a rotational speed, which the user or the control electronics may adapt to the amount of cooking vapours the current cooking process is generating . The present extraction fan 36 may be operable with three di f ferent speed levels . Due to the compact structure of the combination appliance 10 , the fan operation causes vibrations , which are also transmitted to a certain extent to the cooktop 22 , wherein the level of said fan operation vibrations depends on the current fan speed level . Therefore , the vibration sensor 62 not only receives vibration signals from the boiling fluid, which signals can be regarded as wanted signals , but said vibration signals from the extraction fan 36 , which are regarded as interfering or noise signals , are received as well . Even more , a further noise signal , resulting from electronic components operated with AC mains power, is included in the vibration signals as well . Consequently, the vibration sensor 62 measures a superposition of both the wanted signal and all said noise signals , so that a clear detection of the boiling of the fluid is not readily possible , because a first peak level of the superposed vibration signal , received when the fluid is not yet boiling, is not clearly distinguishable from a second peak level of the superposed vibration signal , received when the fluid is boiling . More speci fically, a ratio of said second peak level to said first peak level , which ratio shall be used for the identi fication of the boiling state , is too small .

[0046] In order to overcome this drawback, the control electronics 56 comprises an algorithm for filtering out the noise signals . The related method is based on the fact that the frequencies of the wanted signals and the noise signals are di f ferent to a far extent . Therefore , by eliminating and / or neutrali zing the frequencies belonging to the noise signals , the wanted signals can be identi fied in the superposed signal and a respective detection of a boiling state is enabled . Said algorithm particularly bases its methodology upon mathematical technique of Fourier trans formation as well as a negative feedback compensation .

[0047] The method for a signal processing and a following boiling detection process is particularly based on the fact that the signal detected by the vibration sensor 62 is a function of the acceleration a of the particular point of the cooktop 22 , which is defined by the position of the vibration sensor 62 , over the time t . The following steps are applied : In a first step, the noise signals resulting from the AC mains power are removed from the detected and transmitted vibration signal . Due to the fact that the related frequency is fixed and known, the related algorithm may base on common filtering methods .

[0048] In a second step, the noise signals resulting from the fan operation have to be eliminated as well . To this end, the output signal , provided after the detected and transmitted vibration signal has gone through said first step, gets trans formed by the Fourier trans formation from the time-domain to the frequency-do- main . Depending on the speed level of the extraction fan 36 , this operated component generates related frequencies . By means of the Fourier trans formation the frequencies of the extraction fan 36 are identi fied and neutrali zed by negative feedback compensation . After removing and neutrali zing said speci fic frequencies , the function of a processed acceleration apover time t can be analysed .

[0049] An example for a diagram "acceleration over time" for a first fan speed level is shown by Fig . 5 , wherein the illustrated function is already the result of the respective detected and transmitted vibration signal having gone through the first step, i . e . the noise signals resulting from the AC mains power are already eliminated . The x-axis of the diagram represents the time in seconds , and the y-axis represents the acceleration a, with subtracted AC mains power noise signal , in m / s2. The period of 0 to about 180 sec represents the initial heating phase , when the fluid is heated up but is not yet boiling . During this initial phase the measured acceleration peak value is oscillating around an average value of about 550 m / s2. At about 180 sec the boiling phase is started, represented by a rising peak value , reaching about 1000 m / s2, when the fluid has its highest boiling point. At this point in time a heating parameter is modified by the user or the cooking program in order to prevent the fluid from overboiling. Consequently, the peak value goes down.

[0050] As already indicated, the difference between the peak levels at the highest boiling point and during the initial phase is too small for a clear boiling detection. The calculation of the ratio of above-identified values is about 1000 / 550 » 2.

[0051] Fig. 6 represents the diagram "processed acceleration over time" for the first fan speed level, with the function of Fig. 5 having gone through the second step, i. e. processed by Fourier transformation with removing and neutralizing the specific frequencies sourcing from the operation of the extraction fan 36. It is directly notable that the removed frequencies result in a decreased initial value 70 by around 400 m / s2, so that a processed initial value 70 of about 150 (i.e. ^550-400) m / s2is provided. Approximately the same decrease is received for the peak point value 72 at the highest boiling point, resulting in a respective processed peak point value 72 of about 600 (i.e. »1000- 400) m / s2. A calculation of the ratio of these processed values 70, 72 provides a quantity of about 600 / 150 = 4, which quantity allows a clear detection of the boiling state.

[0052] Finally, by Fig.7 a diagram "processed acceleration over time" for a second speed level of the extraction fan 36 is provided, which second speed level is higher than the first speed level. The rectangular box 68 in each one of the Figs. 6 and 7 indicates the initial value 70 of the acceleration, when the cooking process is started and no boiling takes place. More specifically, an average signal value is calculated from a predefined time interval, which is, for example, in a range around the first two minutes, defining said initial value 70. The related different vibration signals of around 150 m / s2according to Fig. 6 and around 300 m / s2according to Fig. 7 result from the different fan speed levels, even though the specific frequencies sourcing from the operation of the extraction fan 36 have been removed and neutralized by Fourier transformation at this stage. As is further visible, the peak point values 72 of the two diagrams of Figs. 6 and 7 at around 265 or 215, respectively, seconds, at which boiling takes place, are different as well. The difference not only concerns the absolute value, but also the respective ratios between peak point value 72 and initial values 70, representing the previously mentioned factor x, are different. While said factor x of the diagram according to Fig. 6 is calculated by around x = 4, the factor x of the diagram according to Fig. 7 is calculated by around x = 13 (^3900 / 300) . More generally, the factor x between the peak point value 72 (indicating boiling point of the fluid) and the initial value 70 depends on the speed level of the extraction fan 36, and each speed level is related to a particular factor x. The different factors x are constants for each speed level. Consequently, with knowing the speed level of the extraction fan 36 by measuring the initial value 70, or more specifically the average signal value of the first around two minutes, the related factor x has to be considered for calculating the peak point value 72, so that boiling is detected as soon as the calculated peak point value 72 is measured by the vibration sensor 62.

[0053] Finally, although a combination appliance 10 with specific dimensions is presented by Figs. 1 to 4, the herein described setups of combination appliance 10 may be applicable to all known sizes of cooking hobs 12 and respective combination appliances 10 with a width of at least 580 mm. Specifically depending on the size of the cooking hob 12, three, four or five cooking zones may be provided. Although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings , it is to be understood that the present invention is not limited to these precise embodiments , and that various other changes and modi fications may be af fected therein by one skilled in the art without departing from the scope or spirit of the invention . All such changes and modi fications are intended to be included within the scope of the invention as defined by the ap- pended claims .

[0054] Moreover, features which are described in the context of separate aspects and embodiments of the invention may be used together and / or be interchangeable . Similarly, features described in the context of a single embodiment may also be provided separately or in any suitable sub-combination .

[0055] List of reference numerals

[0056] 10 combination appliance

[0057] 12 cooking hob

[0058] 14 downdraft extraction device

[0059] 16 kitchen cabinet

[0060] 18 kitchen countertop

[0061] 20a, 20b cooking regions

[0062] 22 cooktop

[0063] 24 suction opening

[0064] 26 cover grid

[0065] 28 extraction device housing

[0066] 30 exhaust opening

[0067] 32 base area

[0068] 34 outlet grille

[0069] 36 extraction fan

[0070] 38 intake opening

[0071] 42 fan housing

[0072] 44 air duct

[0073] 46i to 5 arrows indicating air flow

[0074] 48 filter assembly

[0075] 50 filter carrier

[0076] 54 power boards

[0077] 56 control electronics

[0078] 58 induction coils

[0079] 58 ' cooking zones

[0080] 60 user interface

[0081] 62 vibration sensor

[0082] 64 cutout edge

[0083] 66 installation area

[0084] 68 rectangular box

[0085] 70 initial value

[0086] 72 peak point value

Claims

Claims1. A cooking hob (12) , comprising or being connected to at least one wall or panel (22) , in particular a cooktop, an acceleration detection and / or measuring means (62) , particularly an acceleration sensor, more particularly comprising a microelectromechanical systems device, configured to detect an acceleration of a section or a reference point of the wall or the panel (22) of the cooking hob ( 12 ) , and a control unit (56) for controlling operating processes, the acceleration detection and / or measuring means (62) being connected to the control unit (56) for exchange of data, and forming a trigger element for the control unit (56) and being configured to provide a trigger signal for a control of a function and / or an operating process in the cooking hob (12) , characterized in that the cooking hob (12) further comprises an extraction device (14) or is connected, in particular physically attached or connected in a sound-conducting manner, to an extraction device (14) , which is configured to suck in cooking vapours arising on at least one cooking zone (58' ) of the cooking hob (12) as a result of a cooking process, wherein the cooking hob (12) and the extraction device (14) particularly form a combination appliance (10) , and wherein the control unit (56) is adapted to control the function and / or operating process in the cooking hob (12) based on the trigger signal of the acceleration detection and / or measuring means (62) during a parallel operation of the cooking hob (12) and the extraction device ( 14 ) .

2. The cooking hob (12) according to claim 1, characterized in that in an installation position of the cooking hob (12) , the extraction device (14) is arranged below the cooking hob (12) , preferably attached to a bottom side of the cooking hob (12) , and an extraction opening (24) is arranged in the cooktop (22) , preferably in a central position of a cooktop (22) , which cooktop (22) forms an upper wall or panel of the cooking hob (12) and includes the at least one cooking zone (58' ) of the cooking hob (12) , wherein the acceleration detection and / or measuring means (62) is arranged on or at the cooktop (22) , preferably on a bottom side of the cooktop (22) in the installation position of the cooking hob (12) , in close distance to the extraction opening (24) , preferably close to a peripheral edge of the extraction opening(24) , and / or distant from the control unit (56) and / or from a user interface (60) of the cooking hob (12) , in particular in the installation position of the cooking hob (12) on a rear side of a peripheral edge of the extraction opening (24) .

3. The cooking hob (12) according to claim 1 or 2, characterized in that the acceleration detection and / or measuring means (62) is configured to provide a trigger signal based on a cooking process performed on one of at least a first cooking zone( 58 ’ ) and a second cooking zone (58' ) , preferably on one of a plurality of cooking zones (58' ) distributed over the surface of the cooktop (22) , wherein the identification of the respective cooking zone (58' ) is performed by at least one of at least a first and a second acceleration detection and / or measuring sensor (62) ,at least one acceleration detection and / or measuring sensor (62) and at least an additional optical and / or temperature sensor, a detection or readout of power settings and / or current operating times of or related to the at least first cooking zone (58' ) and second cooking zone (58' ) , a detection means configured to evaluate the distance of the source of the acceleration to the acceleration detection and / or measuring means (62) and / or the direction of the acceleration.

4. The cooking hob (12) according to anyone of the preceding claims , characterized in that the acceleration detection and / or measuring means (62) is adapted to recognize and / or to evaluate vibrations originating from specific operating conditions, in particular from a boiling of a fluid included in a cookware placed on the cooking zone (58' ) , and the control unit (56) is adapted to control the function and / or operating process in the cooking hob (12) based on the recognized and / or evaluated vibrations.

5. The cooking hob (12) according to anyone of the preceding claims , characterized in that the cooking hob (12) , in particular the acceleration detection and / or measuring means (62) or the control unit (56) of the cooking hob (12) , includes a filter means configured to suppress or filter out vibration noise caused by the operation of the extraction device (14) and received by the acceleration detection and / or measuring means (62) .

6. The cooking hob (12) according to anyone of the preceding claims , characterized in that the control unit (56) is configured to control the function and / or operating process in the cooking hob (12) after reaching or exceeding a predefined signal threshold.

7. The cooking hob (12) according to claim 6, characterized in that the predefined signal threshold is based on or includes a factor x of a current vibration value detected and / or measured at a particular time during the cooking process in relation to an initial vibration value (70) detected and / or measured at an initial point in time or period of time of the cooking process, wherein the initial vibration value (70) is preferably based on an averaging of continuous or discrete initial vibration values (70) detected and / or measured during a time interval at the beginning of the cooking process.

8. The cooking hob (12) according to claim 7, characterized in that the extraction device (14) is operable in at least a first operating mode and a second operating mode, in particular operable with at least a first speed and a second speed of a ventilation means (36) of the extraction device (14) , wherein the acceleration detection and / or measuring means (56) is configured for a control of the function and / or operating process in the cooking hob (12) based on or as a result of an acceleration detection and / or measuring during each one of the first operating mode and the second operating mode of the extraction device (14) .

9. The cooking hob (12) according to claim 8,characterized in that the factor x between the current vibration value and the initial vibration value (70) is dependent on the current operating mode of the extraction device (14) , wherein the control unit (56) preferably includes or relies on a database comprising an assignment table that relates factors x to fan speeds .

10. The cooking hob (12) according to anyone of the preceding claims , characterized in that the control unit (56) includes an algorithm, which comprises a transformation of signals from time domain to frequency domain, wherein the transformation preferably includes a Fourier transformation algorithm.

11. The cooking hob (12) according to anyone of the preceding claims , characterized in that the control unit (56) includes an algorithm comprising a negative feedback compensation, which preferably performs or contributes to a neutralization of vibration noise caused by the operation of the extraction device (14) and received by the acceleration detection and / or measuring means (62) .

12. A combination appliance (10) including the cooking hob (12) according to anyone of the preceding claims and an extraction device (14) comprising a ventilation means (36) , wherein the extraction device (14) is configured to suck in cooking vapours arising on at least one cooking zone (58' ) of the cooking hob ( 12 ) .

13. A method for controlling a cooking hob (12) or a combination appliance (10) with a cooking hob (12) , which cooking hob (12) comprises at least one wall or panel (22) , an acceleration detection and / or measuring means (62) , and a control unit (56) for controlling operating processes, characterized in that the acceleration detection and / or measuring means (62) detects and / or measures an acceleration signal of a section or a reference point of the at least one wall or panel (22) of the cooking hob (12) , which acceleration signal bases on a superposition of a first vibration signal and a second vibration signal, wherein the first vibration signal originates from a cooking process performed on the cooking hob (12) and the second vibration signal originates from an operation of an extraction device (14) , which extraction device (14) is comprised in or which is connected, in particular physically attached or connected in a sound-conducting manner, to the cooking hob (12) , and wherein a function and / or an operating process in or of the cooking hob (12) is triggered as a result of the detected and / or measured acceleration signal.

14. The method according to claim 13, characterized in that the acceleration detection and / or measuring means (62) recognizes and / or evaluates a vibration signal originating from a boiling of a fluid included in a cookware placed on a cooking zone (58' ) of the cooking hob (12) , and the control unit (56) controls the function and / or the operating process in or of the cooking hob (12) based on a boiling condition of the fluid, wherein the recognized and / or evaluated vibration signal in particular forms the first vibration signal.

15. The method according to claim 14,characterized in that the influence of the second vibration signal is neutralized by making use of at least one of a transformation of the acceleration signal from time domain to frequency domain, which transformation preferably includes a Fourier transformation algorithm, and a negative feedback compensation.

16. The method according to claim 14 or 15, characterized in that a boiling condition of the fluid is identified during the run of an algorithm, which includes the steps of transformation of the acceleration signal from time domain to frequency domain, identifying the frequencies originating from the extraction device (14) , neutralizing the extraction device frequencies by a negative feedback compensation, preferably removing signals in a frequency range originating from components, in particular from electronic components, operated in the mains frequency or a multiple of the mains frequency.

17. The method according to anyone of the claims 14 to 16, characterized in that during the phase from starting the cooking process until identification of the boiling of the fluid, the operating conditions of the extraction device (14) , in particular a speed of a ventilation means (36) of the extraction device (14) , is kept constant.

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