Induction hob plate

Abstract

Induction cooktop plate. The invention relates, in the field of cookware or containers for induction cooktops, to an induction cooktop plate. The induction cooktop plate (A) according to the invention has a base (F) comprising a layer of magnetic material (F1) and raised above its lowest point, that of the base (B), corresponding to the location of the glass-ceramic plate (V). The base (B) of the plate (A) comprises magnetic material (M), such as magnetic stainless steel or ferrite, distributed between a central portion (MC) and a peripheral portion (MP). The plate (A) has a rim (R) made of non-magnetic material, which serves as a gripping means (MP).In terms of use, the plate (A) according to the invention has the advantage, after heating its contents, of being able to be placed on a table without the need for a trivet, particularly for a single plate or multiple plates. Figure to be published with the abbreviation: Fig. 5.

Description

Title of the invention: Plate for induction hob

[0001] FIELD OF THE INVENTION TO WHICH THE INVENTION RELATES

[0002] The invention relates to the field of kitchen utensils or containers for induction hobs. PREVIOUS ART

[0003] When preparing a dish in a microwave oven, the electrical energy consumed is essentially devoted to cooking the liquid or solid food contained in a container. In this case, the electrical energy consumed is not used directly to heat the container or the oven itself.

[0004] It is even possible to prepare a dish on a plate that will not be heated by the microwave and to present the dish as is on a table.

[0005] In the case of a cooking appliance comprising one or more induction plates, heat is created by the magnetic field which heats the magnetic elements such as magnetic stainless steel present in the cooking utensil or container.

[0006] As shown [Fig. 1], the bottom (F) of the cooking utensil or container, in this case a frying pan, comprises several layers. The first layer (F1) is a layer of magnetic stainless steel which will create the heat, the second layer (F2) is a layer of aluminum which will diffuse the heat created, the third layer (F3) will be in contact with the food and will be made of non-magnetic stainless steel.

[0007] Conventionally; the wall (P) is metallic and the utensil (U) has a gripping means (MP) such as a handle.

[0008] The induction coil (BI) will generate an electromagnetic field which will heat the magnetic elements by eddy current, in this case the layer (Fl).

[0009] In doing so, heating of this layer (Fl) will be transmitted not only via its upper face to the food contained in the utensil (U) but also via its lower face to the vitroceramic plate (V) which usually covers the induction cooking plate.

[0010] Compared to cooking in a microwave oven, the induction cooking solution devotes, in addition to the energy directly devoted to heating the food, energy to heating the cooking utensil or container but also energy to heating the vitroceramic plate (V) which supports the cooking utensil or container (U).

[0011] Furthermore, once the contents of the cooking utensil or container have been heated, the bottom of the cooking utensil or container is too hot for it to be placed on a table without a trivet.

[0012] It is of course possible to serve the dish directly in the pan placed on the table on a trivet and to eat from the pan for one person alone or to divide the dish into different plates for several people.

[0013] The present invention aims to reduce the energy loss of the cooking plate used to unnecessarily heat the glass-ceramic plate which supports the cooking utensil or container and to be able to place the prepared dish directly on the table when serving it.

[0014] BRIEF DESCRIPTION OF THE INVENTION

[0015] The kitchen utensil or container for an induction hob according to the invention is a plate which has a bottom which comprises a layer of magnetic material and which is raised relative to its lowest level, that of the base, corresponding to the location of the glass-ceramic hob.

[0016] The bottom (F) is raised by several millimeters.

[0017] Preferably, the surface area of ​​the base represents at most 25% of the surface area of ​​the bottom.

[0018] According to a first embodiment, the base comprises a material which has no magnetic properties and which is thermally insulating.

[0019] According to a first embodiment, the base comprises a material which has no magnetic properties and which is ceramic.

[0020] According to a third embodiment, the base comprises a magnetic material, such as martensitic stainless steel, grade 440C.

[0021] According to a fourth embodiment, the base comprises a soft magnetic material.

[0022] Preferably, to avoid heat transmission, the soft magnetic material of the base is spaced from the bottom by an air gap.

[0023] Advantageously, the soft magnetic material comprises ferrite.

[0024] Preferably, the plate has a rim made of non-magnetic material which is a gripping means.

[0025] In terms of use, the kitchen utensil or container according to the invention has the advantage of being able to be placed on a table after heating its contents without having to use a trivet. Brief description of the drawings

[0026] Other characteristics and advantages of the invention will appear on reading the detailed description which follows, for the understanding of which reference will be made to the attached drawings.

[0027] [Fig. 1] shows a pan for induction hob in a classic configuration.

[0028] [Fig.2] shows a plate for an induction hob according to the invention where the rim and base are made of plastic material.

[0029] [Fig.3] shows a plate for an induction hob according to the invention where the rim and the base are made of glass-ceramic material.

[0030] [Fig.4] shows a plate for an induction hob according to the invention where the base has magnetic stainless steel.

[0031] [Fig.5] shows a plate for an induction hob according to the invention where the base comprises soft magnetic material. DETAILED DESCRIPTION OF THE INVENTION

[0032] The kitchen utensil or container (U) for an induction hob (PC) according to the invention is a plate (A) which has a bottom (F) which comprises a layer (Fl) of magnetic material and which is raised relative to its lowest level, that of the base (B), corresponding to the location of the vitroceramic hob (V).

[0033] The bottom (F) is raised by several millimeters.

[0034] The base (B) may correspond to the entire surface of the bottom of the kitchen utensil or container (U) which makes it possible to protect the user from the lower face of the bottom (F) which may be hot.

[0035] Preferably, the surface area of ​​the base (B) represents at most 25% of the surface area of ​​the bottom (F) to limit the heat exchange with the glass-ceramic plate (V).

[0036] According to a first illustrated embodiment [Fig.2], the rim (R) and the base (B) are made of a thermally insulating material which has no magnetic properties.

[0037] This material can be a plastic material or silicone compatible with a temperature level of the order of 200°C to 250°C, materials already used in current kitchen utensils, in particular in the form of high temperature seals.

[0038] According to a second illustrated embodiment [Fig.3], the rim (R) and the base (B) are made of ceramic like conventional plates. To prevent the heat from the bottom (F) from being directly transmitted to the rim (R) and the base (B), a thermally insulating joint (I) is added between the bottom (F) and the rest of the plate (A). This joint (I) can also act as an expansion joint to absorb the different expansion effects between the bottom (F) and the rest of the plate (A). From this point of view, it is advantageous for the material to be glass-ceramic material, the physical characteristics of which have already been proven in the field of cooking plates (PC).

[0039] To reduce the added air gap effect of several millimeters between the induction coil (BI) and the layer (Fl), the base (B) comprises magnetic material (M) as illustrated [Fig.4] and [Fig.5].

[0040] This magnetic material (M) is preferably divided into two parts (MC) and (MP).

[0041] The first part (MC) is a central part used to channel the magnetic flux from the middle of the induction coil. Typically this central part is inscribed in a circle of diameter 5 cm, dimension of the central empty space of an induction coil.

[0042] The second part (MP) is a peripheral part which will also channel the peripheral magnetic flux of the induction coil (BI). Its thickness will be a few millimeters.

[0043] In the third embodiment illustrated [Fig. 4], the magnetic material (M) is a magnetic material of the type of that of the layer (Fl). It can for example be made of a martensitic stainless steel, grade 440C

[0044] If the solution is simple to implement, it has the disadvantage that the base (B) comprising a magnetic material will heat up and lead to a small loss of electrical energy.

[0045] It is preferable as illustrated that these magnetic elements which will heat are set back from the lower level of the base (B).

[0046] On the other hand, this variant remains compatible with a temperature measurement in the center of the kitchen utensil or container (U) by the cooking plate (PC) due to the presence of the central part (MC).

[0047] According to a fourth embodiment illustrated [Fig.5], the base (B) comprises a soft magnetic material in place of the previous magnetic material. This soft magnetic material will channel the magnetic flux without heating linked to eddy currents.

[0048] Preferably, to avoid heat transmission, the soft magnetic material of the base (B) is spaced from the bottom (F) by an air gap.

[0049] These soft magnetic materials are those used in transformers.

[0050] Advantageously, the soft magnetic material comprises ferrite. This may be molded ferrite which may be brittle or ferrite embedded in a plastic material such as plastoferrite.

[0051] Preferably, the plate has a rim made of non-magnetic material which is a gripping means.

[0052] Indeed, the plate (A) according to the invention does not have any gripping means (MP) such as the handle of a frying pan or the ears of a saucepan, which is advantageous for placing the kitchen utensil on the table.

[0053] On the other hand, during cooking on the hob, the plate not having a handle or ears, it is advantageous that the edge (R) of the plate (A) is not heated by the induction of the hob (PC) so as to be able to directly handle the plate during cooking without burning yourself.

[0054] In terms of use, the plate (A) according to the invention has the advantage of being able to be placed on a table after heating its contents without having to use a trivet.

[0055] In the case of a meal for one person, this has the advantage of being able to prepare the dish directly on the plate on the hob (PC) and eat it directly on the plate without additional dishes,

[0056] In the case of a meal for several people, this has the advantage of being able to simultaneously prepare several plates on each location of a multi-location cooking plate (PC), usually up to four. Industrial application

[0057] In terms of industrial application, the invention applies to plates for induction hobs.

[0058] The present invention is in no way limited to the embodiments described and shown, but those skilled in the art will be able to provide any variation in accordance with its spirit for a range of products.

Claims

Claims

1. Plate (A) for induction hob (PC) characterized by the fact that its base (F) comprises a layer (Fl) of magnetic material and that this base (F) is raised relative to its lowest level, that of the base (B), corresponding to the location of the vitroceramic plate (V), and the fact that the base (B) comprises a magnetic material (M) distributed between a central part (BC) and a peripheral part (BP).

2. Plate (A) according to claim 1 characterized in that the magnetic material (M) is martensitic stainless steel, grade 440C.

3. Plate (A) of claim 1 characterized in that the base (B) comprises a soft magnetic material (M).

4. Plate (A) according to claim 3 characterized in that the soft magnetic material (M) of the base (B) is spaced from the bottom (F) by an air gap.

5. Plate (A) according to any one of claims 3 to 4, characterized in that the soft magnetic material (M) comprises ferrite.

6. Plate (A) according to any one of claims 1 to 5 characterized in that the plate (A) has a rim (R) made of non-magnetic material which is a gripping means (MP).

7. Use of the plate (A) characterized by the fact that the plate (A) according to any one of claims 1 to 6, after having heated its contents on the induction cooking plate (PC), is directly placed on a table with its heated contents without using a trivet.

Images