DE102012222165A1 - Cooking appliance - Google Patents

Abstract

The cooking device (1) has a cooking space (2) for cooking food, at least one sensor (3) arranged in the cooking space (2) for determining a current signal curve (AS) of a gas concentration in the cooking space (2), a memory (4 ) for storing a plurality of reference signal profiles (R1-R3) for the gas concentration in the cooking space (2), and a control device (5) for determining a remaining cooking time (RG) of the item to be cooked by comparing the determined current signal profile (AS) with the plurality the stored reference waveforms (R1-R3).

Description

The present invention relates to a cooking appliance, such as an oven, a microwave or a steamer. Furthermore, the invention relates to a method for operating a cooking appliance.

A conventional cooking appliance has a cooking chamber for cooking food, a control device for carrying out a plurality of predetermined cooking programs and a user interface coupled to the control device for actuating the control device. The user can select a specific cooking program via the user interface. The controller then executes the selected cooking program.

It is known when cooking food to indicate the end of the cooking time to the user via a display on the cooking appliance. Furthermore, methods for determining the remaining cooking time of the food are known. For example, such methods are in the documents DE 103 27 861 B4 and DE 10 2004 049 927 A1 described. In these methods, the slopes of signal traces of gas concentrations in the cooking chamber can be evaluated to determine a remaining cooking time for cooking the food.

Against this background, an object of the present invention is to improve the determination of a residual cooking time of the food in the cooking appliance.

According to the invention, a cooking device is proposed which has a cooking chamber for cooking food, at least one sensor arranged in the cooking chamber for determining a current signal curve of a gas concentration in the cooking chamber, a memory for storing a plurality of reference signal curves for the gas concentration in the cooking chamber, and a control device for determining a remaining cooking time of the cooking product by means of a comparison of the determined current signal course with the plurality of stored reference signal waveforms.

An advantage of the determination of the residual cooking time according to the invention is that it can be determined or calculated very precisely. Furthermore, in the determination according to the invention of the residual cooking time, no input of the user, for example the weight of the food to be cooked, is necessary. Furthermore, the reference signal curves can be learned during the operation of the cooking appliance, so that the determination of the remaining cooking time during the lifetime of the cooking appliance can be further refined and extended to a larger number of dishes.

In this case, in particular that reference signal profile is selected which has a minimum deviation from the current signal profile. Each Referenzsignalverlauf is assigned a Gesamtgarzeit, from which then the Restgarzeit can be calculated in a simple manner depending on the already required cooking time. By determining the remaining cooking time, the user can estimate the end of the cooking process and be prepared to be the expected Garende the cooking appliance to take the food or cooking food from the oven.

The Restgarzeit refers to the time that is still needed to cook the food in the oven, especially in the currently set cooking program. At the beginning of the cooking, the remaining cooking time and the total cooking time correspond.

In one embodiment, the cooking appliance has a display device that is configured to display the determined remaining cooking time to a user. The display device is designed, for example, as a touch-sensitive screen (touchscreen) and integrated in a user interface.

The user interface is in particular coupled to the control device and set up to control the control device. In this case, the control device is set up to output a selected cooking program, the specific remaining cooking time and potentially further cooking-related data to the user by means of the user interface. The user interface has, for example, input buttons and the touch-sensitive screen.

In a further embodiment, a specific total cooking time is assigned to the respective reference signal profile of the plurality of reference signal profiles. In this case, the control device is set up to use the comparison to select the reference signal course with a minimum distance to the specific current signal course and to determine the remaining cooking time as the difference between the total cooking time assigned to the selected reference signal course and a start time of the cooking. The cooking appliance preferably has a timer for recording the start time of the cooking.

In another embodiment, the controller is configured to calculate an average absolute deviation between the determined current waveform and each of the stored reference waveforms and to select the reference waveform having the calculated minimum mean absolute deviation for determining the remaining cooking time.

In a further embodiment, the memory comprises a database for storing N reference signal waveforms. In this case, the database stores a data record for each of the N reference signal waveforms. The respective data record comprises a chronological sequence of reference signal values of the gas concentration in the cooking chamber and an associated overall cooking time for the food to be cooked in the cooking chamber.

The following example illustrates the above embodiments regarding the reference waveforms and the determination of the remaining cooking time. The database comprises - as stated above - the total cooking time for the respective reference signal waveform. In addition, signal values at selected times, for example 5 minutes, 6 minutes or the like, are stored up to a predetermined end time, eg 20 minutes. The example extract from a database below comprises three data sets for three curves k (k ε {1, 2, 3}). In this case, the control device measures the signal value at the times indicated in the database, in this example at times 5, 6, 8, ... 20 minutes, and compares the current measured signal values with the values of the database. The number of records in the database is denoted by N. Structure of the database (example with N = 3 data records) Curve no. K Cooking time in minutes F (t = 5 min) F (t = 6 min) F (t = 7 min) ... F (t = 19 min) F (t = 20 min) 1 30 4 5 7 ... 34 35 2 45 3 4 5 ... 23 23 3 60 3 3 5 ... 18 19

For each data set k, the control device forms the mean absolute deviation MAA:

The symbol "| x |" means the amount (= absolute value) of the argument x: | x | = x for x ≥ 0; -X otherwise F _akt (t) is the current signal value at time t. F _k (t) is the signal value of the curve no. K of the database at time t.

The controller looks for the value MAA (k) which is the smallest. MAAmin (kbest) = Min (MAA (1), MAA (2), ... MAA (N)) That is, the curve no. Kbest fits best to the current waveform. The remaining time displayed is then the total duration of the curve kbest stored in the database, less the cooking time that has already passed.

The tables below juxtapose the extract of the above databases with the three datasets and an exemplary current waveform. For each date stored in the database, the absolute deviation is calculated from the current signal value minus the signal value of curve k of the database. The respective deviations are summed up and are shown in column MAA (k). The controller then determines the minimum of MAA (k). In the example below, this is found in the curve k = 1. Consequently, the curve k = 1 best suits the current signal curve. The total duration is thus 30 minutes. At time t = 20 minutes, therefore, the remaining time is calculated from the difference between 30 minutes and 20 minutes (30 minutes-20 minutes = 10 minutes).

In a further embodiment, the cooking appliance has a temperature sensor arranged in the cooking chamber for receiving a heating curve of the cooking chamber. In this case, the control unit is set up to determine the remaining cooking time by means of the comparison of the determined current signal profile with the plurality of stored reference signal profiles and in dependence on the recorded heating curve.

By using the current heating curve to determine the remaining cooking time, their calculation can be further specified.

In a further embodiment, the at least one sensor is configured to determine an oxygen concentration in the cooking chamber, a nitrogen concentration in the cooking chamber and / or a moisture concentration in the cooking chamber. In particular, the at least one sensor comprises an oxygen sensor for determining the oxygen concentration in the cooking chamber, a nitrogen sensor for determining the nitrogen concentration in the cooking chamber and a moisture sensor for determining the moisture concentration in the cooking chamber.

In another embodiment, the memory is configured to store a plurality of oxygen reference waveforms, a plurality of nitrogen reference waveforms, and / or a plurality of humidity reference waveforms.

In this case, the control device is preferably configured to determine the remaining cooking time of the cooking product by means of a comparison of the specific current signal curve of the oxygen concentration with the plurality of oxygen reference signal curves, by means of a comparison of the determined current signal curve of the nitrogen concentration with the plurality of nitrogen reference signal curves and / or by means of a To determine comparison of the determined current moisture concentration waveform with the plurality of humidity reference waveforms.

By using a plurality of different sensors for determining different gas concentrations, the calculation of the remaining cooking time can be further refined and improved.

In a further embodiment, the control device is configured to record the signal concentration of the gas concentration in the cooking chamber determined by the sensor during cooking carried out by a user and to store the recorded signal profile as reference signal profile in the memory.

As a result, the cooking appliance can learn adaptively and thus further improve the determination of the remaining cooking time.

In a further embodiment, the control device is set up to relate the signal values of the current signal waveform and the stored reference signal waveforms to a predetermined reference value.

By relating the signal values to a predetermined reference value, an error evaluation by an offset, i. by a parallel offset of the curves, reduced or prevented. For example, the reference value used is the remaining cooking time at one minute cooking time.

In a further embodiment, the control device is adapted to determine the remaining cooking time of the food during the total cooking time of the food several times, in particular at predetermined time intervals. As a result, the current remaining cooking time can be updated and displayed updated.

In a further embodiment, the control device is set up to start a timer (timer) initialized with the determined remaining cooking time at the time of determining the remaining cooking time and to automatically end the cooking of the cooking appliance after the initialized timer has expired.

This stops cooking at the right time without the need for user intervention. Consequently, it is ensured that the food is cooked optimally.

In a further embodiment, the cooking appliance has a communication interface which is set up to receive updated reference signal waveforms from a server via a network. Accordingly, the communication interface can also be set up to transmit the reference signal waveforms stored in the memory to the server via the network.

By providing the communication interface, the cooking appliance is online-enabled and can both load updated reference waveforms and provide updated reference waveforms to other cooking appliances via the network and the server.

In a further embodiment, the cooking appliance comprises a probe for determining the permittivity of the food in the cooking chamber. The control device can then be set up to additionally calculate the remaining cooking time of the cooking product as a function of the specific permittivity of the cooking product.

The probe is inserted into the food. The inserted probe measures the frequency-dependent permittivity (dielectric constant) of the food by means of electrical DC and AC fields. The measured data are compared with stored data in the control device, similar to the spectrometry. By heating the food during the measurement, the measurement results can be even clearer.

The cooking appliance is for example an oven, a microwave, a steamer or a warming drawer.

Furthermore, a method for operating a cooking appliance with a cooking space for cooking food is proposed. In a first step, a plurality of reference signal curves for a gas concentration in the cooking chamber are stored. In a second step, a current signal curve of the gas concentration in the cooking chamber is determined. In a third step, a remaining cooking time of the cooking product is determined by means of a comparison of the determined current signal profile with the plurality of stored reference signal profiles.

Furthermore, a computer program product is proposed, which causes the execution of at least one step of a method for operating a cooking appliance, as explained above, on a program-controlled device.

A computer program product such as a computer program means can be provided or supplied, for example, as a storage medium, such as a memory card, USB stick, CD-ROM, DVD or in the form of a downloadable file from a server in a network. This can be done, for example, in a wireless communication network by the transmission of a corresponding file with the computer program product or the computer program means.

Further advantageous embodiments and aspects of the invention are the subject of the dependent claims and the embodiments of the invention described below. Furthermore, the invention will be explained in more detail by means of preferred embodiments with reference to the attached figures.

It shows:

1 a schematic view of a first embodiment of a cooking appliance;

2 a schematic view of a second embodiment of a cooking appliance;

3 a schematic view of a third embodiment of a cooking appliance;

4 a schematic view of a fourth embodiment of a cooking appliance;

5 a schematic flow diagram of an embodiment of a method for operating a cooking appliance;

6 an example with four waveforms of four data sets; and

7 the example of 6 with a current waveform.

In the figures, the same or functionally identical elements have been given the same reference numerals, unless stated otherwise.

In 1 is a schematic view of a first embodiment of a cooking appliance 1 shown. The cooking appliance 1 has a cooking space 2 for cooking food (not shown). For example, the cooking appliance 1 designed as an oven. In this embodiment, the cooking chamber 2 then be referred to as a stovepipe.

In the oven 2 is a sensor 3 arranged, which a current signal curve AS of a gas concentration in the cooking chamber 2 certainly. For example, the sensor 3 adapted to an oxygen concentration in the cooking chamber 2 , a concentration of nitrogen in the oven 2 or a moisture concentration in the cooking chamber 2 to determine.

Furthermore, the cooking appliance 1 a memory 4 for storing a plurality of reference signal profiles R1-R3 for the gas concentration in the cooking chamber 2 on. The memory is for example a read-only memory. In particular, the memory includes 4 a database for storing a plurality N of reference waveforms. For each of the N reference waveforms R1-R3, the database stores a record. The respective data record comprises a chronological sequence of reference signal values R1, R2 or R3 of the gas concentration in the cooking chamber 2 and an associated total cooking time for the food in the cooking chamber 2 , Without limitation of generality, the storage device stores 4 of the cooking appliance 1 three reference signal waveforms R1-R3. The number of stored reference waveforms R1-R3 in the memory 4 can also be a few hundred or a thousand.

Furthermore, the cooking space 2 a control device 5 on. The control device 5 is for controlling the cooking appliance 1 and in particular set up for carrying out a plurality of predetermined cooking programs for cooking the food. The control device 5 is designed, for example, as an embedded system or as a microcontroller.

The control device 5 is also configured to determine a remaining cooking time RG of the cooking product by means of a comparison of the determined current signal curve AS with the plurality of stored reference signal curves FR1-R3. In this case, the respective reference signal R1-R3 of the plurality is in the memory 4 stored reference waveforms R1-R3 associated with a specific total cooking time. The control device 5 then selects by means of the comparison, the reference waveform R1-R3, which has a minimum distance to the particular current waveform AS. The remaining cooking time RG determines the control device 5 then as the difference between the total cooking time associated with the selected reference waveform R1-R3 and a cooking start time. The start time of cooking is by the controller 5 detected by signal technology.

In particular, the control device 5 arranged to calculate a mean absolute deviation between the determined current waveform AS and each of the stored reference waveforms R1-R3 and to select the reference waveform R1-R3 having the calculated minimum mean absolute deviation for determining the remaining cooking time RG. Furthermore, the cooking appliance 1 a display device 6 on, which with the control device 5 is coupled and is adapted to display the particular remaining cooking time RG a user.

The control device 4 is also designed in particular by the sensor 3 during a cooking performed by a user, the gas concentration in the cooking chamber is determined 2 and as a reference signal waveform R1-R3 in the memory 4 save.

Furthermore, the control device 5 for example, designed to relate the signal values of the current signal waveform AS and the stored reference signal waveforms R1-R3 to a predetermined reference value. As a result, advantageously, an offset of the individual signal values can be avoided.

The control device 5 determines the Restgarzeit RG of the food during the entire cooking time of the food preferably several times, especially at predetermined intervals. The predetermined time intervals can be a few seconds or even a few minutes.

Furthermore, the control device 5 also be set up to start at the time of determining the Restgarzeit RG initialized with the Restgarzeit RG timer or timer and automatically stop the cooking of the food after the expiry of the initialized timer and automatically.

2 shows a second embodiment of a cooking appliance 1 , The second embodiment of the 2 is based on the first embodiment of 1 and differs only in that the second embodiment of the 2 three different sensors 8th . 9 and 10 includes. The cooking appliance 1 of the 2 includes an oxygen sensor for this purpose 8th for determining a current signal curve AO of the oxygen concentration in the cooking chamber 2 , a nitrogen sensor 9 for determining a current signal curve AN of the nitrogen concentration in the cooking chamber 2 and a humidity sensor 10 for determining a current signal curve AF of the moisture concentration in the cooking chamber. The memory saves 4 of the 2 a plurality of oxygen reference signal waveforms R1, a plurality of nitrogen reference signal waveforms R2, and a plurality of humidity reference signal waveforms R3. The control device 5 of the 2 is set up for the remaining cooking time RG of the cooking product by means of a comparison of the determined current signal curve OA of the oxygen concentration with the plurality of oxygen reference signal curves R1, by means of a comparison of the determined current signal curve AN of the nitrogen concentration with the plurality of nitrogen reference signal curves R2 and by means of a comparison the determined current waveform AF of the moisture concentration with the plurality of moisture reference waveforms R3 to determine.

In 3 is a third embodiment of a cooking appliance 1 shown. The third embodiment of 3 is based on the second embodiment of the 2 and has all the features of the second embodiment. In addition, the cooking appliance has 1 of the 3 one in the oven 2 arranged temperature sensor 7 for picking up a heating curve AT of the cooking chamber 2 , The control device 5 of the 3 is then set to the Restgarzeit RG by means of the reference to 2 to be determined comparisons and in dependence on the heating curve AT.

4 shows a fourth embodiment of a cooking appliance 1 , The fourth embodiment of 4 is based on the first embodiment of 1 , but can also be in the second or third embodiment of the 2 or the 3 based. The cooking appliance 1 of the 4 has a communication interface 11 , The communication interface 11 is adapted to update reference waveforms R1-R3 over a network 12 from a server 13 to receive and those in the store 4 stored reference signal waveforms R1-R3 to the server 13 over the network 12 transferred to. The communication interface 11 includes, for example, an Ethernet interface. The network 12 is for example the Internet or a Local Area Network (LAN).

In 5 is a schematic flow diagram of an embodiment of a method for operating a cooking appliance 1 shown (see 1 ). The cooking appliance 1 has a cooking space 2 for cooking food and a control device 3 for performing a plurality of predetermined cooking programs P1-P3.

In step 501 is a plurality of Referenzsignalverläufe R1-R3 for a gas concentration in the cooking chamber 2 saved.

In step 502 becomes a current waveform AS of the gas concentration in the cooking chamber 2 certainly.

In step 503 a Restgarzeit RG of the food is determined by means of a comparison of the particular current waveform AS with the plurality of stored Referenzsignalverläufe R1-R3.

6 shows an example with four waveforms 601 . 602 . 603 . 604 of four data sets and thus with four signal curves. There are the waveforms 601 . 602 . 603 . 604 filed at discrete times between 5 and 20 minutes.

In 7 is the example of 6 with a current waveform 701 shown. The current waveform 701 has the smallest deviation from the curve in this example 603 , Consequently, that is the curve 603 allocated baking time is crucial for the remaining cooking time.

Although the present invention has been described with reference to embodiments, it is variously modifiable.

LIST OF REFERENCE NUMBERS

1

 Cooking appliance

2

 oven

3

 sensor

4

 Storage

5

 control device

6

 display

7

 temperature sensor

8th

 oxygen sensor

9

 nitrogen sensor

10

 humidity sensor

11

 Communication Interface

12

 network

13

 server

501-503

 step

AS

 current waveform

A0

 current signal curve of the oxygen concentration

AT

 current signal curve of the nitrogen concentration

AF

 current waveform of the moisture concentration

AT

 current heating curve

R1-R3

 Reference waveform

RG

 The remaining cooking time

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10327861 B4 [0003]
• DE 102004049927 A1 [0003]

Claims (15)

Cooking appliance ( 1 ) with a cooking space ( 2 ) for cooking food, at least one in the cooking space ( 2 ) arranged sensor ( 3 ) for determining a current signal curve (AS) of a gas concentration in the cooking chamber ( 2 ), a memory ( 4 ) for storing a plurality of reference signal profiles (R1-R3) for the gas concentration in the cooking chamber ( 2 ), and a control device ( 5 ) for determining a remaining cooking time (RG) of the cooking product by means of a comparison of the determined current signal curve (AS) with the plurality of stored reference signal curves (R1-R3). Cooking appliance according to claim 1, characterized by a display device ( 6 ) which is arranged to display the determined remaining cooking time (RG) to a user. Cooking appliance according to claim 1 or 2, characterized in that the respective reference signal course (R1-R3) of the plurality of reference signal waveforms (R1-R3) is assigned a specific total cooking time, wherein the control device ( 5 ) is set up to select by means of the comparison the reference signal course (R1-R3) with a minimum distance to the determined current signal course (AS) and the remaining cooking time (RG) as the difference between the total cooking time associated with the selected reference signal course (R1-R3) Start time of cooking to determine. Cooking appliance according to claim 3, characterized in that the control device ( 5 ) is arranged to calculate an average absolute deviation between the determined current waveform (AS) and each of the stored reference waveforms (R1-R3) and the reference waveform (R1-R3) having the calculated minimum mean absolute deviation for determining the remaining cooking time (RG). Cooking appliance according to one of claims 1 to 4, characterized in that the memory ( 4 ) comprises a database for storing N reference waveforms (R1-R3), the database storing a record for each of the N reference waveforms (R1-R3), the respective data set containing a time series of reference signal values (R1-R3) Gas concentration in the cooking chamber ( 2 ) and an associated Gesamtgarzeit for the food in the cooking chamber ( 2 ). Cooking appliance according to one of claims 1 to 5, characterized by a in the cooking chamber ( 2 ) arranged temperature sensor ( 7 ) for receiving a heating curve (AT) of the cooking chamber ( 2 ), wherein the control device ( 5 ) is set up to determine the remaining cooking time (RG) by means of the comparison of the determined current signal curve (AS) with the plurality of stored reference signal curves (R1-R3) and in dependence on the recorded heating curve (AT). Cooking appliance according to one of claims 1 to 6, characterized in that the at least one sensor ( 3 ) is adapted to an oxygen concentration in the cooking chamber ( 2 ), a nitrogen concentration in the cooking chamber ( 2 ) and / or a moisture concentration in the cooking chamber ( 2 ). Cooking appliance according to claim 7, characterized in that the memory ( 4 ) is configured to store a plurality of oxygen reference waveforms (R1), a plurality of nitrogen reference waveforms (R2), and / or a plurality of humidity reference waveforms (R3). Cooking appliance according to claim 8, characterized in that the control device ( 5 ) is adapted to the cooking time (RG) of the cooking product by means of a comparison of the determined current waveform (A0) of the oxygen concentration with the plurality of oxygen reference signal curves (R1), by means of a comparison of the determined current waveform (AN) of the nitrogen concentration with the plurality of nitrogen reference waveforms (R2) and / or by comparing the determined current waveform (AF) of the moisture concentration with the plurality of humidity reference waveforms (R3). Cooking appliance according to one of claims 1 to 9, characterized in that the control device ( 5 ) is set up by the sensor ( 3 ) during a cooking carried out by a user (AS) the gas concentration in the cooking chamber ( 2 ) and the recorded waveform as a reference waveform (R1-R3) in the memory ( 4 ) save. Cooking appliance according to one of claims 1 to 10, characterized in that the control device ( 5 ) is adapted to relate the signal values of the current waveform (AS) and the stored reference waveforms (R1-R3) to a predetermined reference value. Cooking appliance according to one of claims 1 to 11, characterized in that the control device ( 5 ) is set up to determine the remaining cooking time (RG) of the food during the total cooking time of the food several times, in particular at predetermined time intervals. Cooking appliance according to one of claims 1 to 12, characterized in that the control device ( 5 ) is arranged to start at the time of determining the remaining cooking time with the certain Restgarzeit (RG) initialized timer and automatically stop the cooking of the food after the expiry of the initialized timer. Cooking appliance according to one of claims 1 to 13, characterized by a communication interface ( 11 ), which is adapted to update reference signal waveforms (R1-R3) over a network ( 12 ) from a server ( 13 ) and / or in the memory ( 4 ) stored reference waveforms (R1-R3) to the server ( 13 ) over the network ( 12 ) transferred to. Method for operating a cooking appliance ( 1 ) with a cooking space ( 2 ) for cooking food, with the steps: Save ( 501 ) of a plurality of reference signal profiles (R1-R3) for a gas concentration in the cooking chamber ( 2 ), Determining ( 502 ) of a current signal curve (AS) of the gas concentration in the cooking chamber ( 2 ), and determining ( 503 ) a Restgarzeit (RG) of the food by means of a comparison of the particular current waveform (AS) with the plurality of stored reference waveforms (R1-R3).

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