METHOD FOR OPERATING AN INDUCTION HOB

Abstract

In order to detect whether a cooking vessel with an integrated controller or intelligence is arranged over an induction heating coil on an induction hob, the induction heating coils emit a short individual coding. This can be detected and evaluated by the cooking vessel, with the result that the cooking vessel emits a signal which corresponds to this coding and is received by an external operating device or the induction hob for the purpose of locally assigning this cooking vessel to this induction heating coil.

Claims

1. A method for operating an induction hob having a plurality of induction heating coils, wherein: each said induction heating coil has a heating area, a cooking vessel can be arranged in a manner covering at least one said heating area, each said induction heating coil is designed to transfer energy for heating one said cooking vessel and is controlled by a converter for this purpose, each said cooking vessel has a transmitting apparatus with a transmitting antenna for transmitting a signal on a basis of received energy from one said induction heating coil, said heating area of said induction heating coil being at least partially covered by said cooking vessel, a receiving device is provided for a purpose of receiving signals from a transmitting apparatus of one said cooking vessel or from all said transmitting apparatuses of said cooking vessels on said induction hob, a controller is provided for receiving said signals from said receiving device and has or receives said information relating to transfer of energy from said induction heating coils, wherein the method has the following steps: at least one said cooking vessel is arranged over one said heating area of one said induction heating coil, a multiplicity of said induction heating coils are controlled to transfer energy in a pattern, wherein a duration and/or an amplitude are varied as coding, wherein said coding involves varying said amplitude of said transferred energy within said coding over time, in particular between zero and a coding maximum value, and/or varying said duration of said energy transfer, and/or varying said duration between two energy transfer operations, and/or varying a number of said energy transfer operations, if one said cooking vessel covers one said heating area of said induction heating coil which has transferred energy with a particular coding, said transmitting apparatus transmits a signal or a sequence of a plurality of signals, which uniquely depend on said coding and/or can be assigned to precisely said coding, to said receiving device, said controller receives said signals received by said receiving device and compares said signals with information relating to said energy transferred by said induction heating coils as codings in order to determine which coding of said transferred energy from one said particular induction heating coil matches a received signal or a sequence of a plurality of signals in order, on the basis thereof, to assign said cooking vessel transmitting said signal or said sequence of a plurality of signals to said heating area or to said induction heating coil associated said the heating area.

2. The method as claimed in claim 1, wherein one said cooking vessel has a receiving coil in order to store an alternating magnetic field of one said induction heating coil, which is used to transfer energy, as electrical energy in order to emit said signal by means of said transmitting antenna of said transmitting apparatus.

3. The method as claimed in claim 1, wherein an energy storage is provided in said cooking vessel and is connected to said receiving coil, wherein energy received by said receiving coil is stored in said energy storage, and wherein a signal or a sequence of a plurality of signals is emitted by said transmitting apparatus in accordance with said stored energy.

4. The method as claimed in claim 1, wherein energy received by said receiving coil is used directly to electrically control said transmitting antenna to transmit a signal or a sequence of a plurality of signals, wherein said length and/or strength of said at least one signal correspond(s) to a variance of said duration and/or amplitude of said coding.

5. The method as claimed in claim 4, wherein said transmitting antenna transmits a signal as soon as energy is transferred to said receiving coil by an induction heating coil, said heating area of which is covered by said cooking vessel, wherein said transmitting apparatus transmits a signal as long as energy is transferred from said induction heating coil to said receiving coil, and wherein said transmitting apparatus does not transmit a signal as soon as no more energy is transferred from said induction heating coil to said receiving coil.

6. The method as claimed in claim 1, wherein said transfer of energy in induction heating coils, in the case of which it is not known that or whether their heating area is covered by one said cooking vessel, is repeated frequently and/or regularly with a frequency or repetition frequency of less than 1 minute in order to detect one said cooking vessel arranged in said heating area.

7. The method as claimed in claim 1, wherein said transfer of energy from said induction heating coils for detecting cooking vessels arranged in said heating area is at least also carried out if a change in a coverage of one said heating area by one said cooking vessel is detected.

8. The method as claimed in claim 1, wherein said method is carried out on a mobile terminal or an external control device with a controller and a receiving device only when an app on said mobile terminal is active or when said external control device is activated.

9. The method as claimed in claim 2, wherein said method is carried out only when on said cooking vessel with one said receiving coil and on said transmitting apparatus has been discovered on said induction hob, wherein said cooking vessel also has an integrated circuit and at least one sensor.

10. The method as claimed in claim 1, wherein one said coding consists of pings or pulses which oscillate at an operating frequency or a resonant frequency of a resonant circuit comprising said induction heating coil, wherein a ping or a pulse has one or more oscillations with a total duration of between 1 sec and 500 sec.

11. The method as claimed in claim 10, wherein an interval between two said pings or said pulses within one said coding has a duration of a power supply half cycle of the power supply at 50 Hz or 60 Hz or a multiple thereof.

12. The method as claimed in claim 1, wherein said receiving device and said controller are arranged outside said induction hob in an external operating device, wherein said external operating device has operating elements and at least one display device.

13. The method as claimed in claim 1, wherein one said cooking vessel also has an integrated circuit in addition to said receiving coil and said transmitting apparatus.

14. The method as claimed in claim 13, wherein one said cooking vessel has at least one sensor, such as a temperature sensor or a pressure sensor, and an energy storage.

15. The method as claimed in claim 1, wherein, if all said induction heating coils are controlled to transfer energy for a purpose of detecting one said cooking vessel arranged in said heating area, energy is first of all transferred for a short time as a ping, there is then a pause, and a multiplicity of different codings are then generated using a varying number of short sequences of transferring energy and pausing or by waiting for a particular multiple of a waiting time, and each of said induction heating coils is controlled with a different coding, but each said of induction heating coils is always recurrently controlled with the same coding, for a purpose of transferring energy with said coding.

16. The method as claimed in claim 1, wherein said controller stores which of said cooking vessels is arranged in said heating area of which induction heating coil, wherein said controller detects cooking vessels newly arranged in one said heating area of one said induction heating coil in the same manner.

17. The method as claimed in claim 1, wherein said controller stores which of said cooking vessels is moved out of said heating area, which is detected by said controller on a basis of changes in operating parameters of said resonant circuit comprising said induction heating coil.

18. The method as claimed in claim 1, wherein transmission or transfer of one said coding stops as long as one said induction heating coil, after detecting and assigning one said cooking vessel, does not register any change or movement of said cooking vessel in its heating area by virtue of a change in operating parameters of a resonant circuit comprising said induction heating coil, wherein one said coding is transmitted to said induction heating coil or to all of said induction heating coils again only when a change or movement of said cooking vessel in their heating area is registered.

19. The method as claimed in claim 1, wherein all said induction heating coils begin to transmit a coding at the same time as transmitting energy.

20. The method as claimed in claim 1, wherein each said coding first of all has a ping or energy is briefly transferred for a purpose of synchronization, and each said induction heating coil has a different coding after said synchronization ping.

21. The method as claimed in claim 20, wherein, within all said codings, at least one further ping follows said synchronization ping at an interval of time, and a number of following pings corresponds to a numbering of said induction heating coils, wherein an interval of time within a coding is the same in each case up to the last ping before said next synchronization ping.

22. The method as claimed in claim 20, wherein, within all said codings, precisely one further ping follows said synchronization ping at an interval of time which is an integer multiple of an interval duration, wherein a number of said integer multiples of said interval duration of said precisely one further ping corresponds to a numbering of said induction heating coils.

23. The method as claimed in claim 19, wherein a binary number is transferred by means of said coding, wherein said binary distinction is made by transmitting a ping or no ping at points of a predefined time pattern in each case, wherein, before transferring said binary number, a ping is first of all transmitted or energy is briefly transferred for a purpose of synchronization or as one said synchronization ping as claimed in claim 19.

24. The method as claimed in claim 1, wherein, within all said codings, an interval of time between two successive pings is an integer multiple of an interval duration, wherein a number of said integer multiples of said interval duration between two successive pings corresponds to a numbering of said induction heating coils.

25. The method as claimed in claim 24, wherein all said codings have (n+1) said pings with (two to n) said different interval durations, wherein said interval durations are evaluated with respect to their combination.

26. The method as claimed in claim 1, wherein said transmitting apparatus transmits an item of processed information which has been evaluated from said coding received from one said induction heating coil.

27. The method as claimed in claim 1, wherein said coding is evaluated in said receiving device.

28. The method as claimed in claim 1, wherein said coding is evaluated in said controller.

29. The method as claimed in claim 1, wherein said method is carried out only on those induction heating coils, said heating area of which is assigned only to precisely one said cooking vessel.

30. An induction hob for carrying out the method as claimed in claim 1, wherein: said induction hob has a plurality of said induction heating coils, each of said induction heating coils has a heating area, each of said induction heating coil said is designed to transfer energy for heating one said cooking vessel and is controlled by a converter for this purpose, each of said cooking vessels has a transmitting apparatus with a transmitting antenna for transmitting a signal on a basis of received energy from one said induction heating coil, said heating area of which is at least partially covered by said cooking vessel, a receiving device is provided for a purpose of receiving signals from a transmitting apparatus of one said cooking vessel or from all said transmitting apparatuses of said cooking vessels on said induction hob, said induction hob has a controller which receives said signals from said receiving device and has or receives said information relating to transfer of energy from said induction heating coils.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Further advantages and aspects of the invention emerge from the claims and from the following description of preferred exemplary embodiments of the invention which are explained below on the basis of the figures, in which:

[0045] FIG. 1 shows a schematic illustration of an induction hob according to the invention in an arrangement having a cooking vessel placed on a heating area of an induction heating coil together with an external operating device,

[0046] FIG. 2 shows a simplified illustration of the functionalities of the cooking vessel with intelligence,

[0047] FIGS. 3 to 8 show different codings.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

[0048] FIG. 1 illustrates an arrangement 11 having an induction hob 13 according to the invention. The induction hob 13 has a hob panel 14, under which two induction heating coils 16a and 16b are arranged. In practice, there are advantageously more induction heating coils 16, for example four or six up to twenty or thirty in the above-mentioned flat-surface hobs.

[0049] The induction hob 13 also has a hob controller 18 which is connected to functional units of a converter apparatus 20, a transmitting/receiving device 22 and an operating module 24 on the underside of the hob panel 14. These functional units are each designed in a conventional manner. A radio standard for the transmitting/receiving device 22 can fundamentally be of various designs, as explained at the outset. It is advantageously from the above-mentioned possibilities of Bluetooth or BLE, but also Zigbee, WLAN or the like, as well as proprietary solutions without a universal standard.

[0050] Above the heating induction coils 16a and 16b, a heating area is respectively formed with an area which corresponds approximately to the area of the induction heating coils 16 in each case. A cooking vessel 27 is arranged in the heating area 17a or is placed onto the upper side of the hob panel 14 there. The cooking vessel 27 has a receiving coil 32 in a recess 30 in a base 29. The receiving coil 32 has a few turns and is arranged on the underside of the base 29 in such a manner that it is exposed and is not shielded from the magnetic field of the induction heating coil 16a by the rest of the base. This is important for the energy transfer described above. The receiving coil 32 is connected to a cooking vessel module 34 which is illustrated in an enlarged form in FIG. 2.

[0051] On the right, FIG. 1 illustrates an external operating device 46 which may be, on the one hand, a special operating device for the induction hob 13 or alternatively a mobile terminal such as a tablet computer or a smartphone. The external operating device 46 has a large-area display, as illustrated. It also has, as is known in particular for the mobile terminals mentioned, a receiving device, a transmitting device and a processor or an integrated circuit. A radio standard here matches the transmitting/receiving device 22, that is to say advantageously Bluetooth or BLE. Not much needs to be said with respect to the external operating device 46; a cooking program explained at the outset can run on it, for example by means of an app or a special program. The external operating unit illustrated is not absolutely necessary. Its function can likewise be integrated in an operating and control unit which is inside the hob.

[0052] FIG. 2 illustrates the cooking vessel module 34 in an enlarged form. The cooking vessel module 34 is connected to the receiving coil 32 by means of an electrical connection in the form of a cable or the like. In a similar manner, the cooking vessel module 34 is connected, in an electrically conductive manner, to a temperature sensor 36 which is arranged outside the cooking vessel module and is advantageously arranged inside the cooking vessel 27 according to FIG. 1, with the result that it is surrounded by water or food to be cooked situated there in and can determine the temperature thereof. This temperature sensor can likewise be embedded in the base of the cooking vessel if the base temperature is intended to be captured, rather than the temperature of the food to be cooked. Instead of the temperature sensor 36, yet further sensors such as pressure sensors, weight sensors or the like are alternatively or additionally conceivable.

[0053] The cooking vessel module 34 also has an energy storage 38 which is directly connected to the receiving coil 32. This may be a rechargeable battery and is advantageously an above-mentioned capacitor since it need not store particularly large amounts of energy, in particular if transmission is carried out using Bluetooth or BLE or Zigbee, but should do this as quickly and as loss-free as possible.

[0054] An integrated circuit 40 as a type of controller is provided in the cooking vessel module 34 and captures precisely energy or the signals or pings received by the receiving coil 32, advantageously with respect to the duration and/or interval and/or amplitude and totaled energy stored in the energy storage 38. The integrated circuit 40 controls a transmitting apparatus 42 with a transmitting antenna 44, advantageously constructed with the above-mentioned Bluetooth or BLE standard or Zigbee.

[0055] FIG. 3 illustrates a first example of a coding for four induction heating coils I1 to I4, by way of example. First of all, a synchronization ping illustrated using dotted lines can be simultaneously generated for all four induction heating coils, but this need not be the case. Such a synchronization ping and the further pings or pulses are advantageously generated in the manner mentioned at the outset from an operating frequency or resonant frequency of the resonant circuit in which the respective induction heating coil is situated. The duration thereof can be in the above-mentioned range.

[0056] After a short time, a first ping having a specific level for the duration T is generated at all four induction heating coils. In the induction heating coil I1, the next individual ping with the same form is then only generated again after the interval of time A.sub.0.

[0057] In the second induction heating coil I2, a second ping with the same form is generated shortly after the first ping, namely at the interval of time A. A spell then elapses, namely (A.sub.0-T-A), until a first ping is generated again simultaneously with the first induction heating coil I1 and a second ping is then generated after a short interval of time A.

[0058] The pattern of the codings now continues in a similar manner for the third induction heating coil I3 and for the fourth induction heating coil I4, wherein three pings are generated in quick succession and four pings are generated in quick succession, each with the same interval A with respect to one another. The number of the induction heating coils emitting this coding can be directly read by counting these pings, possibly after the synchronization ping. This information can then be identified by the integrated circuit 40 and, in cooperation with the transmitting apparatus 42, can be transmitted as information to the external operating device 46. This transmitted information can then already be, for example, the evaluated number, that is to say 1 or I1 or the like.

[0059] In the pattern of codings according to FIG. 4, a first ping is generated with a duration T at all four induction heating coils I1 to I4 at the same time. After a time to after the first ping, a second ping is generated at the first induction heating coil I1. At an interval of time A later, the second ping is generated at the second induction heating coil I2 and, again at an interval of time A with respect to this, the second ping is generated at the third induction heating coil I3, etc. In this case, the interval of time to can correspond to the interval of time A, with the result that the number of the induction heating coil can be read out by counting these intervals of time until the coding pattern starts again.

[0060] FIG. 5 illustrates, for four induction heating coils I1 to I4, how a binary coding is transmitted as a statement regarding the respective induction heating coil after a first synchronization ping and a short interval of time. In this case, the first induction heating coil I1 transmits a 1 as binary code. The second induction heating coil I2 transmits a 2 as binary code etc.; each induction heating coil therefore transmits its own numeral or number as binary code. By arranging the respective pings in order in the grid illustrated using dotted lines for the binary code, this can be easily achieved and can be fundamentally carried out for a very large number of induction heating coils. Another code can also be used here instead of a binary code.

[0061] FIG. 6 illustrates a possible way of making a distinction in the case of four induction heating coils I1 to I4, in each case after a synchronization ping transmitted at the same time for all induction heating coils, using an amplitude of a subsequently transmitted ping. In this case, the amplitude gradually increases with the higher number of the induction heating coil. The pings of different amplitude are transmitted here at the same time, but they can naturally also be transmitted with a time delay.

[0062] FIG. 7 illustrates how very short pings can be used for four induction heating coils I1 to I4. In order to distinguish the individual induction heating coils by means of three transmitted pings, the interval between the second ping and the third ping is respectively varied. This can be easily seen from FIG. 7.

[0063] FIG. 8 illustrates, for eight induction heating coils I1 to I8, how, for two groups of induction heating coils, namely I1 to I4, on the one hand, and I5 to I8, on the other hand, a first ping is respectively transmitted at the same time using two induction heating coils. The interval of time to the subsequent, second ping, which varies from t1 to t8, reveals the number of the induction heating coil transmitting this coding.

[0064] On the basis of the transmitted coding of the respective induction heating coil, the number of the induction heating coil, above which the cooking vessel 27 is situated and the coding of which can be received in the heating area, can be communicated in the cooking vessel 27 to the external operating device 46, possibly likewise to the hob controller 18 as well. Precisely this cooking vessel 27 can then be reliably assigned to precisely this heating area of this induction heating coil, which is very important. Since the cooking vessel 27 also has the further sensors, an exactly running cooking program or the like can be carried out in a known manner.