Energy transfer cooking device accessory, method of manufacturing an energy transfer cooking device accessory and cooking device

Abstract

An energy transfer cooking device accessory is described which includes a plastically deformed metal sheet (and a transformer-like power transfer unit which has a primary circuit and a secondary circuit. The plastically deformed metal sheet is arranged between said primary circuit and said secondary circuit. Simultaneously said plastically deformed metal sheet forms a magnetically permeable coupling point for said primary circuit and said secondary circuit, so that a magnetic flux from said primary circuit to said secondary circuit via said plastically deformed metal sheet is guaranteed. Furthermore, a method of manufacturing an energy transfer cooking device accessory and a cooking device are described.

Claims

1. An energy transfer cooking device accessory, comprising a plastically deformed metal sheet and a transformer-like power transfer unit, which has a primary circuit and a secondary circuit, wherein the plastically deformed metal sheet has a deformation region which has a locally considerably increased magnetic permeability by comparison with the remainder of the metal sheet in the non-plastically deformed region so that the metal sheet in the local deformation region permits higher magnetic flux as the deformation region is magnetically permeable, said plastically deformed metal sheet being arranged between said primary circuit and said secondary circuit and forms a magnetically permeable coupling point for said primary circuit and said secondary circuit, so that magnetic flux from said primary circuit to said secondary circuit via said plastically deformed metal sheet is guaranteed.

2. The cooking device accessory according to claim 1, wherein said metal sheet is a stainless steel sheet.

3. The cooking device accessory according to claim 1, wherein said metal sheet has a smooth surface.

4. The cooking device accessory according to claim 1, wherein said metal sheet is plastically deformed by pressing.

5. The cooking device accessory according to claim 4, wherein said metal sheet is plastically deformed with a press ram formed as a matrix.

6. A cooking accessory with an energy transfer cooking device accessory and a heating region, which is electrically coupled to said cooking device accessory, said energy transfer cooking device accessory comprising a plastically deformed metal sheet and a transformer-like power transfer unit, which has a primary circuit and a secondary circuit, wherein the plastically deformed metal sheet has a deformation region which has a locally considerably increased magnetic permeability by comparison with the remainder of the metal sheet in the non-plastically deformed region so that the metal sheet in the local deformation region permits higher magnetic flux as the deformation region is magnetically permeable, said plastically deformed metal sheet being arranged between said primary circuit and said secondary circuit and forms a magnetically permeable coupling point for said primary circuit and said secondary circuit, so that magnetic flux from said primary circuit to said secondary circuit via said plastically deformed metal sheet is guaranteed.

7. The cooking accessory according to claim 6, wherein said cooking accessory is a smoker device.

8. A method of manufacturing an energy transfer cooking device accessory according to claim 1, wherein a metal sheet and a transformer-like power transfer unit are provided with a primary circuit and a secondary circuit, said metal sheet being plastically deformed, so that said metal sheet forms a magnetically permeable coupling point for said primary circuit and said secondary circuit of said transformer-like power transfer unit, said primary circuit being arranged on one face of said plastically deformed metal sheet and said secondary circuit on the opposing face of said plastically deformed metal sheet.

9. The method according to claim 8, wherein said metal sheet is plastically deformed by pressing.

10. The method according to claim 9, wherein said metal sheet is plastically deformed with a press ram provided as a matrix.

11. The method according to claim 9, wherein said metal sheet is pressed at least twice, said metal sheet at least in said first pressing process being pressed with a matrix formed as a press ram.

12. The method according to claim 11, wherein said press ram has a surface which results in high metal deforming.

13. The method according to claim 8, wherein said metal sheet is plastically deformed by heating.

14. The method according to claim 13, wherein said metal sheet is tempered or heated and subsequently slowly cooled.

15. The method according to claim 8, wherein said metal sheet is plastically deformed across its entire thickness, resulting in a continuously deformed metal sheet portion.

16. A cooking device with a cooking chamber and a cooking chamber wall, at least one portion of said cooking chamber wall forming said plastically deformed metal sheet of the energy transfer cooking device accessory according to claim 1, so that said portion of said cooking chamber wall forms a magnetically permeable coupling point for said primary circuit and said secondary circuit of the transformer-like power transfer unit.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Additional advantages and properties of the invention are outlined in the following description and by the drawing FIG. 1 to which reference is made. The single figure is a schematic representation of a cooking device according to the invention with an energy transfer cooking device accessory according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

(2) In FIG. 1, a cooking device 10 is partially shown in a schematic manner because only a portion of the cooking chamber 12 is shown.

(3) The cooking chamber 12 is bounded in the portion shown, amongst others, by a cooking chamber wall 14 formed by a metal sheet 16, particularly a stainless steel sheet (material 1.4301).

(4) The cooking chamber wall 14 or rather the metal sheet 16 has been plastically deformed locally during manufacture so that a local deformation region 18 has formed. The deformation region 18 has a higher magnetic permeability than the remainder of the cooking chamber wall 14 or rather the metal sheet 16, although the remainder of the cooking chamber wall 14 and the deformation region 18 consists of the same material.

(5) This is because the plastic deformation of the metal sheet 16 in the local deformation region 18 has caused the grain structure in the material of the metal sheet 16 to be altered as compared with a flat metal sheet. Correspondingly the deformation region 18 establishes a magnetically permeable coupling point 20 which permits magnetic flux through the otherwise magnetically non-conductive cooking chamber wall 14.

(6) The magnetic conductivity has therefore been achieved by a deformation process of the cooking chamber wall 14 or rather the metal sheet 16 as no other material was used to establish the magnetically permeable coupling point 20.

(7) The cooking device 10 also comprises a transformer-like power transfer unit 22 which is connected at the coupling point 20. The transformer-like power transfer unit 22 serves the cordless or wireless energy transfer from one side of the cooking chamber wall 14 to the other side of the cooking chamber wall 14, by which means wireless energy transfer into the cooking chamber 12 is possible for example. A cable ducting or similar is therefore not required.

(8) The transformer-like power transfer unit 22 has a primary circuit 24 and a secondary circuit 26 wherein, in the embodiment shown, the primary circuit 24 is arranged outside the cooking chamber 12 and the secondary circuit 26 is arranged inside the cooking chamber 12. The primary and the secondary circuit 24, 26 each have a primary and secondary coil 28, 30 respectively wherein the number of turns may differ.

(9) FIG. 1 further shows that the transformer-like power transfer unit 22 has a connected heating region 32, to which a cooking sheet 34, for example, is allocated, which is depicted by broken lines. Correspondingly the energy transferred wirelessly into the cooking chamber 12 via the transformer-like power transfer unit 22 can be used to warm the cooking sheet 34, by which means an electrically heated cooking surface can be arranged in the cooking chamber 12 without requiring a cable ducting to be insulated through the cooking chamber wall 14.

(10) The transformer-like power transfer unit 22 and the deformation region 18 of the metal sheet 16 or rather the cooking chamber wall 14, namely a plastically deformed metal sheet portion, together form an energy transfer cooking device accessory 36.

(11) The energy transfer cooking device accessory 36 may also form a cooking accessory 38 together with the heating region 32 and/or the metal sheet 34.

(12) For example, the cooking accessory 38 is a smoker device via which food placed in the cooking chamber 12 can be smoked. The smoker device encompasses the heating region 32, which is coupled electrically to the energy transfer cooking device accessory 36. Via the electrical power provided wirelessly a smoker material placed inside a receiving chamber of the cooking accessory 38 or of the smoker device may be heated, so that it emits corresponding aromas in order to smoke the food in the cooking chamber 12.

(13) Alternatively to the cooking sheet 34 with the heating region 32, another cooking accessory can be provided which requires electrical power and can be coupled to the energy transfer cooking device accessory 36, for example a temperature probe, in particular a core temperature probe.

(14) In general the power transfer unit 22 is like a transformer because a free space distance, in other words a magnetically non-conducting path, between the primary and the secondary circuit 24, 26 is avoided. This is because the local deformation region 18 is magnetically permeable, particularly in a similar manner to the ferrite or iron material which at least partially provides the primary and/or secondary circuit 24, 26.

(15) Accordingly, the ferrite and/or iron material of the primary and secondary circuits 24, 26, together with the magnetically permeable deformation region 18 or rather the coupling point 20 provided thereby establishes a multi-partite core 40 of the transformer-like power transfer unit 22 as is normal in the case of a transformer.

(16) Gaps or magnetically non-permeable materials between the respective coils 28, 30 of the primary and of the secondary circuit 24, 26 are thus avoided, for which reason this is referred to as a transformer-like power transfer unit 22, which transfers the energy wirelessly from the one side of the cooking chamber wall 14 to the other side of the cooking chamber wall 14, particularly into the cooking chamber 12.

(17) This is a non-resonant power or energy transfer, which is why the coils 28, 30 also do not have to be matched to one another in respect of their resonant frequencies. The efforts of manufacture are therefore considerably reduced.

(18) The local deformation region 18 may be manufactured in particular by means of a pressing process in which the metal sheet 16 is deformed. This ensures that the material thickness of the metal sheet 16 only changes slightly in the local deformation region 18.

(19) In addition, it may be envisaged that the metal sheet 16 is subsequently treated thermally, being exposed for example to a moderate rise in temperature (tempering), in order to reduce tensions in the metal sheet 16 which have been introduced as a result of the deformation process.

(20) Alternatively or additionally, the metal sheet 16 can be heated strongly and then cooled slowly in order to introduce an additional ferritic phase into the austenitic material, resulting in an additional increase in the magnetic permeability of the metal sheet 16 in the local deformation region 18.

(21) The metal sheet 16 is plastically deformed through its entire thickness, particularly in the deformation region 18, resulting in a continuously deformed metal sheet portion which represents the local deformation region 18. Correspondingly the deformation process is not an embossing operation, in which only the material in a particular region is compressed, in particular on the corresponding surface.

(22) When deforming the metal sheet 16, the metal sheet 16 is deformed such that the resulting surface of the metal sheet 16 after the final deforming step is smooth and flat. A rough surface of the metal sheet 16 in the deformation region 18 would result in a partially strong bundling of the magnetic field lines during energy transfer, by which means the saturation magnetization could be exceeded locally, which has a negative impact on power transfer. In addition, such a surface is also more hygienic since it is easier to clean.

(23) In general, the metal sheet 16 can be pressed during deforming wherein a press ram formed as a matrix is used, for example.

(24) In particular it is then envisaged that the metal sheet 16 is pressed twice, with the metal sheet 16 initially being pressed with a press ram which has a surface that results in high material deforming. By this means the magnetic permeability of the metal sheet 16 in the local deformation region 18 can be increased greatly.

(25) Because of the high material deforming, however, the metal sheet 16 in the deformation region 18 has an uneven and/or rough surface which is a disadvantage, on the one hand, in terms of cleaning, as well as in terms of wireless energy transfer, as has already been described. Therefore the metal sheet 16 pressed with such a press ram is pressed again in order to obtain a surface as smooth as possible.

(26) Accordingly wireless energy transfer is created by simple means, being effected non-resonantly and inductively, and the transferred energy can be used by a cooking accessory by simple means.

(27) As already explained, the heating region 32 can be associated with a cooking accessory 38 provided as a smoker device, so that the smoker device encloses the heating region 32 and the energy transfer cooking device accessory 36, the two of which are coupled to one another. The energy transfer cooking device accessory 36 ensures that wireless or cordless energy transfer is enabled via a cooking chamber wall 14 of the cooking device 10, in that the cooking accessory 38 is used, in other words the smoker device. The smoker device normally comprises a housing, which is not shown in detail, which surrounds a receiving chamber for smoker materials, for example smoker fuel. The heating region 32 then warms the smoker materials accommodated in the receiving chamber, so that they emit a corresponding smoked aroma. The smoker device placed in the cooking chamber 12, whose energy supply is effected wirelessly via the energy transfer cooking device accessory 36, accordingly emits the smoked aromas in the cooking chamber 12 of the cooking device 10, by which means the food is smoked.

(28) The energy transferred wirelessly via the energy transfer cooking device accessory 36 is utilised correspondingly in the heating region 32 in order to smoke the food in the cooking chamber 12. A portion of the cooking chamber wall 14 may constitute the magnetically permeable coupling point 20 via which the wireless energy transfer is possible by correspondingly efficient means.