Cooking Utensil Comprising An Aluminum Shell

Abstract

A cooking utensil having a metal shell includes a bottom wall and a side wall rising up around the bottom wall, the bottom wall having an inner face configured to cook food and an outer face configured for placing in proximity to a source of heat, wherein the shell is a deep-drawn or flow-formed 6082 aluminum alloy sheet from the 6000 series, or the 5083 alloy from the 5000 series, and a method of manufacturing same.

Claims

1-18. (canceled)

19. A cooking utensil comprising a metal shell having a bottom wall and a side wall rising up around the bottom wall, said bottom wall having an inner face configured for cooking food and an outer face configured to be placed in proximity to a source of heat, a metal insert mounted directly onto the outer face, the metal insert produced from a ferromagnetic material, in such a way that the cooking utensil is compatible with induction heating, said shell comprising a deep-drawn or flow-formed aluminum alloy sheet from the 6000 series, wherein said shell is a 6082 aluminum alloy sheet, and wherein the bottom wall has a thickness at least twice that of the side wall.

20. The cooking utensil according to claim 19, wherein the bottom wall has a thickness at least twice of that of the side wall.

21. The cooking utensil according to claim 19, wherein the bottom wall has a thickness at least 2.5 times greater than that of the side wall.

22. The cooking utensil according to claim 19, wherein the bottom wall has a thickness less than or equal to 15 times that of the side wall.

23. The cooking utensil according to claim 19, wherein the bottom wall has a thickness less than or equal to 13.5 times that of the side wall.

24. The cooking utensil according to claim 19, wherein the inner face is partially or entirely coated with a PTFE, or ceramic, or sol-gel coating.

25. The cooking utensil according to claim 19, wherein the outer face is partially or entirely coated with an enamel, or PTFE, or ceramic, or sol-gel coating.

26. The cooking utensil according to claim 19, wherein the metal insert is formed by a grid.

27. The cooking utensil according to claim 19, wherein the shell has a diameter/height ratio of less than 0.5.

28. The cooking utensil according to claim 19, wherein the shell has a diameter/height ratio of less than 0.3.

29. The cooking utensil according to claim 19, wherein the shell has a diameter/height ratio of between 0.5 and 0.1.

30. The cooking utensil according to claim 19, wherein the shell has a diameter/height ratio of between 0.3 and 0.1.

31. A cooking utensil comprising a metal shell having a bottom wall and a side wall rising up around the bottom wall, said bottom wall having an inner face configured for cooking food and an outer face configured to be placed in proximity to a source of heat, a metal insert mounted directly onto the outer face, the metal insert produced from a ferromagnetic material, in such a way that the cooking utensil is compatible with induction heating, said shell comprising a deep-drawn or flow-formed aluminum alloy sheet from the 5000 series, wherein said shell is a 5083 aluminum alloy sheet, and wherein the bottom wall has a thickness at least twice that of the side wall.

32. The cooking utensil according to claim 31, wherein the bottom wall has a thickness at least twice that of the side wall.

33. The cooking utensil according to claim 31, wherein the bottom wall has a thickness at least 2.5 times greater than that of the side wall.

34. The cooking utensil according to claim 31, wherein the bottom wall has a thickness less than or equal to 15 times that of the side wall).

35. The cooking utensil according to claim 31, wherein the bottom wall has a thickness less than or equal to 13.5 times that of the side wall.

36. The cooking utensil according to claim 31, wherein the inner face is partially or entirely coated with a PTFE, or ceramic, or sol-gel coating.

37. The cooking utensil according to claim 31, wherein the outer face is partially or entirely coated with an enamel, or PTFE, or ceramic, or sol-gel coating.

38. The cooking utensil according to claim 31, wherein the metal insert is formed by a grid.

39. The cooking utensil according to claim 31, wherein the shell has a diameter/height ratio of less than 0.5.

40. The cooking utensil according to claim 31, wherein the shell has a diameter/height ratio of less than 0.3.

41. The cooking utensil according to claim 31, wherein the shell has a diameter/height ratio of between 0.5 and 0.1.

42. The cooking utensil according to claim 31, wherein the shell has a diameter/height ratio of between 0.3 and 0.1

43. A 6082 aluminum alloy from the 6000 series configured for manufacturing the metal shell of a cooking utensil according to claim 19.

44. A 5083 aluminum alloy from the 5000 series configured for manufacturing the metal shell of a cooking utensil according to claim 31.

45. A method of manufacturing a cooking utensil according to claim 19, comprising the following steps: furnishing a 6082 aluminum alloy sheet from the 6000 series; optionally mounting a metal insert onto the outer face; deep drawing or flow forming said sheet into the shell shape; optionally applying a PTFE, or ceramic, or sol-gel coating partially or entirely over the inner face; and optionally applying an enamel, PTFE, ceramic, or sol-gel coating partially or entirely over the outer face.

46. A method of manufacturing a cooking utensil according to claim 20, comprising: furnishing a 5083 aluminum alloy sheet from the 5000 series; optionally mounting a metal insert onto the outer face; deep drawing or flow forming said sheet into the shell shape; optionally applying a PTFE, or ceramic, or sol-gel coating partially or entirely over the inner face; and optionally applying an enamel, PTFE, ceramic, or sol-gel coating partially or entirely over the outer face.

Description

[0051] The invention will be better understood from the study of an exemplary embodiment, taken without any limitation, illustrated in the attached figures, in which:

[0052] FIG. 1 is a schematic representation in cross-section of an exemplary embodiment of a cooking utensil according to the prior art,

[0053] FIG. 2 is a schematic representation in cross-section of an exemplary embodiment of a cooking utensil according to the invention,

[0054] FIG. 3 is a partial schematic representation in cross-section of an alternative embodiment of a cooking utensil according to the prior art,

[0055] FIG. 4 is a representation of a metal insert inserted into the bottom of the cooking utensil illustrated in FIG. 3,

[0056] FIG. 5 is a partial schematic representation in cross-section of an alternative embodiment of a cooking utensil according to the invention,

[0057] FIG. 6 is a representation of a metal insert inserted into the bottom of the cooking utensil illustrated in FIG. 5.

[0058] FIGS. 1 and 2 illustrate cooking utensils 1′, 1 comprising a metal shell 2′, 2 having a bottom wall 21′, 21 and a side wall 31′, 31 rising up around the bottom wall 21′, 21. The shell 2′, 2 is a flow-formed aluminum alloy sheet. As an alternative, the shell 2′, 2 could be a deep-drawn aluminum alloy sheet. The bottom wall 21′, 21 has an inner face 211′, 211 intended for cooking food and an outer face 212′, 212 intended to be placed in proximity to a source of heat. If desired, the inner face 211′, 211 may be partially or entirely coated with a coating, for example a PTFE coating, or a ceramic coating, or a sol-gel coating. If desired, the outer face 212′, 212 may be partially or entirely coated with a coating, for example a PTFE coating, or a ceramic coating, or a sol-gel coating. If desired, the cooking utensil 1′, 1 may comprise a handle (not shown in FIGS. 1 and 2) mounted on the shell 2′, 2.

[0059] According to the alternative embodiments illustrated in FIGS. 3 and 5, the cooking utensil 1′, 1 comprises a handle 5′, 5 attached to the shell 2′ 2. Furthermore, a metal insert 4′, 4 is mounted directly onto the outer face 212′, 212 of the bottom wall 21′, 21. FIGS. 4 and 6 show the metal inserts 4′, 4 that are present in the cooking utensils 1′, 1 shown in FIGS. 3 and 5. The metal inserts 4′, 4 are formed by grids. The metal inserts 4′, 4 may be produced from a ferromagnetic material, particularly from ferritic stainless steel, in order to obtain a cooking utensil 1′, 1 compatible with induction heating. The thickness of the metal inserts is for example of the order of 0.6 mm.

[0060] In the cooking utensils of the prior art illustrated in FIGS. 1, 3 and 4, the shell 2′ is a 4006 aluminum alloy sheet from the 4000 series, with a diameter of 28 cm. The bottom wall 21′ has a thickness of the order of 4.5 mm. The side wall 31′ has a thickness of the order of 3 mm, said side wall thickness corresponding to a minimum thickness measured below the outer edge of the shell 2′. The ratio between the thickness of the bottom wall 21′ and the thickness of the side wall 31′ is of the order of 1.5.

[0061] In the cooking utensils according to the invention illustrated in FIGS. 2, 5 and 6, the shell 2 is a 6082 aluminum alloy sheet from the 6000 series, with a diameter of 28 cm. The height of the shell 2 is of the order of 55 mm, i.e., a height/diameter ratio of the order of 0.2. The bottom wall 21 has a thickness of the order of 6 mm. The side wall 31 has a thickness of the order of 2 mm, said side wall thickness corresponding to a minimum thickness measured below the outer edge of the shell 2. The ratio between the thickness of the bottom wall 21 and the thickness of the side wall 31 is of the order of 3. As an alternative, the shell could be a 5754 aluminum alloy sheet from the 5000 series, or a 5083 aluminum alloy sheet from the 5000 series. As an alternative, the shell could have other diameters, and/or other heights, and/or other thicknesses of the bottom wall 21, and/or other thicknesses of the side wall 31.

EXAMPLES

[0062] Tests were carried out with two 6082 alloy prototypes (PR21 and PR22) (skillet 28 cm in diameter, produced from 6082 alloy, corresponding to the alternative embodiment of FIG. 5, with a side wall thickness of 2 mm, a bottom wall thickness of 6 mm, a side wall height of 55 mm, a bottom diameter of 225 mm, and an openwork stainless steel grid with diameter of 225 mm, shown in FIG. 6).

[0063] The cooking utensil of reference used is the PO28GCBV Expertise skillet (skillet 28 cm in diameter, Grand Chef Edge pourer, produced from 4006 alloy, corresponding to the alternative embodiment of FIG. 3, with a side wall thickness of 3 mm, a bottom wall thickness of 4.5 mm, a side wall height of 55 mm, a bottom diameter of 210 mm, and an openwork stainless steel grid with diameter of 205 mm, shown in FIG. 4).

[0064] The two grids have an identical central part, the difference in diameter pertaining to a non-openwork outer ring.

[0065] Preheating Test

[0066] The preheating tests were carried out on an induction hob.

[0067] The preheating test consists of placing the empty skillet on the heating means. Once one of the points of the utensil reaches 180° C., the maximum temperature difference between two points of the bottom is measured in order to quantify the homogeneity criterion. The preheating time corresponds to the time necessary for a point to reach 180° C.

TABLE-US-00005 TABLE 5 Calculation of the T°max − min difference on the cooking surface when T max = 180° C. ΔT.sup.0 Gain Standard Prod N.sup.o1 EXPERTISE 93 35% Prototype 6082 PR22 60

[0068] It will be noted that the increase of the bottom wall/side wall ratio improves the homogeneity of the cooking utensil while reducing the weight thereof.

[0069] Egg White Test

[0070] Egg white tests were carried out on several induction hobs (characteristics described in the table below).

[0071] This cooking test consists of determining the time necessary for the spread of coagulation of 150 g of egg white over 100% of the cooking surface of the skillet. To do this, beaten egg whites are poured into a cold skillet. The heating means is started; then the percent of coagulation is observed after stopping cooking and rinsing the uncoagulated part of the egg whites under water. The operation is repeated, increasing the cooking time by 10 seconds, until complete coagulation of the egg whites.

[0072] The increase of the thickness ratio relative to the standard thus makes it possible to significantly reduce this cooking time while still reducing the weight of the cooking utensil.

TABLE-US-00006 TABLE 6 Reference Plate “BALAY” ® “WHIRLPOOL” ® “BOSCH” ® Ref:3EB915LR Ref: ACM 701 Ref: PIL611B1SE Power: 2200 W Power: 2000 W Power: 2200 W Ø Inductor 230 mm Ø Inductor 250 mm Ø Inductor 272 mm Time Gain Time Gain Time Gain EXPERTISE 84 67 52 PR21 39 54% 53 21% 37 29%

[0073] Other tests were carried out with two 5754 alloy prototypes and with two 5083 alloy prototypes (skillet 28 cm in diameter, corresponding to the alternative embodiment of FIG. 5, with a side wall thickness of 1.9 mm or 1 mm, a bottom wall thickness of 4.5 mm or 8 mm, a side wall height of 55 mm, a bottom diameter of 225 mm, and an openwork stainless steel grid with diameter of 205 mm, shown in FIG. 4).

[0074] The cooking utensil of reference used is also the PO28GCBV Expertise skillet (skillet 28 cm in diameter, Grand Chef Edge pourer, produced from 4006 alloy, corresponding to the alternative embodiment of FIG. 3, with a side wall thickness of 3 mm, a bottom wall thickness of 4.5 mm, a side wall height of 55 mm, a bottom diameter of 210 mm, and an openwork stainless steel grid with diameter of 205 mm, shown in FIG. 4).

[0075] Preheating Test

[0076] The preheating tests were carried out on an induction hob under the same conditions as the preceding test, except the average power was of the order of 2000 W instead of 2200 W.

TABLE-US-00007 TABLE 7 PREHEATING TEST Calculation of the T° max − min difference on the cooking surface when T max = 180° C. Thickness Bottom Thickness Skirt Time to reach T. avg. T. min T. max Δ T° Avg Pwr No. ALLOY (mm) (mm) 180° C. (s) [° C.] [° C.] [° C.] (° C.) (W) PO 2 5754 4.5 1.9 42 132 55 183 128 2021 PO 3 5754 8 1 75 148 96 180 84 2024 PO 5 5083 4.5 1.9 40 131 63 180 117 2002 PO 6 5083 8 1 70 148 102 181 79 2023 Standard 4006 4.5 3 58 140 91 181 90 2019

[0077] For a given alloy, it will be noted that the increase of the bottom wall/side wall ratio improves the heating homogeneity of the cooking utensil. It will also be noted that with the 5000 series alloys, a better heating homogeneity than that of the cooking utensil of reference can be obtained, by using a higher bottom wall/side wall ratio.