METHOD FOR CONTROLLING A COOKING APPLIANCE

Abstract

The invention relates to a method for controlling a cooking appliance (1) with a temperature sensor (5), the cooking appliance (1) comprising at least one heating power transferring element (2) for heating a cookware item (3) placed on a cooking support (4), the method comprising the steps of: —Gathering temperature information related to the cookware item (3) or its content with the temperature sensor (5) at or in the cookware item (3), —after a heat-up process, gathering information regarding a power reduction action initiated by a user input; —evaluating temperature information provided by the temperature sensor (5), said temperature information being correlated with the temperature of the cookware item (3) or the cookware content; —providing temperature lock information to the user if the variation of the temperature of the cookware item (3) or the cookware content is within a certain temperature variation range; —after providing temperature lock information, receiving temperature lock confirmation from the user; —after receiving temperature lock confirmation, controlling the provision of heat energy to the cookware item (3) or the cookware content based on temperature information provided by the temperature sensor (5) such that the temperature of the cookware item (3) is maintained within a given temperature range.

Claims

1. Method for controlling a cooking appliance with a temperature sensor, the cooking appliance comprising at least one heating power transferring element for heating a cookware item placed on a cooking support, the method comprising the steps of: gathering temperature information related to the cookware item or its content with the temperature sensor at or in the cookware item, after a heat-up process, gathering information regarding a power reduction action initiated by a user input; evaluating the temperature information provided by the temperature sensor, said temperature information being correlated with a temperature of the cookware item or the cookware item content; providing temperature lock information to the user if a variation of the temperature of the cookware item or the cookware content is equal to or lower than a certain temperature variation value; after providing the temperature lock information, receiving a temperature lock confirmation from the user; after receiving the temperature lock confirmation, controlling provision of heat energy to the cookware item or the cookware content based on the temperature information provided by the temperature sensor such that the temperature of the cookware item or the cookware item content is maintained within a given temperature range.

2. Method according to claim 1, wherein the temperature information at a point of time at which said temperature lock information is received is used as a temperature control target value, and/or wherein the temperature lock information received from the user may be to hold a current temperature, and/or wherein the temperature lock information received from the user may be to adjust the current temperature by a predetermined adjustment value.

3. Method according to claim 2, wherein the provision of heat energy to the cookware item is controlled such that the temperature information provided by the temperature sensor is kept in a temperature range provided around the temperature control target value.

4. Method according to claim 1, wherein the temperature lock information is visual information provided at a user interface.

5. Method according to claim 1, wherein the temperature sensor comprises a resistor changing its resistance value depending on its temperature.

6. Method according to claim 5, wherein the temperature sensor is an NTC-thermistor.

7. Method according to claim 5, wherein the temperature information is derived by periodic sampling of a voltage value provided at the temperature sensor.

8. Method according to claim 1, wherein a heating procedure of the cooking appliance is recorded in a recording mode and information regarding the heating procedure is stored in order to reuse said information for a further heating procedure.

9. Method according to claim 1, wherein the cooking appliance is an induction cooking appliance.

10. Method according to claim 1, wherein the temperature of the cookware item is estimated with an algorithm using power board parameters, including power consumption and/or switching frequency, as input values.

11. Cooking system comprising a temperature sensor and a cooking appliance, the cooking appliance comprising at least one heating power transferring element for heating a cookware item placed on a cooking support and a user interface at least for receiving a command input of a user, the temperature sensor being configured to provide information regarding a temperature correlated with the cookware item or its content, the user interface being configured to allow the user to control heating power energy supplied by the at least one heating power transferring element, to provide temperature lock information and to input temperature lock confirmation, the cooking appliance further comprising: a control unit configured to perform the method of claim 1.

12. Cooking system according to claim 11, wherein the control unit is configured to control provision of heat energy to the cookware item such that said temperature information provided by the temperature sensor is kept in a temperature range provided around a temperature control target value, said temperature control target value being a temperature value at a point of time at which the temperature lock information is received.

13. (canceled)

14. Cooking system according to claim 11, wherein the temperature sensor comprises an NTC-thermistor.

15. Cooking system according to claim 11, comprising a storage configured to store information regarding a heating procedure of the cooking appliance in a recording mode, the cooking appliance being further configured to reuse stored information for a further heating procedure.

16. Cooking system according to claim 11, the cooking appliance being an induction cooking appliance.

17. Cooking system according to claim 11, wherein the temperature sensor is part of the cooking appliance and is provided below the cooking support, or wherein the temperature sensor is a food sensor wirelessly coupled with the control unit and/or the internet.

18. Cooking system according to claim 11, wherein the temperature sensor is combined with an algorithm for estimating the cookware temperature.

19. Cooking system according to claim 11, wherein the temperature sensor is part of the cookware item or is configured to be placed into the cookware item.

20. A method for controlling a cooking appliance comprising a heating power transferring element adapted to supply heating power for cooking, and a control unit adapted to control the heating power transferring element, the method comprising: operating the heating power transferring element to heat a cookware during a heating procedure; receiving sensor temperature values from a temperature sensor during the heating procedure, wherein said sensor temperature values correlate to an actual temperature of the cookware; and upon the sensor temperature values remaining confined within a predetermined temperature variation range over a predetermined time period, providing temperature lock information to notify a user that the temperature of the cookware, which is correlated to the sensor temperature, has achieved an essentially constant temperature; wherein after providing the temperature lock information, the user interface is configured to accept a user input to activate a temperature lock mode during which the control unit operates the heating power transferring element to maintain the temperature of the cookware at the essentially constant temperature.

21. The method according to claim 21, further comprising monitoring to detect if a user manually lowers the heating power of the heating power transferring element during the heating procedure, wherein said predetermined time period commences after detecting that a user has manually lowered said heating power; wherein the temperature sensor is disposed adjacent to the cookware so that said temperature sensor values provide an indirect measure of the actual temperature of the cookware, and that changes in said temperature sensor values are time delayed compared to changes in the actual temperature of said cookware during the heating procedure.

22. The method according to claim 22, wherein the heating procedure is recorded in a storage of said appliance, said control unit recalling control parameters, including user inputs, from said heating procedure and re-executing the same to thereby reproduce a similar cooking function in a future heating procedure.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] The various aspects of the invention, including its particular features and advantages, will be readily understood from the following detailed description and the accompanying drawings, in which:

[0078] FIG. 1 shows an example top view on a cooking appliance comprising multiple heating zones;

[0079] FIG. 2 shows a schematic illustration of a cooking appliance with a cookware item placed on a cooking support; and

[0080] FIG. 3 shows a pair of temperature curves wherein a first temperature curve illustrates the temperature profile of the temperature at the cookware over time and the second temperature curve illustrates the temperature profile of the temperature at a temperature sensor over time.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0081] The present invention will now be described more fully with reference to the accompanying drawings, in which example embodiments are shown. The embodiments in the figures may relate to preferred embodiments, while all elements and features described in connection with embodiments may be used, as far as appropriate, in combination with any other embodiment and feature as discussed herein, in particular related to any other embodiment discussed further above. However, this invention should not be construed as limited to the embodiments set forth herein. Throughout the following description similar reference numerals have been used to denote similar elements, parts, items or features, when applicable.

[0082] The features of the present invention disclosed in the specification, the claims, examples and/or the figures may both separately and in any combination thereof be material for realizing the invention in various forms thereof.

[0083] FIG. 1 illustrates a schematic diagram of an electric cooking appliance 1, specifically an induction hob.

[0084] The induction hob 1 comprises multiple heating zones 1.1, 1.2. Each heating zone 1.1, 1.2 may be, for example, associated with one or more heating power transferring elements 2, specifically, one or more induction coils. In the present embodiment, each heating zone 1.1, 1.2 is associated with a single heating power transferring element 2. However, according to other embodiments, a heating zone 1.1, 1.2 may be associated with multiple heating power transferring elements 2.

[0085] In addition, the cooking appliance 1 comprises a user interface 4, based on which a user may control the cooking appliance 1. For example, based on the user interface 7, the user may control the power level of the heating zones 1.1, 1.2.

[0086] FIG. 2 a-c show schematic side sectional views of a cooking system with a cooking appliance 1 on which a cookware item 3 is placed. The cooking appliance 1 comprises a cooking support 4 on which the cookware item can be placed.

[0087] Below the cooking support 4, a heating power transfer element 2 is provided. The heating power transfer element 2 may be, for example, an induction coil. The heating power transfer element 2 is coupled with a heating power energy unit 9.

[0088] In order to determine the temperature of the cookware item 3, a temperature sensor 5 is provided either with the appliance or separately. Said temperature sensor 5 may be arranged below the cooking support 4 as shown in FIG. 2a. Thus, the temperature sensor 5 may be adapted to indirectly measure the temperature of the cookware item 3 based on the heat transmitted by the cookware item 3 through the cooking support 4. Alternatively, the temperature sensor 5 may be provided with the cookware item 3 as shown in FIG. 2b or may be a food sensor placeable in the cookware item 3 as shown in FIG. 2c.

[0089] The temperature sensor 5 may comprise a thermal resistor, i.e. a resistor which changes the resistance value depending on its temperature. Specifically, the temperature sensor 5 may be an NTC-thermistor (NTC: negative temperature coefficient).

[0090] The temperature sensor 5 may be coupled with a control unit 8. This coupling may be a wired coupling or a wireless coupling with a known wireless short range technology. The control unit 8 may be configured to receive temperature information from the temperature sensor 5 and provide temperature control based on said temperature information. The control unit 8 may be a central control unit. The control unit 8 may also be coupled with the heating power energy unit 9 in order to control the provision of heat to the cookware item 3.

[0091] In order to support the user of the cooking appliance 1 in keeping the temperature of the cookware item 3 constant or essentially constant, the cooking system and/or cooking appliance 1 is configured to perform a temperature control method.

[0092] FIG. 3 shows a diagram indicating the temperature of the cookware T.sub.cookware over time. In addition, the diagram includes a temperature curve indicating the temperature information T.sub.sensor measured by the temperature sensor 5 over time.

[0093] The temperature curves regarding T.sub.cookware and T.sub.sensor refer to a heating procedure, in which a cookware item 3 is heated up in a heat-up phase t.sub.heat_up. During said heat-up phase, the temperature of the cookware item 3 may rise from a start temperature T.sub.start.

[0094] After reaching a certain temperature T.sub.peak, which may be, for example the boiling temperature, the user may lower the heating power provided to the cookware item 3 (point of time t1). Said lowering of heating power may be performed due to an input of the user at the user interface 7.

[0095] Due to said lowering of heating power, the temperature of the cookware T.sub.cookware may lower and approximate to a constant temperature value.

[0096] As can be seen in FIG. 3, due to the indirect temperature measurement performed by the temperature sensor 5, temperature information T.sub.sensor follows the temperature of the cookware T.sub.cookware with a certain offset and/or a certain delay. However, also temperature information T.sub.sensor approaches to a constant temperature value.

[0097] In order to support the user in keeping the temperature of the cookware T.sub.cookware constant or essentially constant over time, the control unit 8 may monitor if the heating power is lowered by means of a certain input at the user interface 7.

[0098] If such lowering action is recognized, the control unit 8 is configured to monitor the decay of temperature information T.sub.sensor. More specifically, the control unit 8 may monitor if the variation of the temperature information T.sub.sensor stays within a given temperature variation range. Even more specifically, the control unit 8 may monitor if the variation of the temperature information T.sub.sensor stays within the temperature variation range in a certain period of time. Said monitoring may be performed by sampling the electrical signal provided by the temperature sensor 8 and processing said sampled information by the control unit 8.

[0099] For example, after recognizing a lowering of heating power by a user input, the control unit 8 may constantly or at certain intervals check if the variation of temperature information T.sub.sensor within a certain period of time is equal or lower than a certain temperature variation value. Said temperature variation value may be the difference between an upper and a lower temperature boundary.

[0100] If the variation of temperature information T.sub.sensor within a certain period of time is equal or lower than a certain temperature variation value (point of time t2), the control unit 8 may provide temperature lock information. Said temperature lock information may be indicative for the user that the cookware temperature has reached a constant or essentially constant value.

[0101] The temperature lock information may be visually recognizable information and/or audible information. The temperature lock information may be provided at or via the user interface 7. For example, the temperature lock information may be a light signal provided at the user interface 7.

[0102] After the provision of temperature lock information, the user is able to activate a temperature lock mode. Said activation may be performed, for example, by a certain user input. The control unit 8 may receive a temperature lock confirmation. After receiving said temperature lock confirmation, the automatic temperature control may be started.

[0103] The control unit 8 may use the present temperature information as a target value for the automatic temperature control. The control unit 8 may control the provision of heating power provided to the heating power transferring element 2 such that the temperature information provided by the temperature sensor 5 is kept within the a given temperature range 6. Said temperature range 6 is schematically illustrated in FIG. 3. Thereby the temperature of the cookware item 3 is kept constant or essentially constant without user interaction.

[0104] According to an embodiment, the cooking appliance 1 may be configured to perform a recording mode, in which information regarding the heating procedure is gathered and stored. Thus, the cooking appliance 1 may comprise a storage for storing gathered information. In addition, the cooking appliance 1 may provide, for example, at the user interface 7 a cooking procedure menu, which can be used for defining a certain entry for a certain cooking procedure. An example for such cooking procedure may be, for example, a cooking procedure for boiling pasta in a certain cookware item. So, for example, the user can define a new entry or folder in said cooking procedure menu which is associated with certain cooking procedure information. Said entry or folder can be selected later on in order to reuse stored cooking procedure information for the cooking procedure.

[0105] More in detail, the cooking appliance 1 is configured to store a certain cooking procedure. Said storing can be initiated before starting the cooking process. Alternatively, the cooking appliance 1 may be adapted to buffer cooking procedure information during a cooking procedure and storing of said cooking procedure information can be initiated during the cooking procedure or after finishing the cooking procedure.

[0106] Said cooking procedure information may, for example, comprise information regarding the heating power provided to the cookware item 3, regarding the period of time in which said heating power is provided to the cookware item 3, changes of heating power, the duration of the heating process etc.

[0107] After storing said cooking procedure information, the user is able to reuse cooking procedure information later on for a similar or identical cooking procedure.

[0108] It should be noted that the description and drawings merely illustrate the principles of the proposed invention. Those skilled in the art will be able to implement various arrangements that, although not explicitly described or shown herein, embody the principles of the invention.

LIST OF REFERENCE NUMERALS

[0109] 1 cooking appliance [0110] 1.1 heating zone [0111] 1.2 heating zone [0112] 2 heating power transferring element [0113] 3 cookware item [0114] 4 cooking support [0115] 5 temperature sensor [0116] 6 temperature range [0117] 7 user interface [0118] 8 control unit [0119] 9 heating power energy unit