Power supply system for an electrical load associated with a cooking utensil

Abstract

The invention relates to a power supply system for an electrical load associated with a cooking utensil (100), the power supply system comprising an electrical circuit comprising the load, which is formed when the cooking utensil (100) is placed on an electric hob (200) and which is electrically powered when a power signal is emitted in the hob (200). The electrical circuit comprises a first capacitive coupling (1.1) between the hob (200) and the cooking utensil (100), and a second capacitive coupling (1.2) between the cooking utensil (100) and a reference (1.3), the load being connected in series between both capacitive couplings (1.1, 1.2).

Description

TECHNICAL FIELD

[0001] The present invention relates to power supply systems for electrical loads associated with cooking utensils arranged on an electric hob, to cooking utensils comprising such loads, to cooking utensil handles comprising such loads, and to hobs adapted for such power supply systems.PRIOR ART

[0002] Cooking utensils such as pots, pans or frying pans, for example, are adapted to be placed on a hob for cooking or heating food.

[0003] In the case of wanting to add additional functionalities to the cooking utensil, such as a temperature display or others, this functionality can be accompanied by a battery to provide the necessary electrical power. Incorporating batteries in the cooking utensil has the disadvantage of requiring additional cost and space in the cooking utensil, which can increase the size of the cooking utensil, and also requires user action when a battery needs to be replaced with a new one once the first one has been discharged. Additionally, the arrangement of the batteries is sensitive to avoid excessive heating of the batteries, which makes their use on the cooking utensils (which are exposed to heat) more complex.

[0004] There is thus a need for a solution with which additional functionalities can be added to a cooking utensil in a simple way, without also having a negative impact on the user.DISCLOSURE OF THE INVENTION

[0005] The object of the invention is to provide a power supply system for an electrical load associated with a cooking utensil, a cooking utensil adapted for said power supply system, a removable handle for a cooking utensil, adapted for said power supply system and a cooking hob adapted for said power supply system, as defined in the claims.

[0006] A first aspect of the invention relates to a power supply system comprising an electrical circuit comprising the load, the electrical circuit being formed when the cooking utensil is arranged on a hob, and is the load being electrically powered when a power signal is emitted at the hob.

[0007] The electrical circuit comprises a first capacitive coupling between the hob and the cooking utensil, and a second capacitive coupling between the cooking utensil and a reference which can be ground or the hob itself (which will normally be grounded). The load is connected between the two capacitive couplings, preferably in series.

[0008] Thanks to the two capacitive couplings, the electrical circuit is a closed electrical circuit through which an electrical current flows when a power signal is emitted at the hob. As the load is connected between the two capacitive couplings, the load is electrically powered without the need to add additional power supplies to the cooking utensil, such as a battery for example, thus providing the cooking utensil with additional functionalities thanks to the power supply, in a simple and economical way, which are beneficial for the user of the cooking utensil.

[0009] Another aspect of the invention relates to a cooking utensil which is adapted for the power supply system of the first aspect, and which comprises the load.

[0010] Another aspect of the invention relates to a removable handle for a cooking utensil, which is adapted for the power supply system of the first aspect, and which comprises the load.

[0011] Another aspect of the invention relates to a cooking hob, which is adapted for the power supply system of the first aspect.

[0012] These and other advantages and features of the invention will become apparent in view of the figures and the detailed description of the invention.DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 shows an embodiment of a power supply system for an electrical load associated with a cooking utensil of the invention. Figure 2 shows an electrical circuit of an embodiment of the power supply system of the invention. Figure 3 shows an electrical circuit of another realisation of the power supply system of the invention. Figure 4 shows an embodiment of a removable handle according to the invention. Figure 5 shows another embodiment of a power supply system for an electrical load associated with a cooking utensil of the invention. DETAILED DISCLOSURE OF THE INVENTION

[0014] An aspect of the invention relates to a power supply system for at least one electrical load L associated with a cooking utensil 100. The cooking utensil 100 is adapted to hold food and is arranged on an electric cooking top 200 when heating or cooking such food is required as depicted in Figure 1.

[0015] The power supply system comprises an electrical circuit 1 comprising the load L, the electrical circuit 1 being formed when the cooking utensil 100 is arranged on a hob 200 and, preferably, when said hob 200 is electrically powered, and being electrically powered when a power supply signal is emitted at said hob 200 (by, for example, a power supply 201 of the hob 200).

[0016] The electrical circuit 1 comprises a first capacitive coupling 1.1 between the hob 200 and the cooking utensil 100, and a second capacitive coupling 1.2 between the cooking utensil 100 and a reference 1.3, the load L being connected in series between both capacitive couplings 1.1 and 1.2. Said reference 1.3 may be either ground or the hob 200 itself, such that the electrical circuit 1 is a closed circuit. Preferably it is the hob 200 itself that acts as reference 1.3, and in this case, it would have the same reference as the power supply 201 (which is normally connected to ground, such reference being ground).

[0017] This allows, when the electrical circuit 1 is electrically powered, an electrical current I to flow through the load L thanks to said capacitive couplings 1.1 and 1.2 (see Figures 2 and 3). The first capacitive coupling 1.1 enables the wireless transfer of electrical power from the hob 200 to the cooking utensil 100, and the second capacitive coupling 1.2 enables the return path for such electrical power.

[0018] When the hob 200 emits the power supply signal, thanks to the first capacitive coupling 1.1 and to this power supply signal, an electrical power supply is transferred to the electrical circuit 1.

[0019] The cooking utensil 100 comprises a metallic main body 101 as a container, the first capacitive coupling 1.1 of the electrical circuit 1 being produced between the main body 101 and the hob 200.

[0020] In some embodiments not depicted in the figures the load L may be comprised in the main body 101, while in other embodiments the load L may be comprised in other elements of the cooking utensil 100, such as a handle 102 (Figure 4) or a lid 103 (Figure 5). Additionally, the cooking utensil 100 may comprise an associated first load L on the handle 102 and a second load L on the lid 103.

[0021] In cases where there is a load L in the handle 102 and / or in the lid 103 of a cooking utensil 100, the electrical circuit 1 further comprises at least one energetic coupling 1.4 between the load L and said main body 101 (see figures 1 and 5). Said energetic coupling 1.4 may be an electrical coupling as depicted in figure 2 if there is an electrical contact between the load L and the main body 101, or a capacitive coupling as depicted in figure 3 in absence of said electrical connection.

[0022] In the case that the lid 103 comprised a load L, the electrical circuit 1 could comprise two energetic couplings 1.4 between the lid 103 and the main body 101, the load L being connected between both energetic couplings 1.4 (see figure 5).

[0023] A capacitive coupling, as in the case of capacitive couplings 1.1 and 1.2 for example, is defined between two conductive surfaces acting as a capacitor, and the value of the capacitive coupling depends on the area of these conductive surfaces facing each other (transfer area) and the distance between these conductive surfaces, as represented in the following equation: CF = A D ε , where: CF: capacitance (value of the capacitive coupling), A: transfer area between the two conductive surfaces, D: distance between the two conductive surfaces, and ε: dielectric permissibility of the medium.

[0024] Likewise, the capacitive reactance of a capacitive coupling is determined by the following equation: RF = 1 CF ∗ 2 πf ′ where: RF: capacitive reactance, CF: capacitance (value of the capacitive coupling), and f: frequency of the power supply signal.

[0025] The higher the capacitive reactance of a capacitive coupling, the lower the electrical power that can be transferred through it. In the case of the second capacitive coupling 1.2, the distance D with respect to the reference 1.3 may have a different value depending on the point from which the second capacitive coupling 1.2 is generated, and may depend on aspects such as, for example, the height of the cooking utensil 100.

[0026] Thus, the higher the frequency of the power supply signal, the more certain it is that electrical circuit 1 is supplied with sufficient electrical power (since the electrical power transfer capacity is increased, see equation 2).

[0027] The load L may comprise such electronic elements and / or devices that are considered appropriate, such as for example lighting devices or a display. In some embodiments, the load L comprises a wireless communication module and the hob 200 comprises a wireless communication module, such communication modules being configured to communicate with each other.

[0028] In some embodiments in which both the load L and the hob 200 comprise a communication module, the load L also comprises an identification (in the form of a code for example) associated with the corresponding cooking utensil 100, said identification being transmitted from the cooking utensil 100 to the hob 200 thanks to said communication modules. This means that in hobs 200 with more than one heater, it is possible to know at all times on which heater said cooking utensil 100 is located, regardless of whether it changes its position, the hob 200 itself being able to adapt, for example, a cooking programme associated with the same cooking utensil 100 to the corresponding heater regardless of whether said cooking utensil 100 changes its location on the hob 200. Logically, this will be the case when the corresponding heater is powered, since it is when the load L is powered.

[0029] In some embodiments, the load L comprises a supercapacitor, such that when the hob 200 outputs the power supply signal, the supercapacitor can be charged and can thus operate as a battery when required (when the hob 200 stops outputting the power supply signal for example).

[0030] The electrical circuit 1 of the power supply system preferably comprises a metallic foil 400 depicted by way of example in Figure 4, the second capacitive coupling 1.2 being generated between said metallic foil 400 and the reference 1.3 and said metallic foil 400 may comprise any shape. The embodiment of such a metallic foil 400 provides the second capacitive coupling 1.2 as required and where required.

[0031] The metal foil 400 is connected to the load L and associated with the cooking utensil 100. The load L and the metal foil 400 may be arranged in the cooking utensil 100. In some embodiments both the load L and the metal foil 400 are arranged in the main body 101 but they could also be in the handle 102 and / or the lid 103 associated with the cooking utensil 100.

[0032] The hobs 200 may be electric hobs 200 where the heat for heating the cooking utensil 100 is generated from electricity, or they may be gas hobs 200 where the heat for heating the cooking utensil 100 is generated from gas.

[0033] The electric hobs 200 comprise a power supply 201, and at least one heater and an electrical element 202 associated with said heater, the electrical element 202 being configured to transfer heat to the cooking utensil 100 when said cooking utensil 100 is disposed on said heater and when electrically powered. The power supply 201 is configured to supply the electrical element 202 with the power supply signal, so as to cause electrical power to be transferred to the cooking utensil 100 via the first capacitive coupling 1.1. The electrical element 202 may be an induction coil in the case of an induction hob, or a resistor in the case of a glass ceramic hob.

[0034] The power supply 201 is configured to electrically power the electrical element 202 with a heating signal to transfer heat to the cooking utensil 100. In some embodiments, the heating signal is the power supply signal. This may be the case for an induction hob 200, where the electrical element 202 is a coil and the heating signal has a frequency of around 40 kHz. In other embodiments, the power supply signal is a signal in addition to the heating signal. This may be the case in glass ceramic hobs 200, where the electrical element 202 is a resistor and the heating signal has a frequency equal to the mains frequency (50 Hz in Europe). In this case, to ensure that the load L is electrically powered regardless of the type of cooking utensil 100 used, an additional signal as a power signal is preferably used, preferably with a frequency of at least 20 kHz. Although this additional signal solution is particularly advantageous in the case of a glass ceramic hob, and although at first glance it might not seem necessary, an additional signal could also be used as a power supply signal with the required or desired frequency for induction hobs 200.

[0035] In the case of a gas hob 200, the gas hob 200 comprises a power supply 201 for generating a power signal and a metal element connected to the power supply 201, the first capacitive coupling 1.1 being generated between said metal element and the cooking utensil 100 when the power supply signal is generated. In this case, the power supply 201 generates a power supply signal whose function is to electrically power the electrical circuit 1, since the heating function uses gas as fuel (from which a flame is generated to provide heat).

[0036] Another aspect of the invention relates to a cooking utensil 100 adapted for a power supply system as described, in any of its embodiments and / or configurations, and comprising the load L. The cooking utensil 100 comprises a main body 100 and may comprise a handle 102 and / or a lid 103, wherein the load L may be in the handle 102, in the lid 103 and / or in the main body 101. The cooking utensil 100 may comprise the metal foil 400 where appropriate, as previously described, and said metal foil 400 is preferably in the handle 102 when the load L is in the handle 102, and in the lid 103 when said load L is in the lid 103, although other combinations could also be possible, such as for example the load L being in the lid 103 and the metal foil 400 in the handle 102.

[0037] Another aspect of the invention relates to a removable handle 102 for a cooking utensil 100, such as that depicted by way of example in figure 5, which is adapted for a power supply system as described, in any of its embodiments and / or configurations, and which comprises the load L and, preferably, a metal foil 400 as described.

[0038] Another aspect of the invention relates to an electric or gas hob 200 adapted for a power supply system as described, in any of its embodiments and / or configurations.

[0039] In some embodiments, said hob 200 comprises a power supply 201 and at least one heater and an electrical element 202 associated with said heater, the electrical element 202 being configured to transfer heat to the cooking utensil 100 when said cooking utensil 100 is disposed over said heater. The power supply 201 is configured to supply the electrical element 1 with a heating signal. The various alternatives described above for the heating signal and the power supply signal are also valid for the proposed hob 200. Said hob 200 may preferably be an induction hob or a glass ceramic hob. In other embodiments, said hob 200 is a gas hob as previously described.

Claims

1. Power supply system for an electrical load (L) associated with a cooking utensil (100), the power supply system comprising an electrical circuit (1) comprising the load (L), the electrical circuit (1) being formed when the cooking utensil (100) is arranged on a cooking hob (200) and the load (L) being electrically powered when a power signal is emitted in said hob (200), wherein the electrical circuit (1) comprises a first capacitive coupling (1.1) between the hob (200) and the cooking utensil (100), and a second capacitive coupling (1.2) between the cooking utensil (100) and a reference (1.3), the load (L) being connected in series between both capacitive couplings (1.1, 1.2).

2. Power supply system according to claim 1, wherein the cooking utensil (100) comprises a main body (101) made of metal as a container, wherein the first capacitive coupling (1.1) of the electrical circuit (1) being generated between said main body (101) and the hob (200), and said electrical circuit (1) comprising an energetic coupling (1.4) between the load (L) and said main body (101), said energetic coupling (1.4) being an electrical coupling if an electrical contact is produced between the load (L) and the main body (101), or a capacitive coupling in absence of said electrical contact.

3. Power supply system according to claim 1 or 2, wherein the reference (1.3) used to generate the second capacitive coupling (1.2) is ground or the hob (200).

4. Power system according to any of claims 1 to 3, wherein the load (L) comprises a wireless communication module, and the hob (200) comprises a wireless communication module, said communication modules being configured to communicate with each other.

5. Power system according to claim 4, wherein the load (L) further comprises an identification associated with the cooking utensil (100), the wireless communication module of the load (L) being configured to transmit said identification to the hob (200).

6. Power supply system according to any of claims 1 to 5, comprising a metal foil (400) connected to the load (L) and associated with the cooking utensil (100), the second capacitive coupling (1.2) being generated between said metal foil (400) and the reference (1.3).

7. Power supply system according to any of claims 1 to 6, wherein the hob (200) comprises a power supply (201) and at least one heat source and an electrical element (202) associated with said heat source, the electrical element (202) being configured to transfer heat to the cooking utensil (100) when said cooking utensil (100) is disposed over said heat source, and the power supply (201) being configured to power the electrical element (1) with the power signal.

8. Power supply system according to claim 7, wherein the power supply (201) is configured to supply the electrical element (202) with a heating signal to transfer heat to the cooking utensil (100), said heating signal being the power supply signal.

9. Power supply system according to claim 7, wherein the power supply (201) is configured to supply the electrical element (202) with a heating signal to transfer heat to the cooking utensil (100), the power supply signal being an additional signal to said heating signal.

10. Cooking utensil adapted for a power supply system according to any of claims 1 to 9, comprising the electrical load (L).

11. Cooking utensil according to claim 10, comprising a handle (102) where the load (L) is arranged, or comprising a lid (103) where the load (L) is arranged.

12. Removable handle for a cooking utensil, which is adapted for a power supply system according to any of claims 1 to 9, the handle (102) comprising the electrical load (L).

13. Cooking hob adapted for a power supply system according to any of claims 1 to 6, comprising a power supply (201), at least one heater and an electrical element (202) associated with said heater, the electrical element (202) being configured to transfer heat to the cooking utensil (100) when said cooking utensil (100) is positioned over said heater, and the power supply (201) being configured to supply the electrical element (202) with a heating signal, the power signal being a signal in addition to the heating signal.

14. Cooking hob adapted for a power supply system according to any of claims 1 to 6, comprising a power supply (201), at least one heater and a metallic element associated with said heater and connected to the power supply (201), the metallic element being configured for the first capacitive coupling (1.1) being generated between said metallic element and a cooking utensil (100) placed on said associated heater, and the power supply unit (201) is configured to supply the metallic element with the power signal.

15. Cooking hob according to claim 14, wherein the hob (202) is a gas hob.

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