TECHNICAL FIELD

[0001] This disclosure relates generally to cookware vessels, and more specifically to a cookware vessel having an inner vessel positioned within and coupled to an outer vessel.

BACKGROUND

[0002] Typically, certain cookware vessels (such as a hotpot in Asian cuisines) may include separate compartments that can store different foodstuffs during heating (and/or cooking). These traditional cookware vessels, however, may be deficient.

SUMMARY

[0003] In a first example, a method for forming a cookware vessel comprises: providing an outer vessel and an inner vessel, wherein the inner vessel has a smaller outer diameter than an inner diameter of the outer vessel, wherein the bottom of one of the inner vessel and the outer vessel includes a hole; inserting the inner vessel into the outer vessel so that at least a portion of the bottom of the inner vessel is disposed over at least a portion of the bottom of the outer vessel; coupling one or more portions of the bottom of the inner vessel to one or more portions of the bottom of the outer vessel; and coupling a layer of conductive material in-between an exterior cap and an exterior surface of the bottom of the outer vessel, wherein the layer of conductive material is coupled to at least an annular portion of the exterior surface of the bottom of the outer vessel.

[0004] Another example is any such method, further comprising forming the hole through the bottom of the one of the inner vessel and the outer vessel.

[0005] Another example is any such method, wherein forming the hole through the bottom of the one of the inner vessel and the outer vessel comprises forming the hole through the bottom of the inner vessel. [0006] Another example is any such method, wherein forming the hole through the bottom of the one of the inner vessel and the outer vessel comprises forming the hole through the bottom of the outer vessel.

[0007] Another example is any such method, wherein coupling the one or more portions of the bottom of the inner vessel to the one or more portions of the bottom of the outer vessel comprises laser welding the one or more portions of the bottom of the inner vessel to the one or more portions of the bottom of the outer vessel.

[0008] Another example is any such method, wherein coupling the layer of the conductive material in-between the exterior cap and the exterior surface of the bottom of the outer vessel comprises impact bonding the layer of the conductive material in-between the exterior cap and the exterior surface of the bottom of the outer vessel, wherein the layer of the conductive material is fused to at least the annular portion of the exterior surface of the bottom of the outer vessel.

[0009] Another example is any such method, wherein the conductive material comprises conductive metal.

[0010] Another example is any such method, wherein the inner vessel is inserted into the outer vessel so that at least an annular portion of an external surface of the bottom of the inner vessel is disposed over at least a portion of an internal surface of the bottom of the outer vessel.

[0011] Another example is any such method, wherein the bottom of the outer vessel includes the hole, and wherein coupling the one or more portions of the bottom of the inner vessel to the one or more portions of the bottom of the outer vessel comprises laser welding one or more portions of an external surface of the bottom of the inner vessel to a perimeter of the hole in the bottom of the outer vessel.

[0012] In a second example, a cookware vessel comprises: an outer vessel having a bottom and a sidewall extending upward from the bottom of the outer vessel to a rim, the sidewall of the outer vessel surrounding the bottom of the outer vessel to form an outer liquid retaining compartment; an inner vessel coupled to the outer vessel in a location within the outer vessel, the inner vessel having a bottom and a sidewall extending upward from the bottom of the inner vessel to a rim, the sidewall of the inner vessel surrounding the bottom of the inner vessel to form an inner liquid retaining compartment, wherein the bottom of one of the inner vessel and the outer vessel includes a hole; a cap coupled to the outer vessel, the cap forming an exterior bottom of the cookware vessel; and a layer of a conductive material disposed in-between the cap and at least a portion of an external surface of the bottom of the outer vessel.

[0013] Another example is any such cookware vessel, wherein the bottom of the outer vessel includes the hole.

[0014] Another example is any such cookware vessel, wherein the layer of the conductive material is in direct thermal contact with at least a portion of the bottom of the inner vessel.

[0015] Another example is any such cookware vessel, wherein the bottom of the inner vessel includes a depression, wherein the depression of the bottom of the inner vessel is positioned in the hole in the bottom of the outer vessel.

[0016] Another example is any such cookware vessel, wherein the bottom of the inner vessel includes the hole.

[0017] Another example is any such cookware vessel, wherein the bottom of the outer vessel includes a depression, wherein the inner vessel is positioned in the depression of the bottom of the outer vessel.

[0018] Another example is any such cookware vessel, wherein: the outer vessel is made of metal; the inner vessel is made of metal; the cap is made of metal; and the conductive material comprises a metal that is more conductive than the metal of the cap, the metal of the inner vessel, and the metal of the outer vessel.

[0019] Another example is any such cookware vessel, wherein the rim of the inner vessel extends vertically above the rim of the outer vessel.

[0020] Another example is any such cookware vessel, wherein the cap extends outward at least beyond a diameter of the bottom of the inner vessel toward the sidewall of the outer vessel.

[0021] Another example is any such cookware vessel, wherein the layer of the conductive material is in direct thermal contact with at least a portion of the bottom of the outer vessel.

[0022] Another example is any such cookware vessel, further comprising a lid.

[0023] In a third example, an article of cookware comprises an outer cookware vessel having a substantially horizontal interior bottom portion and an exterior bottom portion opposing the interior bottom portion, a substantially upright sidewall extending upward from the interior bottom portion that terminates at an outer rim, the sidewall encircling said bottom to form a liquid retaining region; an inner vessel having a substantially horizontal bottom portion with at least an annular interior surface and an exterior surface opposing the interior surface, a substantially upright sidewall extending upward from the perimeter of annular interior surface to terminate at an inner rim, the upright sidewall encircling said bottom portion to form an interior region that is surrounded by the liquid retaining region of the outer cookware vessel; at least one layer of a conductive metal coupled in direct thermal communication with a least a central portion of the horizontal bottom portion of the inner vessel that is disposed with the annular interior surface; wherein the at least one layer of a conductive metal extends beyond the inner vessel to be coupled in direct thermal communication with the exterior bottom portion of the outer cookware vessel.

[0024] Another example is any such article of cookware, wherein the central portion of the horizontal bottom portion of the inner vessel is provided by the interior bottom portion of the outer cookware vessel.

[0025] Another example is any such article of cookware, wherein an annular interior surface of the inner cookware vessel is formed by an annular portion of the inner cookware vessel bottom coupled to an annular portion of the outer cookware vessel bottom.

[0026] Another example is any such article of cookware, wherein the annular portion of the inner cookware vessel bottom is coupled to an annular portion of the outer cookware vessel bottom by a perimeter welded at one of an inner circumference and outer circumference of the annular portions.

[0027] Another example is any such article of cookware, wherein the annular portion of the inner cookware vessel bottom is coupled to an annular portion of the outer cookware vessel bottom by a perimeter welded at both an inner circumference and outer circumference of the annular portions.

[0028] Another example is any such article of cookware, further comprising a cap forming the exterior bottom of the cookware article that extends at least beyond the at least one layer of a conductive metal.

[0029] In a fourth example, a hot pot includes a concentric inner vessel that is centered in an outer vessel, and further includes a stainless steel cap on the exterior bottom. A more conductive metal, such as aluminum, fills the space between the exterior bottom of the outer vessel and the exterior bottom of the inner vessel. The conductive metal is in direct thermal communication with the exterior bottom of the inner vessel. The outer vessel and inner vessel may be joined by laser welding about an inner and outer circumference. The inner and outer vessel have an overlapping bottom portion between the inner and outer circumference. The more conductive metal is attached to both vessels, such as by impact bonding a lower cap to the inner and outer vessel. The overlapping edges of the inner and outer vessel bottoms are preferably laser welded prior to impact bonding. BRIEF DESCRIPTION OF THE FIGURES

[0030] For a more complete understanding of the present disclosure and one or more examples of the features and advantages of the present disclosure, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

[0031] FIG. 1A is a combined exterior elevation and cross-sectional elevation view of a symmetrical half of one example of a cookware vessel.

[0032] FIG. IB is a cross-sectional plan view at section line B-B in FIG. 1A, at half the scale of FIG. 1A.

[0033] FIG. 2A is a schematic cross-section elevation view of another example of a cookware vessel.

[0034] FIGS. 2B-2D are schematic cross-section elevation views of the cookware vessel of

FIG. 2A at various points during fabrication.

[0035] FIG. 3A is a schematic cross-section elevation view of another example of a cookware vessel.

[0036] FIGS. 3B-3D are schematic cross-section elevation views of the cookware vessel of FIG. 3A at various points during fabrication.

[0037] FIG. 4 is a schematic cross-section elevation view of another example of a cookware vessel during fabrication.

[0038] FIG. 5 is a flow chart that illustrates one example method for fabricating a cookware vessel. DETAILED DESCRIPTION

[0039] Embodiments of the present disclosure are best understood by referring to FIGS. 1A-5 of the drawings, like numerals being used for like and corresponding parts of the various drawings.

[0040] Typically, certain cookware vessels (such as a hotpot in Asian cuisines) may include separate compartments that can store different foodstuffs during heating (and/or cooking). These traditional cookware vessels, however, may be deficient. For example, such typical vessels are commonly formed by simply attaching a smaller inner vessel within a larger outer vessel. This, however, can result in the inner vessel having a larger interior bottom thickness than the outer vessel, as the inner vessel bottom thickness is the combination of both the inner vessel bottom and the outer vessel bottom. This thicker bottom thickness may impede the transfer of heat from a heating element to the inner vessel. Additionally, because the inner vessel has a smaller diameter than the entire vessel, the inner vessel may not align well with the heating element. This can make it difficult to predict and control the heating rate of both compartments. The contents of one compartment may be too cool for serving, or the other compartment may be too hot or overcooked.

[0041] In contrast, the cookware vessels 1000 of FIGS . 1 A-4 may address one or more of these deficiencies. For example, the cookware vessels 1000 of FIGS. 1A-4 may include a hole in a portion of the bottom of the inner vessel or the outer vessel. This hole may prevent heat (from a heat source) from having to travel through both the inner vessel bottom and the outer vessel bottom to reach the foodstuffs contained within the inner vessel. As such, the cookware vessel 1000 may, in some examples, provide superior thermal uniformity in heating of a multi-compartment vessel, especially on induction burners. That is, the cookware vessel 1000 may, in some examples, provide a multi-compartment cookware vessel in which both compartments may heat their respective contents at comparable rates, with minimum variation from the nature and size of the heat source, and the ability to center the inner compartment to the heat source center.

[0042] The cookware vessel 1000 of FIGS. 1A-4 may, in some examples, further provide a multi-compartment vessel with suitable strength and adhesion of the bonds between the inner and outer compartment portion of the vessel. This may, in some examples, allow the cookware vessel 1000 to perform as well as a conventional single compartment vessel, and not suffer from a loss of durability or adhesion of the vessel that forms the inner compartment from thermal shock, accidental overheating, and/or thermal stress cycling fatigue from use.

[0043] The cookware vessel 1000 of FIGS. 1A-4 may, in some examples, further provide a multi-compartment vessel that is easier to clean. For example, the cookware vessel 1000 may be no more difficult to clean and maintain than a conventional single compartment vessel.

[0044] FIGS. 1A-1B illustrate one example of a cookware vessel 1000. As is illustrated in FIGS. 1A-1B, the cookware vessel 1000 includes an outer vessel 100, and further includes an inner vessel 200 disposed within the outer vessel 100. The inner vessel 200 may be disposed within the outer vessel 100 in any arrangement (e.g., a concentric arrangement, a non-concentric arrangement).

[0045] The cookware vessel 1000 may allow a user to heat (or cook) liquids, solids, and/or liquid-solid mixtures in separate compartments within the single cookware vessel 1000, in some examples. Furthermore, the cookware vessel 1000 may allow a user to heat (or cook) liquids, solids, and/or liquid-solid mixtures in separate compartments, where cookware vessel 1000 includes an inner compartment surrounded by an outer compartment, and where both compartments are isolated from each other to contain different foodstuffs. In some examples, the cookware vessel 1000 may take the form of any cooking and/or storage vessel that utilizes both an outer vessel and an inner vessel. As one example, the cookware vessel 1000 may take the form of a hot pot used in Asian cuisine, with an inner vessel 200 concentrically disposed within a surrounding outer vessel 100.

[0046] The outer vessel 100 of the cookware vessel 1000 includes a bottom 120 connected to a sidewall 110. The bottom 120 may have any shape. For example, an external surface 120a of the bottom 120, an internal surface 120b of the bottom 120, or the entire bottom 120 (when viewed from the top) may be shaped as a circle, an oval, a square, a rectangle, a diamond, an irregular shape, any other shape, or any combination of the preceding. As is illustrated, the entire bottom 120 is shaped as a circle (e.g., it has circular symmetry). The bottom 120 may further have any size. For example, the bottom 120 may have any length (or diameter), and any thickness. The bottom 120 may be substantially horizontal. For example, the bottom 120 may be horizontal, with an upward curve in the outer annular portion of the bottom 120. [0047] The sidewall 110 is connected to and surrounds the bottom 120. The sidewall 110 extends upward from the bottom 120 so as to form an outer compartment 101 for retaining foods and/or liquids. The sidewall 110 may extend upward from the bottom 120 at any upward extending angle. For example, the sidewall 110 may extend upward at or substantially at (e.g., +/- 5 degrees) 90 degrees, 85 degrees, 80 degrees, 70 degrees, 60 degrees, 45 degrees, 95 degrees, 100 degrees,

110 degrees, 120 degrees, 135 degrees, any other upward extending angle, or any angle (or range of angles) in-between 45 degrees and 135 degrees. As another example, the sidewall 110 may be curved, such as by having a degree of curvature of or substantially of (e.g., +/- 5 degrees) 60 degrees, 55 degrees, 50 degree, 45 degrees, 40 degrees, 35 degrees, 30 degrees, any other degree of curvature, or any degree of curvature (or range of degrees of curvature) in-between 30 degrees and 60 degrees. The sidewall 110 may have any thickness.

[0048] The sidewall 110 may extend upward until it terminates at a rim 130 that defines an opening in the outer vessel 100. This opening may allow food and/or liquids to be inserted into and/or removed from the outer vessel 100. The rim 130, opening, or the entire outer vessel 100 (when viewed from the top) may be shaped as a circle, an oval, a square, a rectangle, a diamond, an irregular shape, any other shape, or any combination of the preceding. As is illustrated, outer vessel 100 is shaped as a circle (e.g., it has circular symmetry). The opening of the outer vessel 100 may have any size. For example, the opening may have any length (or diameter) in-between two opposing portions of the sidewall 110.

[0049] The rim 130 of the outer vessel 100 may be positioned at any vertical distance from the bottom 120. For example, the rim 130 may be positioned at a vertical distance of or substantially of (e.g., +/- 10%) 0.5 inches from the bottom 120, 1 inch from the bottom 120, 2 inches from the bottom 120, 3 inches from the bottom 120, 5 inches from the bottom 120, 6 inches from the bottom 120, 8 inches from the bottom 120, 10 inches from the bottom 120, 12 inches from the bottom 120, 24 inches from the bottom 120, any other vertical distance from the bottom 120, or any vertical distance (or range of vertical distances) in-between 0.5 inches and 24 inches.

[0050] The outer vessel 100 may be made of any material(s) that may allow a food item to be held, stored, and/or cooked (e.g., heating on a heat plate or induction burner, etc.) in the outer vessel 100. For example, the outer vessel 100 may be made of metal, glass, ceramic glass (e.g., opaque ceramic glass), pottery materials, any other material that may allow a food item to be held, stored, and/or cooked in the outer vessel 100, or any combination of the preceding. As is illustrated, the outer vessel 100 is made of metal. In a preferable example, the outer vessel 100 is made of stainless steel. In some examples, the outer vessel 100 may have a thickness of or substantially of (e.g., +/- 0.25 mm) 0.5 mm - 3 mm. This may, in some examples, allow for durability and reliability when the inner vessel 200 is coupled to the outer vessel 100, such as via laser welding.

[0051] The inner vessel 200 of the cookware vessel 1000 includes a bottom 220 connected to a sidewall 210. The bottom 220 may have any shape. For example, an external surface 220a of the bottom 220, an internal surface 220b of the bottom 220, or the entire bottom 220 (when viewed from the top) may be shaped as a circle, an oval, a square, a rectangle, a diamond, an irregular shape, any other shape, or any combination of the preceding. As is illustrated, the entire bottom 220 is shaped as a circle (e.g., it has circular symmetry). The bottom 220 may further have any size. For example, the bottom 220 may have any length (or diameter) that is less than that of bottom 120, and the bottom 220 may have any thickness. The bottom 220 may be substantially horizontal. For example, the bottom 220 may be horizontal, with an upward curve in the outer annular portion of the bottom 220.

[0052] The sidewall 210 is connected to and surrounds the bottom 220. The sidewall 210 extends upward from the bottom 220 so as to form an inner compartment 201 for retaining foods and/or liquids. The sidewall 210 may extend upward from the bottom 220 at any upward extending angle. For example, the sidewall 210 may extend upward at or substantially at (e.g., +/- 5 degrees) 90 degrees, 85 degrees, 80 degrees, 70 degrees, 60 degrees, 45 degrees, 95 degrees, 100 degrees, 110 degrees, 120 degrees, 135 degrees, any other upward extending angle, or any angle (or range of angles) in-between 45 degrees and 135 degrees. As another example, the sidewall 210 may be curved, such as by having a degree of curvature of or substantially of (e.g., +/- 5 degrees) 60 degrees, 55 degrees, 50 degree, 45 degrees, 40 degrees, 35 degrees, 30 degrees, any other degree of curvature, or any degree of curvature (or range of degrees of curvature) in-between 30 degrees and 60 degrees. The sidewall 210 may have any thickness. [0053] The sidewall 210 may extend upward until it terminates at a rim 230 that defines an opening in the inner vessel 200. This opening may allow food and/or liquids to be inserted into and/or removed from the inner vessel 200. The rim 230, opening, or the entire inner vessel 200 (when viewed from the top) may be shaped as a circle, an oval, a square, a rectangle, a diamond, an irregular shape, any other shape, or any combination of the preceding. As is illustrated, inner vessel 200 is shaped as a circle (e.g., it has circular symmetry). The opening of the inner vessel 200 may have any size. For example, the opening may have any length (or diameter) in-between two opposing portions of the sidewall 210, where the length (or diameter) of the opening of the inner vessel 200 is less than the length (or diameter) of the opening of the outer vessel 100.

[0054] The rim 230 of the inner vessel 200 may be positioned at any vertical distance from the bottom 220. For example, the rim 230 may be positioned at a vertical distance of or substantially of (e.g., +/- 10%) 0.5 inches from the bottom 220, 1 inch from the bottom 220, 2 inches from the bottom 220, 3 inches from the bottom 220, 5 inches from the bottom 220, 6 inches from the bottom 220, 8 inches from the bottom 220, 10 inches from the bottom 220, 12 inches from the bottom 220, 24 inches from the bottom 220, any other vertical distance from the bottom 220, or any vertical distance (or range of vertical distances) in-between 0.5 inches and 24 inches.

[0055] As is illustrated, the rim 230 of the inner vessel 200 is positioned at a location that is vertically above the location of the rim 130 of the outer vessel 100. That is, the rim 230 of the inner vessel 200 may extend vertically above the rim 130 of the outer vessel 100. This may facilitate the pouring of liquids (e.g., water, broth, oil) into the outer compartment 101, in some examples. In other examples, the rim 230 of the inner vessel 200 may be positioned at a location that is vertically below the location of the rim 130 of the outer vessel 100, or both rims 130/230 may be positioned at the same height.

[0056] The inner vessel 200 may be made of any material(s) that may allow a food item to be held, stored, and/or cooked (e.g., heating on a heat plate or induction burner, etc.) in the inner vessel 200. For example, the inner vessel 200 may be made of metal, glass, ceramic glass (e.g., opaque ceramic glass), pottery materials, any other material that may allow a food item to be held, stored, and/or cooked in the inner vessel 200, or any combination of the preceding. As is illustrated, the inner vessel 200 is made of metal. In a preferable example, the inner vessel 200 is made of stainless steel. In some examples, the inner vessel 200 may have a thickness of or substantially of (e.g., +/- 0.25 mm) 0.5 mm - 3 mm. This may, in some examples, allow for durability and reliability when the inner vessel 200 is coupled to the outer vessel 100, such as via laser welding.

[0057] The inner vessel 200 is positioned within (and coupled to) the outer vessel 100. For example, as is illustrated in FIGS. 1A-1B, at least a portion of the exterior surface 220a of the bottom 220 of the inner vessel 200 may be coupled to the interior surface 120b of the bottom 120 of the outer vessel 100. Examples of the coupling of the inner vessel 200 to the outer vessel 100 are discussed below. In order to be positioned within (and coupled to) the outer vessel 100, the inner vessel 200 may have an outer diameter that is smaller than an inner diameter of the outer vessel 100.

[0058] The cookware vessel 1000 may further include a cap 300 that forms an exterior bottom of the cookware vessel 1000. The cap 300 may be coupled to the outer vessel 100 (e.g., coupled to an exterior surface 120a of the outer vessel 100), and the cap 300 may extend over all or a portion of the exterior surface 120a of the outer vessel 100. As is seen in FIG. 1A, the cap 300 may have a size that causes it to extend outward at least beyond a diameter of the bottom 220 of the inner vessel 200 toward the sidewall 110 of the outer vessel 100.

[0059] The cookware vessel 1000 may also preferably include at least one layer of conductive material 310 that is coupled (e.g., bonded) to at least an exterior surface 120a of the outer vessel 100. This at least one layer of conductive material 310 may be coupled to at least an annular portion of the exterior surface 120a of the outer vessel 100, in some examples. The at least one layer of conductive material 310 may be coupled in-between the cap 300 and the exterior surface 120a of the bottom 120 of the outer vessel 100. In some examples, the cookware vessel 1000 may not include the cap 300. Instead, the conductive material 310 may be bonded to at least the exterior surface 120a of the outer vessel 100, without the cap 300. Examples of the bonding (or coupling) of the conductive material 310 (e.g., via brazing, press bonding, welding, and the like) to at least the exterior surface 120a of the outer vessel 100 are discussed below.

[0060] The cap 300 may be made of any suitable material. For example, the cap 300 may preferably be made of a ferromagnetic metal, such as ferromagnetic stainless steel, so as to be suitable for induction cooking. In other examples, the cap 300 may include a ferromagnetic outer layer, so as to be suitable for induction cooking. In some examples, the cap 300 may be made of a material that has a higher modulus and yield strength, so at least a portion of the conductive material 310 yields and thins as the conductive material 310 flows laterally under impact bonding to form a strong friction and/or metallic bond to the material on the exterior surface 120a of the outer vessel 100 and/or the exterior surface 220a of the inner vessel 200.

[0061] The conductive material 310 may be made of any suitable conductive material. For example, the conductive material 310 may be made of pure aluminum, alloyed aluminum, copper, copper alloys, copper clad aluminum, multiple layers of aluminum with perforation copper sheets or mesh disposed between at least one of the layers, any other suitable conductive material(s), or any combination of the preceding. The conductive material 310 may preferably be a material (e.g., metal) that is more conductive than the material (e.g., metal) that forms the cap 300, and also is more conductive than the material (e.g., metal) that forms one (or both) of the inner vessel 200 and outer vessel 100. In examples where the cookware vessel 1000 does not include a cap 300, the conductive material 310 may include a perforated mesh of ferromagnetic metal (e.g., ferromagnetic stainless steel) within it, or the conductive material 310 may include a ferromagnetic outer layer. The conductive layer 310 may have any thickness. In a preferable example, the conductive material 310 has a thickness of or substantially of (e.g., +/- 0.25 mm) 2 mm - 12 mm. The thickness of the conductive material 310, however, may vary depending on the conductivity, and the height of the flanges 125 and 225 (discussed below).

[0062] The cookware vessel 1000 may further include a lid for covering the inner vessel 200 and the outer vessel 100. An example of such a lid is illustrated as lid 150 in FIG. 3A.

[0063] FIG. 2A illustrates another example of a cookware vessel 1000. In particular, FIG. 2A illustrates further details regarding the coupling of outer vessel 100, inner vessel 200, cap 300, and conductive material 310, so as to form the cookware vessel 1000. FIGS. 2B-2D illustrate the fabrication of the example cookware vessel 1000 of FIG. 2A at various points during the fabrication.

[0064] The cookware vessel 1000 of FIGS. 2A-2D includes the outer vessel 100, inner vessel 200, cap 300, and conductive material 310. The outer vessel 100, inner vessel 200, cap 300, and conductive material 310 of FIGS . 2A-2D may be substantially similar to the outer vessel 100, inner vessel 200, cap 300, and conductive material 310 of FIG. 1A, discussed above.

[0065] As is illustrated in FIG. 2A, the bottom 120 of the outer vessel 100 may include a hole 121 formed or provided in the bottom 120. The hole 121 may extend between the interior surface 120b and the exterior surface 120a of the bottom 120, thereby extending all the way through the bottom 120. The hole 21 may be defined by a perimeter 122. The perimeter 122 of the hole 121 (and the hole 121, itself) may have any size and/or shape. The portion of the bottom 120 that surrounds the perimeter 122 may be referred to as the annular portion 120D of the bottom 120 of the outer vessel 100.

[0066] As a result of the hole 121 in the bottom 120 of the outer vessel 100, the inner vessel

200 (and its inner compartment 201) may have a central bottom portion 220C that is in direct contact with the conductive material 310 in a central portion 320 thereof. As such, when the exterior bottom of the cap 300 is heated (via a heat source, such as a heat plate), the heat will spread laterally through the conductive material 310, and the direct contact between the conductive material 310 and the central bottom portion 220C may cause the inner vessel 200 and the outer vessel 100 to generally heat up with the same speed. Thus, the food and/or liquid in the inner vessel 200 may generally heat up with the same speed as the food and/or liquid in the outer vessel 100.

[0067] The central bottom portion 220C of the inner vessel 200 is surrounded by an annular portion 220D. As a result of the hole 121, the annular portion 220D is the portion of the bottom 220 that is disposed on and coupled to the bottom 120 of the outer vessel 100. For example, as is illustrated, the annular portion 220D of the inner vessel 200 is disposed on and coupled to the annular portion 120D of bottom 120 of the outer vessel 100. The annular portion 120D and/or the annular portion 220D may have any width.

[0068] The coupling of the inner vessel 200 to the outer vessel 100 may be preferably by laser welding (as is described further below), but can alternatively be by spot welding, brazing, riveting, and the like. FIG. 2D illustrates how laser welds may be formed in continuous circles at the portion of the bottom 120 of the outer vessel 100 that is adjacent to a portion of the sidewall 210 of the inner vessel 100. [0069] The laser weld may preferably be formed as a continuous circle about the portion of the bottom 220 and bottom 120 adjacent the perimeter 122 of the hole 121. With the hole 121 provided in the outer vessel 100 (as is seen in FIGS. 2A-2D), the direction of the laser beam (arrow L2 in FIG. 2C) to form the inner circular weld W2 (in FIG. 2D) is from below the bottom 120 of the outer vessel 100. The inner vessel 200 may be rotated about a central cylindrical axis relative to the position of the laser beam that points at the interface to be welded. When the inner vessel 200 is not circular, the lasers or the vessels 100 and 200 can be moved on a numerically controlled table covering the perimeter of the interface to be bonded by welding. The overlap and presence of the perimeter welds W 1 and W2 (shown in FIG. 2D) may aid in providing a stable and robust connection of the outer and inner vessels 100 and 200. It may also avoid the total overlap of layers of each vessel 100/200 at the bottom, which can typically preclude reliable uniform and rapid heating in different conditions of use.

[0070] The direction of the laser beam (arrow LI in FIG. 2C) to form the outer circular weld W1 may be from above the bottom 120 of the outer vessel 100. This may, in some examples, be desirable to minimize any gap between the vessels 100/200 at the flange 125. As the inner vessel

200 may be locally heated about the sidewall 210 perimeter when forming a continuous weld W 1 (such as by rotating the outer vessel 100 or inner vessel 200 about a central cylindrical axis relative to the laser beam), absent constraining a local thermal expansion at the sidewall 210 perimeter, there may be significant residual stress in the weld W1 from contraction on cooling, in some examples. The weld may also be subject to thermal stress fatigue over repeated use. A partial rupture of the weld W 1 could make it more difficult to clean the vessel thoroughly, and facilitate propagation of the rupture along the weld line(s).

[0071] In some examples, constraining thermal expansion of the inner vessel 200 at the perimeter 122 when forming a continuous weld W2, may also form a more robust and reliable weld. The potential for thermal expansion of the inner vessel 200 at the perimeter 122 may first be reduced by minimizing any gap between the vessels 100 and 200 at the flange 125. The potential may be minimized further when the inner vessel 200 has depression 224 with a vertical flange 225 (as is discussed further below with regard to FIG. 4), and a gap between the vertical flange 224 and the perimeter 122 of the hole 121 is minimized. [0072] As is further illustrated, the bottom 120 of the outer vessel 100 may also include a depression 124 in the bottom 120. This depression 124 may allow the bottom 220 of the inner vessel 200 to be received within the outer depression 124, thereby assisting in coupling the inner vessel 200 to the outer vessel 100. For example, the depression 124 may allow for the stable centering and nesting of the inner vessel 200 within the outer vessel 100 for the steps of laser welding or any other method of attaching the bottoms 120/220 of the inner vessel 200 and outer vessel 100 together. The depression 124 may have a diameter at least as large as the outer diameter of the bottom 220 of the inner vessel 200. The depression 124 may be surrounded by a vertical flange 125 in the bottom 120. This vertical flange 125 may allow the inner vessel 200 to be lowered into the depression 124, causing the inner vessel 200 to sit within the depression 124, in some examples. The vertical flange 125 may have any height (H). In some examples, the height (H) of the flange 125 may, preferably, be or substantially be (e.g., +/- 0.25 mm) 0.5 mm - 5 mm, and may, more preferably, be or substantially be 1 mm - 3 mm.

[0073] FIG. 3A illustrates a further example of a cookware vessel 1000. In particular, FIG. 3A illustrates further details regarding the coupling of outer vessel 100, inner vessel 200, cap 300, and conductive material 310, so as to form the cookware vessel 1000. FIGS. 3B-3D illustrate the fabrication of the example cookware vessel 1000 of FIG. 3A at various points during the fabrication.

[0074] The cookware vessel 1000 of FIGS. 3A-3D may be substantially similar to the cookware vessel 1000 of FIGS. 2A-2D. As such, the cookware vessel 1000 of FIGS. 3A-3D may have an outer vessel 100, inner vessel 200, cap 300, and conductive material 310 that may be substantially similar to the outer vessel 100, inner vessel 200, cap 300, and conductive material 310 of FIG. 1A, discussed above.

[0075] However, unlike the cookware vessel 1000 of FIGS. 2A-2D, the cookware vessel 1000 of FIGS. 3A-3D may include a hole 221 formed or provided in the bottom 220 of the inner vessel

200 (as opposed to a hole in the outer vessel 100, as is seen in FIGS. 2A-2D). The hole 221 may extend between the interior surface 220b and the exterior surface 220a of the bottom 220, thereby extending all the way through the bottom 220. The hole 221 may be defined by a perimeter 222. The perimeter 222 of the hole 221 (and the hole 221, itself) may have any size and/or shape. [0076] As a result of the hole 221 in the bottom 220 of the inner vessel 200, the inner vessel 200 (and its inner compartment 201), itself, may not include a layer of material in the central bottom portion 220C of the bottom 220. As such, in the area of the central bottom portion 220C of the bottom 220, only a single layer of material (i.e., the bottom 120 of the outer vessel 100) will separate the conductive material 310 from the food and/or liquid contained in the inner compartment 201. Essentially, the bottom 120 of the outer vessel 100 may operate as the bottom of the inner vessel 200 in the area of the central bottom portion 220C. Because of this single layer, the food and/or liquid in the inner compartment 201 of the inner vessel 200 may generally heat up with the same speed as the food and/or liquid in the outer compartment 101 of the outer vessel 100.

[0077] The portion of the bottom 220 of the outer vessel 200 that surrounds the perimeter 222 of the hole 221 may be referred to as the annular portion 220D of the bottom 220 of the outer vessel 200. This annular portion 220D is the portion of the bottom 220 that is disposed on and coupled to the bottom 120 of the outer vessel 100. The annular portion 220D may have any width.

[0078] The coupling of the inner vessel 200 to the outer vessel 100 may be preferably by laser welding (as is described further below), but can alternatively be by spot welding, brazing, riveting, and the like. FIG. 3D illustrates how laser welds may be formed in continuous circles at the portion of the bottom 120 of the outer vessel 100 that is adjacent to a portion of the sidewall 210 of the inner vessel 200.

[0079] The laser weld may preferably be formed as a continuous circle about the portion of the bottom 220 and bottom 120 adjacent the perimeter 222 of the hole 221. With the hole 221 provided in the inner vessel 200 (as is seen in FIGS. 3A-3D), the direction of the laser beam (arrow F2 in FIG. 3C) to form the inner circular weld W2 (shown in FIG. 3D) is from above the bottom 120 of the outer vessel 100. This may, in some examples, be desirable to minimize any gap between the vessels 100/200 at the flange 125. As the inner vessel 200 may be locally heated about the sidewall 210 perimeter when forming a continuous weld W1 (such as by rotating the outer vessel 100 or inner vessel 200 about a central cylindrical axis relative to the laser beam), absent constraining a local thermal expansion at the sidewall 210 perimeter, there may be significant residual stress in the weld W 1 from contraction on cooling. The weld may also be subject to thermal stress fatigue over repeated use. A partial rupture of the weld W1 could make it more difficult to clean the vessel thoroughly, and facilitate propagation of the rupture along the weld line(s).

[0080] In some examples, constraining thermal expansion of the inner vessel 200 at the perimeter 222 when forming a continuous weld W2, may also form a more robust and reliable weld. The potential for thermal expansion of the inner vessel 200 at the perimeter 222 or 122 may first be reduced by minimizing any gap between the vessels 100 and 200 at the flange 125. The potential may be minimized further when the inner vessel 200 has depression 224 with vertical flange 225 (as is discussed further below with regard to FIG. 4).

[0081] As is further illustrated, the bottom 120 of the outer vessel 100 may also include a depression 124 in the bottom 120. This depression 124 may allow the bottom 220 of the inner vessel 200 to be received within the outer depression 124, thereby assisting in coupling the inner vessel 200 to the outer vessel 100. For example, the depression 124 may allow for the stable centering and nesting of the inner vessel 200 within the outer vessel 100 for the steps of laser welding or any other method of attaching the bottoms 120/200 of the inner vessel 200 and outer vessel 100 together. The depression 124 may have a diameter at least as large as the outer diameter of the bottom 220 of the inner vessel 200. The depression 124 may be surrounded by a vertical flange 125 in the bottom 120. This vertical flange 125 may allow the inner vessel 200 to be lowered into the depression 124, causing the inner vessel 200 to sit within the depression 124, in some examples. The vertical flange 125 may have any height (H). In some examples, the height

(H) of the flange 125 may, preferably, be or substantially be (e.g., +/- 0.25 mm) 0.5 mm - 5 mm, and may, more preferably, be or substantially be 1 mm - 3 mm.

[0082] The cookware vessel 1000 may further include a lid 150 for covering the inner vessel 200 and the outer vessel 100. The lid 150 may have an expanse of a covering material that terminates at a lower rim 153. The lower rim 153 may be coupled to the rim 130 of the outer vessel 100, thereby sealing the cookware vessel 1000.

[0083] Modifications, additions, and/or substitutions may be made to the cookware vessel 1000 of FIGS. 1A-3D without departing from the scope of the specification. For example, a lid 150 may be used to seal any of the cookware vessels 1000 described above. As another example, the bottom 120 of the outer vessel 100 may not include a depression 124. As a further example, instead of the bottom 120 of the outer vessel 100 including a depression 124 (or in addition to the bottom 120 of the outer vessel 100 including a depression 124), the bottom 220 of the inner vessel 200 may include a depression. An example of this is discussed below.

[0084] FIG. 4 illustrates another example of a cookware vessel 1000 having a depression 224 in the bottom 220 of the inner vessel 200. The cookware vessel 1000 of FIG. 4 may be substantially similar to the cookware vessel 1000 of FIGS. 2A-2D. As such, the cookware vessel 1000 of FIG. 4 may have an outer vessel 100, inner vessel 200, cap 300, and conductive material 310 that may be substantially similar to the outer vessel 100, inner vessel 200, cap 300, and conductive material 310 of FIG. 1 A, discussed above.

[0085] However, unlike the cookware vessel 1000 of FIGS. 2A-2D, the cookware vessel 1000 of FIG. 4 may further (or alternatively) include a depression 224 in the bottom 220 of the inner vessel 200. This depression 224 may fit within the hole 121 in the bottom 120 of the outer vessel 100, thereby assisting in coupling the inner vessel 200 to the outer vessel 100. For example, the depression 224 may allow for (or may further allow for) the stable centering and nesting of the inner vessel 200 within the outer vessel 100 for the steps of laser welding or any other method of attaching the bottoms 120/200 of the inner vessel 200 and outer vessel 100 together. The depression 224 may have a diameter that is not larger than the diameter of the perimeter 122 of the hole 121.

[0086] The depression 224 may be surrounded by a vertical flange 225 in the bottom 220. This vertical flange 225 may allow depression 224 to sit within the hole 121 in the outer vessel 120. The vertical flange 225 may have any height (h). In some examples, the height (h) of the flange 225 may, preferably, be or substantially be (e.g., +/- 0.25 mm) 0.5 mm - 5 mm, and may, more preferably, be or substantially be 1 mm - 3 mm. In some examples, the height (h) of the flange 225 may cause the external surface 224a of the depression 224 to be level with the external surface

120a of the bottom 120, when the depression 224 is positioned within the hole 121. In some examples, the thickness of the material of the depression 224 (i.e., the thickness between internal surface 224b and external surface 224a) may be the same as the thickness of the bottom 120 (i.e., the thickness between internal surface 120b and external surface 120a) of the outer vessel 100. In some examples, the depression 224 may be formed in a mating die after the provision of the hole 121, so that the inner vessel 200 may be forged into the hole 121.

[0087] FIG. 5 is a flow chart that illustrates one example method 2000 for fabricating a cookware vessel, such as the cookware vessel 1000 of FIGS. 1A-4 or any other cookware vessel 100. At step 2001, an outer vessel 100 is formed or provided. The outer vessel 100 may be formed or provided in any manner. For example, the outer vessel 100 may be created or purchased. Examples of the outer vessel 100 are discussed above.

[0088] At step 2002, an inner vessel 200 is formed or provided. The inner vessel 200 may be formed or provided in any manner. For example, the inner vessel 200 may be created or purchased. Examples of the inner vessel 200 are discussed above.

[0089] At step 2003, a hole is formed in a portion of the bottom of one of the inner vessel 200 and the outer vessel 100. That is, the hole may be formed in either a portion of the bottom 220 of the inner vessel 200 or a portion of the bottom 120 of the outer vessel 100. The hole may be formed in any manner. FIGS. 2A-2D illustrate one example of a hole 121 formed in a portion of the bottom 120 of the outer vessel 100. FIGS. 3A-3D illustrate one example of a hole 221 formed in a portion of the bottom 220 of the inner vessel 200. In some examples, the inner vessel 200 and/or the outer vessel 100 may be formed or provided (e.g., steps 2001 and 2002) with the hole already. In such examples, step 2003 may be omitted.

[0090] At step 2004, the inner vessel 200 is inserted into the outer vessel 100. FIGS. 2B and 3B illustrate examples of the cookware vessel 1000 prior to step 2004. FIGS. 2C and 3C illustrate examples of the cookware vessel 1000 following step 2004. The inner vessel 100 may be inserted into the outer vessel 200 in a manner that causes a portion of the external surface 220a of the bottom 220 of the inner vessel 200 to be disposed on a portion of the internal surface 120b of the bottom 120 of the outer vessel 100.

[0091] At step 2005, the inner vessel 200 is attached (or otherwise coupled) to the outer vessel

100. The inner vessel 200 may be attached (or otherwise coupled) to the outer vessel 100 via laser welding, spot welding, brazing, riveting, and the like. FIGS. 2C, 2D, 3C, and 3D illustrate examples of the inner vessel 200 being attached (or otherwise coupled) to the outer vessel 100 via laser welding. [0092] At step 2006, a conductive material 310 is coupled to at least the external surface 120a of the bottom 120 of the outer vessel 100. FIG. 2A illustrates an example of the conductive material 310 being coupled to the external surface 120a of the bottom 120 of the outer vessel 100, and further being coupled to the external surface 220a of the bottom 220 of the inner vessel 200. FIG. 3A illustrates an example of the conductive material 310 being coupled to only the external surface 120a of the bottom 120 of the outer vessel 100. In some examples, the conductive material 310 may be coupled to at least the external surface 120a of the bottom 120 of the outer vessel 100 in a location that is in-between the cap 300 and the at least the external surface 120a. The conductive material 310 may be coupled in any manner. For example, the conductive material 310 may be coupled to at least the external surface 120a of the bottom 120 of the outer vessel 100 via impact bonding. In some examples, step 2006 may result in the conductive material 310 being fused to an annular portion 120D of the bottom 120 of the outer vessel 100 in which the inner vessel 200 has an inner compartment 201.

[0093] In some examples, the step 2006 may occur before or after the inner vessel 200 is attached (or otherwise coupled) to the outer vessel 100 (i.e., step 2005).

[0094] At step 2007, the sidewalls 110 and/or 210 may be trimmed, and/or the rims 130 and 230 may be formed or shaped. This step 2007 may be performed in any manner. In some examples, the inner vessel 200 and/or the outer vessel 100 may be formed or provided (e.g., steps 2001 and 2002) with sidewalls 110/210 already trimmed and the rims 130/230 already shaped or formed. In such examples, step 2007 may be omitted. In examples where step 2007 is performed, the step 2007 may cause the vessel 100/200 to change from a preform version of the vessel to a final version of the vessel. As such, the previous steps in method 2000 may be performed using the preform version of the vessel 100/200, as opposed to the final version of the vessel 100/200.

[0095] At step 2008, the interior and/or exterior of the cookware vessel 1000 may be polished and/or coated. The polishing and/or coating may be performed in any manner. In some examples, step 2008 may be optional.

[0096] Modifications, additions, and/or substitutions may be made to the method 2000 of FIG. 5 without departing from the scope of the specification. For example, one or more steps may be omitted. As another example, one or more steps may be performed simultaneously, or in any other order.

[0097] This specification has been written with reference to various non-limiting and non- exhaustive embodiments or examples. However, it will be recognized by persons having ordinary skill in the art that various substitutions, modifications, or combinations of any of the disclosed embodiments or examples (or portions thereof) may be made within the scope of this specification. Thus, it is contemplated and understood that this specification supports additional embodiments or examples not expressly set forth in this specification. Such embodiments or examples may be obtained, for example, by combining, modifying, or reorganizing any of the disclosed components, elements, features, aspects, characteristics, limitations, and the like, of the various non-limiting and non-exhau stive embodiments or examples described in this specification. In this manner, Applicant reserves the right to amend the claims during prosecution to add features as variously described in this specification.