FR3096248A1 - CULINARY ARTICLE WITH A THINNED SIDE WALL - Google Patents

Abstract

The invention relates to a cookware (1) comprising a metallic cap (2) having a bottom wall (21) and a side wall (31) rising around the bottom wall (21), said bottom wall ( 21) having an internal face (211) intended for cooking food and an external face (212) intended to be placed near a heat source. According to the invention, said cap (2) is a stamped or flow-formed aluminum alloy sheet of the 6000 series or of the 5000 series and the bottom wall (21) has a thickness at least 2 times greater than that of the side wall (31), preferably at least 2.5 times greater than that of the side wall (31). The invention also relates to the method of manufacturing said cookware. Figure for the abstract: Fig. 2

Description

Description Title of the invention: CULINARY ARTICLE HAVING A THINNED SIDE WALL

[0001] The present invention relates to the technical field of cookware or cooking receptacles made from a stamped or aluminum alloy sheet.

[0002] Cooking vessels generally comprise a bottom intended to be placed on a cooking hearth (such as for example an electric hotplate, an induction hotplate, a fuel burner, or the like), this bottom being surrounded by a side wall rising around the bottom.

The upper face of the bottom forms a food cooking surface.

The underside of the bottom forms a heated surface.

The present invention relates in particular, but not exclusively, to pan-type cooking vessels.

Pan-type cooking vessels can be defined by a height less than their width or diameter.

Generally the width or the diameter of such cooking vessels is several times greater than their height.

[0004] The use of aluminum alloys in the culinary field has been known for years.

The good thermal conductivity dc makes it possible to envisage the production of cooking containers having an aluminum alloy body.

[0005] In cooking vessels having an aluminum alloy body, the side wall acts as a cooling fin, which helps to limit the heating of the peripheral part of the bottom.

This results in a temperature differential on the bottom, in particular between the center and the periphery of the heating surface.

[0006] The distribution of the material used for a cooking container can be described by the bottom thickness ratio! thickness dc the side wall.

In usual practice for aluminum alloy cooking containers this bottom thickness ratio! thickness of the side wall does not exceed 1.8, in particular for cooking containers made from a sheet of stamped or flow-formed aluminum alloy.

A pan dc 28 cm in diameter has a bottom thickness of 5.1 mm and a side wall thickness of 2.9 mm, a ratio of 1.76.

[0007] One of the main criteria for evaluating the quality of a cooking vessel is its cooking homogeneity.

Cooking uniformity corresponds to the ability of the cooking vessel to cook the food evenly, regardless of the location of the food on the bottom of the cooking vessel.

[0008] A disadvantage of aluminum alloy cooking vessels made from a stamped or flow-formed aluminum alloy sheet lies in the sensitivity 2 of the cooking surface to temperature variations caused by the side wall.

During preheating, significant temperature differences can be observed on the cooking surface, with for example a temperature of 180°C at the hottest part of the cooking surface and less than 120°C at the hottest part of the cooking surface. least hot on the cooking surface.

These temperature differences contribute to reducing the uniformity of cooking of the food cooked in the cooking vessel.

[0009] The objective is to manufacture cooking containers with a distribution of the material according to its thermal role, in order to improve both its homogeneity and preheating properties while limiting the increase in the weight of the article.

An object of the present invention is to provide a cooking vessel comprising an aluminum alloy cap made from a sheet of stamped aluminum alloy or fluotournéc, in which the homogeneity of the temperature of the cooking surface is improved, without causing an excessive increase in the mass of the cooking vessel.

[0011] This object is achieved with a cooking utensil comprising a metal cap having a bottom wall and a side wall rising around the bottom wall, said bottom wall having an internal face intended for cooking food and a outer face intended to be placed close to a heat source, in that said cap is a stamped or flow-turned aluminum alloy sheet of the 6000 series or the 5000 series and that the bottom wall has a thickness at least 2 times greater than that of the side wall, preferably at least 2.5 times greater than that of the side wall.

Preferably, the bottom wall has a thickness less than or equal to 15 times that of the side wall, preferably less than or equal to 13.5 times that of the side wall.

[0013] Preferably, the cap has a diameter/height ratio of less than 0.5, and preferably less than 0.3.

[0014] Preferably, the cap has a diameter/height ratio of between 0.5 and 0.1, and preferably of between 0.3 and 0.1.

[0015] The use of aluminum alloys in the culinary field has been known for years.

However, the usual alloy grades (Al 1050, Al 1200, Al 3003, Al 4006) have low mechanical strength properties.

[0016] The use of alloys from the 6000 series or the 5000 series makes it possible to rethink the design of cooking vessels to improve their cooking homogeneity while reducing their mass and limiting the increase in preheating time.

[0017] It is recalled that the alloys used must comply with food standards (Zn content<0.25% and Cu content<0.6%).

6000 series (aluminum magnesium silicon) 3

[0018] The alloying elements of this series are magnesium (Mg) and silicon (Si).

This alloy family is of great industrial importance.

It is widely used for profiles.

[0019] They have a very good aptitude for deformation (mainly spinning, forging) and for cold forming in the annealed state.

Their mechanical characteristics are average and are lower than those of alloys 2000 and 7000.

These characteristics can be increased by adding silicon which will give the hardening Mg2Si precipitate.

They have excellent resistance to corrosion, particularly atmospheric.

They weld very well (arc welding or brazing).

They can be divided into two groups:

[0021] - a group whose compositions are more loaded with magnesium and silicon (6061, 6082 for example).

They are used for structural applications (framework, pylon, etc.), as well as in aeronautics (electrical connections, on-board electronic altiers, etc.); - a second category less charged in silicon which consequently will have weaker mechanical characteristics.

This is the case of 6060 which will allow high spinning speeds but which will have weaker mechanical characteristics.

[0022] Tl will be used for example in decoration and furnishings, metal carpentry.

Tl should also note the existence of 6101 formerly called Almelec.

This alloy has been widely used for its electrical conductor abilities.

It was used in particular for the manufacture of medium and high voltage lines in France.

[0024] [Tables 1] Ccareosition Other Other Fe Cu Mn Mg Cr Ni Ti Zr*T each total Al le 0.10! 0.3.5 remainder 0.30 (1.10 0.60 0.05 0.15 0.10 0.05 0.15 le -C1.4 0.60 I. remainder 50 0.10 .00 1.20 0 .25 0.20 0.10 0.05 0.15 0.35 remainder 0.50 0.10 0.03 0, g0 0.30 0.10 0.05 0.15 Alloy 6050 0.03 M-',,x.0, 60 Min 0.70 Max 1.30 60.62 6101 Max 0.70 100251 The concentrations are in mass percentage.

100261 Preferably, the aluminum alloy is from the 6000 series of the 6082 grade.

This alloy has a high elastic limit, and is harder than the aluminum alloys usually used to make cooking vessels, which makes it possible to consider further reducing the thickness of the side wall of the cooking vessel, because of this better mechanical strength.

Series 5000 (aluminum magnesium) 100271 The alloying element is magnesium (up to 5%).

These are strain hardened alloys.

[0028] These alloys have average mechanical characteristics which increase with the magnesium content.

These characteristics will also increase with the strain hardening rate.

They have a good ability to deform, this ability decreasing if the magnesium content increases.

They have excellent welding behavior and as such are used in welding boilermaking.

They also behave well at low temperatures.

They have a good corrosion behavior which justifies their use in marine applications.

[0030] They are used in shipbuilding, transport and the chemical industry.

[0031] [Tableaux2] Composition Other Other:Mliage- - Si 1e Cu Mn Ma Cr Ni Ln Ti Zri-Ti each total 5005 Mit 7 0.501 le rege Ma;).-;..0.30. 0.70 0.20 020.1.10 0.101 0.25 0.05 0.15 5086 Min. 0.20.3.50.0.05 the rest Max_ 0.40 0.50 0;10,070 4.50 0.4.5 7,025. 0.157/ 0.05 0.15 100321 The concentrations are in percentage by mass.

100331 Advantageously, the aluminum alloy is L series 5000 of grade 5754.

This alloy is harder than the 6000 series aluminum alloy of the 6082 grade, which also makes it possible to consider further reducing the thickness of the side wall of the cooking vessel, due to this better mechanical strength. .

[0034] [Tableaux3] 5754 (AVVialMg3): Nominal chemical composition % (according to standard EN 573-i): H Other Si Fe Cu Mn Mg Cr Zn Remarks Al Chue Total 0.40 0.40 0.10 0.50 2 .6-3.6 0.30 0.20 0.10-0.6 MnCr 0.15 0.05 0.15 Remainder

[0035] Advantageously, 1 aluminum alloy is of L series 5000 of grade 5083.

This alloy is harder than the 5000 series aluminum alloy of the 5754 grade, which also makes it possible to consider further reducing the thickness of the side wall of the cooking vessel, due to this better mechanical strength. .

[0036] [Tableaux4] 5083 (AW-AIIVIg4151WIn0,7) Nominal chemical composition % (according to standard EN 573 1): Fe CiA Mn Mg Cr Ni Zr T Other Al Each Total 0.40 040 0.10 04-10 4.0- 4.9 10.05-0.25 - 0.25 0.15 0.05 0.15 Remainder

[0037] If desired, the internal face can be partially or entirely coated, in particular with a PTFE, ceramic or sol-gel coating.

If desired, the outer face can be partially or completely coated, in particular with an enamel, PTFE, ceramic or sol-gel coating.

If desired, a metal insert can be added under the bottom of the cooking container, on the side of the outer face, to allow the heating of the cooking container on an induction heating plate.

[0040] Preferably, the metal insert is formed by a grid.

This grid can be assembled by stamping, for example by cold stamping, preferably before shaping the alloy sheet.

Its thickness is between 0.3 and 1 mm, preferably about 0.6 mm.

The holes in the grid can have a diameter of between 2 and 4 mm, preferably about 3 mm.

[0042] Preferably, the metal insert is made of a ferromagnetic material.

The metal insert makes the cookware according to the invention compatible with induction heating.

Another object of the invention relates to a method of manufacturing a culinary item according to the invention comprising the following steps:

[0045] - Provide a sheet of aluminum alloy from the 6000 series or the 5000 series, Possibly add a metal insert to the external face, Stamp or fluotoumer said sheet in the shape of a cap, Possibly apply to the internal face partially or entirely a PTFE, or ceramic, or sol-gel coating, Optionally apply on the external face partially or entirely an enamel, PTFE, ceramic, or sol-gel coating.

Another object of the invention relates to the use of a metal cap in the form of a sheet of stamped or flow-formed aluminum alloy of the 6000 series or the 5000 series to improve the preheating time. of a culinary item.

The means used consists in increasing the thickness of the bottom wall and decreasing that of the side wall, which amounts to maximizing the bottom wall/side wall thickness ratio.

The difficulty here is to distribute the material ideally according to its thermal role while respecting the imperative of mechanical resistance (in particular at the point of attachment of a handle on the side wall).

[0048] The implementation of these constructions does not require specific transformation processes.

The parameters used during the stamping, flow forming or coining operations to assemble a base compatible with induction heating obviously have to be adapted to the new thicknesses to be obtained.

For example, the striking force for the insertion of a grid will for example be significantly increased to compensate for the greater resistance to grid penetration that the new alloy will provide.

The invention will be better understood on studying the exemplary embodiments, taken in no way limiting, illustrated in the appended figures, in which:

[0050] [fig.1] FIG. 1 is a diagrammatic sectional representation of an embodiment of a cookware according to the prior art,

[0051] [fig.2] FIG. 2 is a diagrammatic sectional representation of an embodiment of a cookware according to the invention,

[0052] [fig.3] Figure 3 is a partial schematic representation in section of an alternative embodiment of a culinary item according to the prior art,

[0053] [fig.4] Figure 4 is a representation of a metal insert inserted into the bottom of the cookware shown in Figure 3,

[0054] [fig.5] Figure 5 is a partial schematic sectional representation of an alternative embodiment of a culinary item according to the invention,

[0055] [fig.6] Figure 6 is a representation of a metal insert inserted into the bottom of the cookware shown in Figure 5.

Figures 1 and 2 illustrate cookware 1', 1 comprising a metal cap 2', 2 having a bottom wall 21', 21 and a side wall 31', 31 rising around the bottom wall 21', 21.

The cap 2', 2 is a fluotoumée aluminum alloy sheet.

As a variant, the cap 2', 2 could be a stamped aluminum alloy sheet.

The bottom wall 21', 21 has an internal face 211', 211 intended for cooking food and an external face 212', 212 intended to be placed close to a heat source.

If desired, the internal face 211', 211 can 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 can 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 culinary item 1', 1 may include a handle (not shown in Figures 1 and 2) mounted on the cap 2', 2.

According to the alternative embodiments illustrated in Figures 3 and 5, the culinary item 1', 71 comprises a handle 5', 5 fixed to the cap 2', 2.

Furthermore, a metal insert 4', 4 is attached to the outer face 212', 212 of the bottom wall 21', 21.

Figures 4 and 6 show the metal inserts 4', 4 present in the cookware 1', 1 illustrated in Figures 3 and 5.

The metal inserts 4', 4 are formed by grids.

The metal inserts 4', 4 can be made of ferromagnetic material, in particular ferritic stainless steel, to obtain a cookware 1', 1 compatible with induction heating.

The thickness of the metal inserts is for example dc of the order of 0.6 mm.

In the cookware of the prior art illustrated in Figures 1, 3 and 4, the cap 2' is an aluminum alloy sheet from the 4000 series of the grade 4006, 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, this side wall thickness corresponding to a minimum thickness measured below the outer edge of the cap 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.

In the cookware according to the invention illustrated in Figures 2, Set 6, the cap 2 is an aluminum alloy sheet of the 6000 series of the grade 6082, with a diameter of 28 cm.

The height of the cap 2 is of the order of 55 mm, ie a height ratio! diameter 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, this side wall thickness corresponding to a minimum thickness measured below the outer edge of the cap 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 a variant, the cap could be either a 5000 series aluminum alloy sheet of the 5754 grade, or a 5000 series aluminum alloy sheet of the 5083 grade.

Alternatively, the cap could have other diameters, and/or other heights, and/or other bottom wall thicknesses 21, and/or other side wall thicknesses 31.

EXAMPLES

[0060] Tests were carried out with two prototypes in 6082 alloy (PR21 and PR22) (stove with a diameter of 28 cm, made of 6082 alloy, corresponding to the embodiment variant in 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 a perforated stainless steel grid diameter of 225 mm, shown in Figure 6).

The reference culinary item used is the P028GCBV Expertise frying pan (a frying pan with a diameter of 28 cm Grand Chef Pouring edge, made of 4006 alloy, corresponding to the embodiment variant 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 a perforated stainless steel grid diameter of 205 mm shown in Figure 4).

The two grids have an identical central part, the difference in diameter corresponds to a non-perforated outer ring.

[0063] PREHEATING TEST

The preheating tests were carried out on an induction plate.

The preheating test consists of placing the pan empty on the heating medium.

Once one of the points of the article 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 required for a point to reach 180°C.

[0066] [Tableaux5] TEST NE HEATING Ca k ' rï s rfaue of cooking when r imam = 120 C Ar m Gain Standard PÎOEd t1 EXPERTISE 93 85% Pmtatype &082 PR22 50

It is noted that the increase in the bottom wall/side wall ratio improves the homogeneity of the cookware while reducing its weight.

[0068] WHITE EGG TEST

The egg white tests were carried out on several induction plates (characteristics described in the table below).

[0070] This cooking test consists in recording the time required for the coagulation of 150 g of egg white to spread over 100% of the cooking surface of the pan.

To do this, pour beaten egg whites into a cold pan.

The heating means are started and then the percentage of coagulation is observed after stopping the cooking and rinsing under water the non-coagulated part of the egg whites.

The operation is repeated, increasing the cooking time by 10 seconds, until the egg whites have completely coagulated.

The increase in the thickness ratio relative to the standard thus makes it possible to significantly reduce this cooking time while reducing the weight of the cookware.

[0072] 9 [Tableaux6] Fléfèrerece Plate 'SALM-G-WFilFtLPOCir e "BOSCI i'' V Ref.

3E89151 Ref: ACM7131 Ref: NLMJS1SE Power .

2200W Power .

2000W Power .

2200W 0 inductor 230 mm 0 inductor 250 min 0 inductor ZlZmm Time Gain Time Gain Time Gain.

EXPERTISE 34 51 52 PRIt 39 54% 21% 31 29%

[0073] Other tests were carried out with two prototypes in 5754 alloy and with two prototypes in 5083 alloy (stove with a diameter of 28 cm. corresponding to the embodiment variant in Figure 5. with a side wall thickness of 1. 9 mm or 1 min. 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 a perforated stainless steel grid diameter of 205 mm shown on Figure 4).

The reference cookware used is also the P028GCBV Expertise frying pan (Grand Chef Pouring Edge frying pan with a diameter of 28 cm, made of 4006 alloy, corresponding to the embodiment variant in FIG. 3, with a side wall thickness of 3 mm, a bottom wall thickness of 4.5 min, a side wall height of 55 mm, a bottom diameter of 210 mm and a perforated stainless steel grid diameter of 205 mm shown in Figure 4).

[0075] PREHEATING TEST

The preheating tests were carried out on an induction hob under the same conditions as the previous test, except for the average power of the order of 2000 W instead of 2200 W.

[0077] [Tablcaux7] PRE-HEATING TEST CaIcu of: the difference of ro rr3ax - min on the cooking surface when r. max 189°C N° ALUAGE Ep.

Ep.

Skirt (my) Time for T. crtoy. rC] T.. mini PC] T. maxç. rC1 to r P. avg, (N) Bottom reach I80°C (t) (mm) (s) P02 5754 45 1.9 42 132 55 183 128 2021 P03 5754 8 1 75 148 96 180 84 2024 P05 5083 1, 9 40 131 63 180 117 2092 P06 5083 a I 70 148 102 181 79 2023 Standard 4006 sa 140 91 181 90 2019

For a given alloy, it is noted that increasing the bottom wall/side wall ratio improves the uniformity of heating of the cookware.

It is also noted that with the 5000 series alloys a better heating homogeneity than that of the reference cookware can be obtained, by using a higher bottom wall/side wall ratio.

11 [Claim 1] [Claim 2] [Claim 3] [Claim 4] [Claim 5] [Claim 6] [Claim 7] [Claim 8] [Claim 9] [Claim 10] [Claim 11] [Claim 12]

Claims (1)

CLAIMS Cookware (1) comprising a metal cap (2) having a bottom wall (21) and a side wall (31) rising around the bottom wall (21), said bottom wall (21) having a internal face (211) intended for cooking food and an external face (212) intended to be placed close to a source of heat, characterized in that the said cap (2) is a sheet of stamped aluminum alloy or of the 6000 series or the 5000 series and in that the bottom wall (21) has a thickness at least 2 times greater than that of the side wall (31), preferably at least 2.5 times greater than that of the side wall (31). Culinary article according to Claim 1, characterized in that the bottom wall (21) has a thickness less than or equal to 15 times that of the side wall (31), preferably less than or equal to 13.5 times that of the side (31). Cookware according to Claim 1 or 2, characterized in that the aluminum alloy is of the 6000 series of grade 6082. Cookware according to Claim 1 or 2, characterized in that the aluminum alloy is of the 5000 series of the 5754 grade. Cookware according to Claim 1 or 2, characterized in that the aluminum alloy is of the 5000 series of the 5083 grade. Cookware according to one of Claims 1 to 5, characterized in that in that the inner face (211) is partially or entirely coated with a PTFE, or ceramic, or sol-gel coating. Culinary article according to one of Claims 1 to 6, characterized in that the external face (212) is partially or entirely coated with an enamel, or PTFE, or ceramic, or sol-gel coating. Culinary article according to one of Claims 1 to 7, characterized in that a metal insert (4) is attached to the external face (212). Culinary article according to Claim 8, characterized in that the insert. metal (4) is formed by a grid. Culinary article according to one of Claims 8 or 9, characterized in that the metal insert (4) is made of ferromagnetic material. Culinary article according to any one of Claims 8 to 10, characterized in that it is compatible with induction heating. Cookware according to any one of Claims 1 to 11, characterized in that the cap (2) has a diameter/height ratio 12 [Claim 13] [Claim 14] [Claim 15] of less than 0.5, and preferably less than 0.3. Culinary article according to any one of Claims 1 to 12, characterized in that the cap (2) has a diameter/height ratio of between 0.5 and 0.1, and preferably between 0.3 and 0.1 . Process for the manufacture of a culinary article according to any one of claims 1 to 13 comprising the following steps: - Providing a sheet of aluminum alloy of the 6000 series or the 5000 series, - Optionally adding on the external face (212) a metal insert (4), - Stamping or flow-turning said sheet in the form of a cap (2), - Optionally applying to the internal face (211) partially or entirely a PTFE, or ceramic, or sol-gel coating. - Optionally apply on the external face (212) partially or entirely an enamel, PTFE, ceramic or sol-gel coating. Use of a metal cap (2) in the form of a stamped or flow-formed aluminum alloy sheet of the 6000 series or of the 5000 series to improve the preheating time of a cooking utensil.