Sealed packaging for solid reactants in self-heating components

Abstract

A sealed package for a self-heating assembly is disclosed, which generates heat to heat a product by causing a liquid reactant to react with a solid reactant in an exothermic manner. The sealed package includes an outer container, a lower support structure (e.g., open-cell foam) located within the outer container, a layer of solid reactant located above the lower support structure and within the outer container, an upper structure (e.g., also open-cell foam) located above the solid reactant and within the outer container, and an upper layer that is permeable to liquid and extends above the upper structure across the originally open top of the outer container.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 927,930, filed on October 30, 2019, entitled Sealed Package for Solid Reactants in a Self-Heating Assembly. The disclosure of the prior application is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates to a sealed package for solid reactants in a self-heating assembly, and more particularly to a sealed package that facilitates the manufacturability of a self-heating assembly of the type that utilizes heat from an exothermic reaction between a liquid reactant and a solid reactant to heat a product. Background Art

[0004] Some self-heating food packages, such as those produced by Tempra Technology, Inc. (applicant of the present application), heat food by exothermic reaction of liquid reactants with granular reactants. It is desirable to improve the handling and manufacturing processes associated with such self-heating food packages while providing safe, efficient and effective heating for the self-heating food packages. Summary of the invention

[0005] On the one hand, a sealed package for a self-heating assembly is disclosed, wherein the self-heating assembly generates heat to heat a product by exothermic reaction of a liquid reactant with a solid reactant. The sealed package includes an outer container, a lower support structure (e.g., an open-cell foam) located within the outer container, a layer of solid reactant located above the lower support structure and within the outer container, an upper structure (e.g., also an open-cell foam) located above the solid reactant and within the outer container, and an upper layer that is permeable to liquid and extends above the upper structure across the originally open top of the outer container. In a typical embodiment, additional solid reactants in granular form are distributed throughout the lower support structure; typically, with a considerable degree of uniformity.

[0006] On the other hand, a method for manufacturing a self-heating container including a sealed package (containing a solid reactant to support an exothermic reaction) is disclosed. The method includes: providing a heater tray; positioning the sealed package inside the heater tray, wherein the sealed package contains a solid reactant and has an upper layer that is permeable to a liquid (e.g., a liquid reactant); positioning a fragile container containing a liquid reactant inside the heater tray; and positioning a product tray inside the heater tray to define a reaction space between the product tray and the heater tray, wherein the reaction space includes the sealed package and the fragile container. In a typical embodiment, the sealed package includes an outer container, a lower support structure (e.g., an open-cell foam) located inside the outer container, a layer of solid reactant located above the lower support structure and located inside the outer container (e.g., in the shape of a solid disk, which is not only rigid in some embodiments, but also fragile and may also have a certain degree of porosity), an upper structure (e.g., also an open-cell foam) located above the solid reactant and located inside the outer container, and an upper layer (e.g., paper) that is permeable to the liquid and extends above the upper structure across the originally open top of the outer container.

[0007] On the other hand, the self-heating assembly comprises: a heater tray, a sealed package inside the heater tray, a frangible container containing a liquid reactant inside the heater tray and above the sealed package, an activation device for activating an exothermic reaction by rupturing the frangible container, and a product tray, wherein the product tray is located in the heater tray to define a reaction space between the product tray and the heater tray. The reaction space comprises a sealed package and a frangible container. The sealed package comprises a solid reactant and has an upper layer permeable to liquid. More specifically, the sealed package has an outer container, a lower support structure in the outer container, a layer of solid reactant located above the lower support structure and in the outer container, an upper structure located above the solid reactant and in the outer container, and an upper layer permeable to liquid and extending across the originally open top of the outer container above the upper structure.

[0008] On the other hand, a method for making a sealed package for a self-heating assembly is disclosed, which generates heat to heat a product by causing a liquid reactant to react with a solid reactant in an exothermic manner. The method includes: providing an outer container (e.g., aluminum having a wall thickness of at least 0.005 inches); filling the bottom of the outer container with a lower support structure (e.g., an open-cell foam); spraying a granular solid reactant (e.g., potassium permanganate particles coated with sodium silicate) into an open-cell network in the lower support structure; providing or forming a non-granular solid reactant disk in the outer container and above the lower support structure; providing an additional structure (e.g., an open-cell foam) above the non-granular solid reactant disk; and sealing the open top of the outer container with paper by adhering or otherwise fixing the paper to the outer container (e.g., adhering or otherwise fixing the paper to an outwardly extending flange of the outer container).

[0009] In some embodiments, one or more advantages exist.

[0010] For example, in the mass production of self-heating components such as those described in detail herein, the sealed packages described herein and the manufacturing techniques involving the sealed packages provide the convenience of handling, for example, a component containing loose particles of solid reactants as a unit (making it in a sealed package). In this regard, the sealed packages described herein are packaged so that they can be easily handled by a machine (or by hand) without leaking, even if they are not handled gently.

[0011] In various embodiments, the sealed packages described herein and the self-heating assemblies utilizing the sealed packages provide safety, reliability, ease of handling during assembly, and the speed of manufacture and use of the self-heating assemblies. In addition, the self-heating assemblies produced have very low heat-up times, which is often an important requirement for example consumer food heaters.

[0012] Other features and advantages will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a perspective view of an embodiment of a self-heating assembly without a cover.

[0014] Figure 2 yes Figure 1 Cross-sectional side view of a self-heating assembly.

[0015] Figure 3 yes Figure 1 Cross-sectional top view of a self-heating component.

[0016] Figure 4 yes Figure 1 Schematic cross-sectional side view of an embodiment of a sealed package within a self-heating assembly.

[0017] Figure 5 For sealed packaging Figure 4 A top perspective view of an embodiment of an outer container.

[0018] Figure 6 is used for Figure 4 A top view of an implementation structure of an upper or lower support structure of an open-cell foam for a sealed package.

[0019] Figure 7 yes Figure 4 A top view of an embodiment of a sealed package.

[0020] Figure 8 yes Figure 4 A perspective view of an embodiment of a sealed package.

[0021] Like reference numerals refer to like elements. DETAILED DESCRIPTION

[0022] The application relates to a self-heating assembly of the following type, wherein two reactants (i.e., a liquid reactant and a solid reactant) contact each other and react in an exothermic manner, thereby heating the product (such as food or beverage) contained therein. In addition, the application relates to a sealed package (comprising the solid reactant), which can be conveniently placed in the self-heating assembly while being sealed during the manufacturing process of the self-heating assembly. This sealed package is convenient for handling solid materials (some solid materials can be in granular form), particularly for handling solid materials during the manufacturing process, because the solid materials remain contained in the sealed package throughout the entire transportation, handling, manufacturing process and thereafter.

[0023] Figures 1 to 3 An exemplary embodiment of a self-heating assembly 100 of the type described below is shown, namely, the type in which two reactants (a liquid reactant and a solid reactant) contact each other and react in an exothermic manner. The self-heating assembly 100 shown is similar in some respects to the self-heating assembly described in prior patent application No. 15 / 076,996 filed by the current patent applicant, Tempra Technologies, entitled Self-Heating Assembly with Distributed Reactants, the entire contents of which are incorporated herein by reference. However, unlike previous self-heating assemblies, the present application Figures 1 to 3 The self-heating assembly 100 in the embodiment has a sealed package 101 in its base, which contains a solid reactant that participates in the exothermic reaction of the self-heating assembly 100. In a typical embodiment, the sealed package 101 containing the solid reactant remains intact during transportation, handling and manufacturing of the self-heating assembly 100, including, for example, when an exothermic reaction occurs.

[0024] The self-heating assembly 100 has two nested trays: a product tray 102 for accommodating a product to be heated (e.g., food, beverage, etc.), and a heater tray 106 coupled to the product tray 102. The product tray 102 is nested inside the heater tray 106, and there is a reaction space 108 between the product tray and the heater tray. In the illustrated embodiment, the reaction space 108 extends from the base of the heater tray 106 to the base of the product tray 102, and from the side of the heater tray 106 to the side of the product tray 102. In a typical embodiment, the product tray is filled with the product to be heated (e.g., food, beverage, etc.), and then sealed (e.g., sealed with a suitable lid, foil, etc.) fixed to and / or adhered to the upper peripheral surface of the self-heating assembly 100.

[0025] Below the product tray, inside the reaction space 108 is a fragile container 110 and a sealed package 101 made of plastics, etc., the fragile container contains a liquid reactant 112 (e.g., fuel), and the sealed package contains a solid reactant. A cutting element 115 extends across the bottom portion of the reaction space 108 between the fragile container 110 (above the cutting element 115) and the sealed package 101 (below the cutting element 115) along a diameter. In the illustrated embodiment, the cutting element 115 comprises an elongated shaft, and the elongated shaft has a plurality of cutting blades 157, which extend radially outward from the shaft in a manner that is roughly parallel to each other. The cutting element 115 is supported by a support surface or a bearing at its opposite end, and these support surfaces or bearings enable the cutting element to rotate in the direction indicated by the arrow "B" around the axis "A" of the elongated shaft.

[0026] Before the exothermic reaction begins, the cutting blades 157 are configured so that they do not pose a risk of cutting into or rupturing the fragile container 110. Figure 2 and Figure 3 An example of such a configuration is shown in , where the cutting blade 157 extends from the elongated axis in a horizontal outward direction between the frangible container 110 and the sealed package 101 .

[0027] One end of the cutting element 115 has a knob 117, which is exposed at the outer surface of the self-heating assembly 100. When the user turns the knob 117, the cutting blade 157 rotates around the axis "A", which causes the cutting blade 157 to cut into the fragile container 110 and break the fragile container, thereby releasing the liquid reactant from the fragile container 110. The upper layer of the sealed package above the solid reactant is permeable to liquid. Since the fragile container 110 is located above the sealed package 101, and since the sealed package 101 has a permeable upper layer, the liquid reactant released from the fragile container 110 flows downward into the sealed package 101 through the permeable upper layer, contacts with the solid reactant, thereby triggering an exothermic reaction.

[0028] The heat generated by the exothermic reaction flows upward through the reaction space 108 to and through the base of the product tray 102 and around and through the sides of the product tray 102 to heat the product contained therein. Thus, the reaction space 108 accommodates the exothermic reaction, and the heat from the exothermic reaction passes through the product tray 102 to heat the product contained therein. In a typical embodiment, the user peels off the lid of the self-heating container after a period of time has passed (e.g., a minute or so) to access and consume (or otherwise use) the heated product inside the product tray 102. In some embodiments, this may take several minutes depending on the design of the heater and the thermal capacity and viscosity of the food or product to be heated inside.

[0029] In a typical embodiment, Figures 1 to 3 As shown, the size of the sealed package 101 is designed to completely fill the bottom of the reaction space 108, leaving almost no empty space around the bottom of the reaction space. This helps to ensure that all liquid reactants flowing out of the frangible container 110 eventually flow into the sealed package 101 to react with the solid reactants contained therein.

[0030] Figure 4 Shows Figures 1 to 3 0047 is a cross-sectional illustration of an exemplary embodiment of a sealed package 101 (containing solid reactants).

[0031] The sealed package 101 shown has a tray-shaped outer container 460, a lower support structure 462 (e.g., an open-cell foam disk, etc.) located within the outer container 460, a layer of non-granular solid reactant 464 (e.g., a solid reactant disk) located above the lower support structure 462 and within the outer container 460, an upper structure 466 (e.g., another open-cell foam disk, etc.) located above the solid reactant 464 and within the outer container 460, and an upper layer 468 (e.g., paper, etc.) that is permeable to liquid (e.g., permeable to liquid reactant) and extends above the upper structure 466 across the originally open top of the outer container 460.

[0032] In the illustrated embodiment, the outer container 460 forms a tray having a flat bottom, a raised edge, and an outwardly extending flange. The upper layer 468 extends across the opening at the top of the tray to seal the contents of the tray therein. More specifically, in the illustrated embodiment, the outwardly extending flange provides a surface to which the upper layer 468 of the sealed package 101 is adhered or fixed in the illustrated embodiment.

[0033] Any of a variety of adhesive materials can be used to adhere the upper layer 468 of the sealed package 101 to the outwardly extending flange of the outer container 460. In a typical embodiment, the adhesive material is configured to remain sticky long enough to allow the cover sheet to be properly placed and pressed down. In various embodiments, the adhesive material is a super glue, hot melt glue, two-part epoxy, Amazing Adhesive, household cement that cures into some kind of elastic adhesive, or any other one of a variety of suitable adhesives. In addition, in typical embodiments, the adhesive material is impermeable to boiling water.

[0034] Furthermore, the adhesive material is typically a material that will remain intact and maintain the upper layer 468 in contact with the outwardly extending flange throughout the life of the sealed package 101 and the self-heating container 100. Thus, in a typical embodiment, the adhesive material should be a material that can withstand (and remain bonded to) exposure to liquid reactants and temperatures associated with an exothermic reaction (e.g., water boiling, about 100°C).

[0035] Any of a variety of other techniques can be used to secure the upper layer 469 of the sealed package 101 in place across the otherwise open top of the outer container 460. For example, in some embodiments, the periphery of the upper layer 469 can be crimped onto an outwardly extending flange of the outer container 460.

[0036] The outer container 460 of the sealed package 101 can be made of any of a variety of solid materials. Typically, the outer container 460 is impermeable to liquids and can withstand the temperatures associated with the exothermic reaction in the self-heating assembly 100. In addition, typically, the outer container 460 is made of a solid material that can be formed into a desired configuration (e.g., Figure 4 The tray-like shape shown) and can resist deformation to at least some extent. An example of such a material is aluminum. Another example of such a material is copper, which is more expensive than aluminum but may be only half as thick as aluminum.

[0037] The material of the outer container 460 (e.g., aluminum) has a thickness. This thickness can vary. However, in some cases, it may be desirable for the aluminum outer container to have a wall thickness of at least 0.005 inches. This minimum thickness can help ensure that even under fairly extreme off-design conditions, localized heating will not damage the heater tray 106, which is typically plastic. The thermal conductivity associated with aluminum having at least a minimum thickness helps prevent such damage from occurring. In some embodiments, the aluminum tray can have a wall thickness between 3 and 4 millimeters.

[0038] The height of the outer container 460 (ie, the distance between the bottom and the flange) can of course vary. In various embodiments, the height of the outer container 460 can be between about a quarter inch and 1 inch.

[0039] The lower support structure 462 is located at the bottom of the outer container 460. In a typical embodiment, the lower support structure 462 is disc-shaped and made of open-cell foam or another cellular or porous material, and a liquid (e.g., a liquid reactant) can flow through or pass through the lower support structure. In the illustrated embodiment, the size of the lower support structure 462 is designed to cover the entire inner bottom surface of the outer container 460. In addition, in the illustrated embodiment, the side edges of the lower support structure 462 are in contact with the inner sidewall of the outer container 460 around the entire perimeter of the outer container.

[0040] In certain embodiments, some solid reactants in granular form may be dispersed on lower support structure 462 and supported, for example, on top of and / or within openings or pores of lower support structure 462. In these embodiments, the solid granular reactants may be substantially uniformly distributed on lower support structure 462.

[0041] Lower support structure 462 is generally configured to facilitate liquid flow (e.g., flow of liquid reactants) through lower support structure 462. This enables any liquid reactants that reach, for example, the periphery of lower support structure 462 to flow through lower support structure 462 and reach any particulate solid reactants that may be dispersed within and / or above lower support structure 462, as well as reach the bottom surface of the layer of solid reactants 464 located directly above lower support structure 462. In typical embodiments, this helps ensure that the exothermic reaction occurs quickly and increases the likelihood that more of the particulate reactants will actually react.

[0042] In a typical embodiment, lower support structure 462 has sufficient structural integrity to physically support any components located on top of lower support structure 462 without excessive compression, which may impair the ability of the lower support structure to transport liquid reactants to the bottom surface of the granular solid reactants within or above lower support structure 462 and the layer of solid reactants 464 located directly above the lower support structure. In the illustrated embodiment, for example, lower support structure 462 is strong enough to physically support any granular solid reactants above or within lower support structure 462, the layer of non-granular solid reactants 464 above lower support structure 462, and upper structure 466 above the layer of non-granular solid reactants 464. Typically, lower support structure 462 achieves this with no more than very little, if any, significant compression (e.g., less than about 10% of its thickness).

[0043] In the illustrated embodiment, the height of the lower support structure 462 (e.g., from its lower surface in contact with the bottom of the outer container 460 to its upper surface opposite and above its lower surface) is about 1 / 3 of the height of the outer container 460. Of course, this can vary considerably, and the lower support structure 462 can have any height from about 1 / 16 inch (or less) to 1 / 2 inch (or more). In an exemplary embodiment, an approximately 1 / 8 inch thick open cell plastic foam disk can be placed on the bottom of the aluminum tray before the granular material is poured into the tray. Of course, this provides a fuel flow path for the bottom side of the block cast particles during operation of the self-heating container 100.

[0044] The size of individual granular solid reactant particles that may be dispersed on and throughout the lower support structure 462 may also vary. The size of some particles may be configured so that these particles are located on top of the open-cell foam material of the lower support structure 462. The size of some particles may be configured to be suitable for placement in the open cells or pores of the lower support structure 462. In some embodiments, the size of individual particles may vary so that some particles are located on top of the lower support structure 462, while some particles are located in the open cells or pores of the lower support structure 462.

[0045] In some embodiments, the particles are very small compared to the holes or pores of the lower support structure 462 (which can have a nominal pore count, e.g., between about 25 and 45 pores per inch (e.g., 30 ppi)) so that the particles fall into the holes or pores and at least some of the particles pass through the holes or pores to the bottom (or near the bottom) of the lower support structure 462. It may be desirable to have particles at or near the bottom of the lower support structure 462 because once the liquid reactant reaches the particles (e.g., by flowing down to the bottom of the chamber), the particles will begin to react. The reaction that occurs causes boiling, which helps wet the bottom surface of the layer of reactant particles and non-granular solid reactant 464 that are located higher in the lower support structure 462.

[0046] In the embodiment shown, the layer of non-granular solid reactant 464 is located above the lower support structure 462 and is in direct physical contact with the lower support structure. The layer of this solid reactant 464 is in the form of a solid disk with a flat top surface, a flat bottom surface and a cylindrical side. The layer of non-granular solid reactant 464 has a cake-like consistency generally, and therefore tends to keep a disk-like structure under normal processing conditions. In addition, in a typical embodiment, the solid bonding particles are rigid and strong enough to be processed, but are easily broken and fragile. In addition, in a typical embodiment, the layer of non-granular solid reactant 464 keeps its disk-like structure generally, until it is exposed to the liquid reactant with which exothermic reaction occurs. The reaction begins to destroy the disk-like structure of the layer of non-granular solid reactant 464. As the reaction proceeds, the layer of non-granular solid reactant 464 dissolves gradually, until little or no solid reactant remains.

[0047] In some embodiments, the solid reactant is an oxidant (e.g., potassium permanganate, which may be coated with sodium silicate) in either granular or non-granular form, and the liquid reactant is a reducing agent (e.g., aqueous glycol fuel). Of course, other types of reactants may also be used instead. In this regard, many oxidants are capable of producing appropriate energy when reacting with the corresponding fuel. Typical oxidants include oxidants composed of alkali metal salts of manganese and chromium oxides. These oxidants include compounds such as potassium permanganate and potassium chromate. Other suitable oxidants are pyridinium dichromate, ruthenium tetroxide and chromic acid, as well as many other oxidants. Preferably, the oxidant includes an alkali metal salt of permanganate. The corresponding fuel suitable for the exothermic chemical reaction is generally an organic compound. Particularly suitable organic compounds are alcohols. Alcohols are easily oxidized to carbonyl-containing compounds by the above-mentioned oxidants. The alcohol may be a primary alcohol, preferably a polyol containing at least two hydroxyl groups. Such polyols are also easily oxidized to aldehydes and carboxylic acids. This oxidation of the polyol and the simultaneous reduction of the oxidant are usually accompanied by the release of a large amount of heat energy. A preferred fuel is glycerol.

[0048] In a typical embodiment, the layer of non-granular solid reactant 464 is in contact with and / or pressed against the upper surface of the lower support structure 462, which helps to maintain a typical substantially uniform distribution of the granular solid reactant on top of the lower support structure 462, at least until the layer of non-granular solid reactant 464 begins to dissolve.

[0049] There are various ways to form a layer of non-granular solid reactant 464. In a kind of such exemplary method, solid reactant (for example, potassium permanganate coated with sodium silicate) can be supplied to a cylindrical container as a powder or in a granular form, and then exposed to moisture (for example, in a humid environment or by using a humidifier, that is, a collection of components that produce moisture). In an exemplary embodiment, moisture causes sodium silicate to absorb moisture from a humid environment, and powdery or granular solid reactants are combined into a disc (puck) or a disc-shaped structure. Then, the disc-shaped solid reactant is usually removed from moisture and dried. In some embodiments, drying can be accelerated by exposing the disc-shaped solid reactant to a heating environment (for example, in an oven) for a period of time. The heating environment can be a relatively low temperature (for example, 120 ° F), and the time period can be, for example, between 1 hour and 4 hours. However, higher temperatures and shorter time can certainly be used to dry the humidified disc.

[0050] The upper structure 466 in the outer container 460 is disc-shaped and is made of an open-cell foam or another cellular or porous material through which a liquid (e.g., a liquid reactant) can flow or pass. In some embodiments, the upper structure 466 is made of the same material as the lower support structure 462. However, this is not necessarily the case. For example, in some embodiments, the openings or pores in the upper structure 466 can be larger than the openings or pores in the lower support structure 462. In some embodiments, the openings or pores in the upper structure 466 can be smaller than the openings or pores in the lower support structure 462.

[0051] In the illustrated embodiment, the upper layer 468 extends across and covers the open top of the outer container 460. More specifically, the periphery of the bottom surface of the upper layer 468 is fixed to the upper surface of the outwardly extending flange portion of the outer container 460. In some embodiments, the upper layer can be fixed using a hot melt adhesive or any other type of adhesive or fixing technology (which can keep the upper layer 468 in contact with the outer container 460 and seal against the outer container during the entire service life of the self-heating component 100). When the upper layer 468 is so adhered to the outwardly extending flange portion of the outer container 460, the upper layer 468 and the outer container 460 together seal the internal compartment of the self-heating component 100, thereby preventing any loose powders, etc. from escaping from the self-heating component 100.

[0052] In a typical embodiment, the upper layer 468 is paper. However, in various embodiments, the upper layer 468 can be another material. The other material should be liquid permeable and able to withstand the operating conditions associated with the self-heating assembly 100.

[0053] The sealed package 101 may be assembled in a variety of ways.

[0054] One embodiment of the assembly process includes providing components of the sealed package, which include an outer container or material (such as aluminum) to be formed into the outer container, one or more pieces of open-cell foam or another cellular or porous material to form or serve as a lower support structure and an upper structure, solid reactants (usually provided in granular form), paper (or some other material that is permeable to liquid and suitable for application) to form an upper layer, and an adhesive material.

[0055] If the sheet of aluminum or other material is not provided in the shape of a tray, the sheet of aluminum or other material is formed to form a tray, typically a tray having an upper flange extending outwardly, such as Figure 1 shown.

[0056] Next, if desired, open cell foam or another cellular or porous material is cut to fit snugly into the bottom of the outer container to serve as the lower support structure. The lower support structure is then positioned on the bottom of the outer container.

[0057] Next, the granular reactant is poured into the top of the lower support structure in the outer container, typically filling at least some portion of the openings in the lower support structure.

[0058] Next, form the non-granular solid reactant dish.This non-granular solid reactant dish can form in various ways.For example, the non-granular solid reactant dish can form in the outside of the external container, and fall into the top of the granular material in the external container, and this granular material has been poured into the top of the lower support structure and enters the lower support structure.Perhaps, the non-granular solid reactant dish can be formed on the top of the granular material in the external container, and this granular material has been poured into the top of the lower support structure and enters the lower support structure.

[0059] There are many methods to form a non-granular solid reactant disk outside the outer container. For example, the solid reactant (for example, potassium permanganate coated with sodium silicate) can be supplied to a cylindrical container as a powder or in a granular form, and is placed on a support above the water surface in the container. This exposes the granular material to moisture. Moisture makes sodium silicate absorb moisture from a humid environment, and combines the powdery or granular solid reactant into a disc-like or disc-like structure. Then, the disc-like solid reactant is removed from moisture and allowed to dry. In some embodiments, drying can be accelerated by exposing the disc-like solid reactant to a heated environment (for example, in an oven) for a period of time. If this method for forming a non-granular solid reactant disk is utilized, then a disk can be prepared before assembling one or more sealed packages, which is actually to prepare a plurality of disks.

[0060] The non-granular solid reactant disk can be formed on the top of the granular material inside the outer container by various ways, and the granular material has been poured on the top of the lower support structure and enters the lower support structure. For example, the extra granular material can be poured into the top of any granular material that may have been poured into the lower support structure in the outer container. In a typical embodiment, this extra granular material may be enough to form a layer with the same thickness as the thickness of the lower support structure or at least substantially similar thickness. Next, the outer container containing the granular material inside the lower support structure and the lower support structure is placed in a humid environment. This exposes the granular material to moisture. Moisture makes sodium silicate absorb moisture from a humid environment, and combines powdered or granular solid reactants into a disc-shaped or disc-shaped structure. This combination can also make the solid reactant be combined to the inner side wall of the lower support structure and the outer container. Then, the outer container is removed from moisture so that the granular material inside the outer container can be dried. In some embodiments, drying can be accelerated by exposing the outer container to a heated environment (e.g., in an oven) for a period of time.

[0061] The bonding helps ensure that the non-granular discs do not move around the reaction chamber or in a pile to one side of the reaction chamber, for example, when the container is tipped over during shipping or storage. In a typical embodiment, the foam helps prevent the powder from moving.

[0062] Next, if necessary, open-cell foam or other cellular or porous material is cut to fit snugly over the solid reactant disk in the outer container as a superstructure. The superstructure is then positioned over the non-granular solid reactant disk inside the outer container.

[0063] Next, if necessary, paper (or other liquid-permeable and applicable materials for application) is cut to extend above the open top of the outer container. The material is then attached to the outer container, usually by using a hot melt adhesive with the periphery of the lower surface of the paper bonded to the outwardly extending flange of the outer container. In a typical embodiment, the hot melt adhesive is applied to the entire periphery of the paper / flange interface, and no rupture occurs. Therefore, this material is used as the upper strata of the outer container, and the above-mentioned solid reactant and foam are sealed in a sealed package.

[0064] Having a preassembled sealed package 101 (i.e., a sealed package 101 that has been assembled before manufacturing the self-heating component 100, for example, as described above) is conducive to the manufacturability of the self-heating component 100. In this regard, a sealed package 101 (or a plurality of sealed packages 101) can be manufactured, and when the self-heating component 100 is being manufactured, one of the sealed packages 101 can be simply dropped into the base of the self-heating component 100 at an appropriate point in the manufacturing process. This simplifies the handling of solid reactants (particularly granular solid reactants) in the self-heating component 100 manufacturing process. For example, in the absence of a preassembled sealed package 101, there is a great risk that the granular reactants may overflow or rise, causing confusion, and / or ultimately be located in an undesirable part of the self-heating container. However, in the case of a preassembled sealed package, accommodating and controlling the granular reactants is simplified and significantly improved.

[0065] To activate the heating function in the self-heating assembly, the user will manipulate the handle 117 to rotate the shaft 115 about the axis "A" in the direction indicated by the arrow "B". This will cause the cutting blade 157 to move into the frangible container 112 and ultimately cut or break the frangible container 112. In the example shown, to manipulate the handle in this manner, the user can first lower the handle 117 to the activation position (e.g., by swinging the handle about the hinge 121), and then rotate the handle about the axis "A" in the direction indicated by the arrow "B".

[0066] As the liquid fuel is released from the frangible container 112, the liquid fuel flows in a downward direction toward the bottom of the self-heating assembly 100. Since the sealed package 101 is located at the bottom of the self-heating container 100 and fills (or at least substantially fills) the bottom of the self-heating container 100, most, if not all, of the liquid fuel released from the ruptured frangible container 112 passes through the upper layer 468 of the sealed package 101 and enters the sealed package 101.

[0067] The liquid fuel flowing into the sealed package 101 flows through the open pore structure of the upper structural element 466 inside the sealed package 101. The liquid fuel tends to be distributed on the upper surface of the non-granular solid reactant 464 disk by the open pore structure of the upper structural element 466. Wherever the liquid fuel contacts the non-granular solid reactant 464 disk, the liquid fuel reacts exothermically with the non-granular solid reactant.

[0068] Some of the liquid fuel that flows into the sealed package 101 also flows to the bottom of the sealed package 101, where it contacts the granular solid reactant distributed throughout the open pore network of the lower support structure 462. Wherever the liquid fuel contacts the granular solid reactant, the liquid fuel reacts exothermically with the granular solid reactant.

[0069] In a typical embodiment, the heat from the exothermic reaction causes the liquid (particularly the liquid at the bottom of the sealed package 101) to boil. The boiling produces turbulence, which tends to cause the liquid fuel to gradually move upward from the bottom of the sealed package 101 through the perforated structure of the lower support structure 462, to contact the increasing granular solid reactants embedded in the lower support structure 462. Eventually, the liquid level (and the boiling of the liquid) at the bottom of the sealed package 101 increases to the point where the liquid fuel can reach the bottom of the non-granular solid reactant 464 dishes. This causes the exothermic reaction to occur at the surface bottom of the non-granular solid reactant dish. At this point, in a typical embodiment, heat is generated by the exothermic reaction that occurs above and below the non-granular solid reactant 464 dishes. This generates a large amount of heat very quickly to heat any product (such as food, beverage, etc.) in the product tray 102.

[0070] Figure 5 1 is a perspective view of an exemplary embodiment of a portion of an outer container 460 of a sealed package 101. The outer container 460 is shown having a flat base, side walls extending upward from the base (and may flare slightly outward), and flanges extending in an outward direction from the upper ends of the side walls. The outer container is shown to be made of aluminum.

[0071] Figure 6 is a top view of an exemplary embodiment of an upper or lower support structure (466 or 462) for sealing package 101. The structure shown is an open cell foam and has an overall shape of a disc.

[0072] Figure 7 yes Figure 4 A top view of an outer container having a disk of foam and an exemplary solid reactant (464) disk therein.

[0073] Figure 8 is a perspective side view of an exemplary sealed package 101. The sealed package 101 has Figure 4 An exemplary outer container 460 and a piece of paper extending over the open top of the outer container 460 and serving as an exemplary upper layer 468 of the sealed package 101.

[0074] A number of embodiments of the present invention have been described, however, it will be appreciated that various modifications can be made without departing from the spirit and scope of the invention.

[0075] The self-heating assembly described herein is but one example of a self-heating container in which a sealed package may be used.

[0076] For example, in Figures 1 to 3In the illustrated embodiment, the frangible container is located directly below the base of the product tray, the cutting element is located directly below the frangible container, and the sealed package (containing the solid reactant) is located directly below the cutting element. Other relative arrangements are also possible. For example, in some embodiments, the cutting element can be located above or on one side of the frangible container. In addition, the cutting element can be arranged in a manner similar to that of the frangible container. Figures 1 to 3 The shaft with the cutting blade shown is in a different form. For example, the cutting element may include one or more spikes that move in an axial manner to pierce the frangible membrane.

[0077] The size and relative configuration of the inner product tray and the outer heater tray can vary widely. Thus, the size and shape of the chamber between the inner product tray and the outer heater tray can also vary. The size and shape / configuration of the sealed package can vary widely. Other aspects of the sealed package can also vary.

[0078] The sealed package can have any one of various shapes. For example, in some embodiments, the shape can be the shape of a bowl or a plate. In other embodiments, the sealed package can be an oval or any other shape.

[0079] In some embodiments, all solid reactants may be in granular form, with none of the solid reactants being the disc-shaped, non-granular configurations described herein. In some of these cases, the amount of granular solid reactants may be sufficient to fill approximately 1 / 3 of the sealed package.

[0080] The lower support structure and / or the upper structure can take any of a variety of different forms. For example, in various embodiments, either or both of the lower support structure and the upper structure can be open-cell foam, non-woven material (e.g., felt), filter pads, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes packed tightly together, layered tissue (e.g., with particles packed between layers), etc. In some embodiments (including Figures 1 to 3 In the embodiment shown), both layers are open cell foam.

[0081] In a typical embodiment, some particles are held in place by the lower support structure itself. For example, in the case of open-cell foam, some particles may be positioned or wedged into the open cells of the foam and held in place by being so wedged. Additionally, in a typical embodiment, the lower support structure is in close physical contact with its surrounding components (e.g., the side walls of the heater tray, the bottom surface of the heater tray, etc.) before the heater is activated. This arrangement can help prevent any loose particles (e.g., particles that are not tightly held in place by the support structure itself) from migrating within the self-heating assembly (e.g., above, below, or to the side of the support structure).

[0082] The activation device that activates the reaction by rupturing the frangible container is described as an external knob connected to an internal shaft having cutting blades that extend from the shaft generally parallel to each other in a radially outward direction. However, the activation device can take any of a variety of different forms. For example, in various embodiments, the activation device can be a sliding element having cutting blades that move into the frangible container when slid, or a button that can be pressed to push a spike or other cutting blade into the frangible container, or a pair of surfaces that can be pushed toward each other to squeeze the frangible container until the frangible container ruptures, or other components. For example, even if Figure 2 and Figure 3 The activation device shown in can also be different, having more or fewer cutting blades, having longer or shorter or differently shaped cutting blades, having different types of external knobs, etc.

[0083] In an exemplary embodiment, the first liquid reactant is or comprises a fuel (e.g., a polyol fuel, such as ethylene glycol or glycerine), and the second granular reactant is or comprises an oxidant (e.g., an alkali metal permanganate, such as potassium permanganate). In some exemplary embodiments, the first liquid reactant is or comprises water, and the second granular reactant is or comprises calcium oxide. Any group of reactants can be used, as long as one of them is a liquid or slurry, which can flow through the upper layer of the sealed package and flow through the upper structure and the lower support structure to approach another reactant (i.e., the granular and / or solid disk-shaped reactant in the sealed package). In a specific embodiment, the reactant is potassium permanganate and glycerol aqueous solution.

[0084] In a typical embodiment, the particles of the solid reactant will be coated with graded thicknesses of sodium silicate (water glass). Since sodium silicate dissolves slowly in hot water, and water may be the main component of the liquid, varying the thickness of the sodium silicate can adjust the time it takes for the potassium permanganate particles to react with the polyol fuel. However, in some embodiments, sodium silicate is not included.

[0085] The relative and absolute sizes of the various subcomponents may vary widely. Various materials may be suitable for forming each subcomponent.

[0086] The one or more support structures may be virtually any type of structure capable of performing the functions described herein and attributed to the one or more support structures.

[0087] In various embodiments, various types of tamper-evident protection may be provided. Generally speaking, tamper-evident protection provides an indication or barrier to entry that, if broken or missing, can reasonably be expected to provide visible evidence to the consumer that the product has been tampered with. Examples of tamper-evident protection may include, for example, a removable label, a plastic wrap around the exterior of the knob assembly, and the like.

[0088] Various methods can be used to make non-granular solid reactant layers. In an exemplary method, after an open top outer container (having a lower support structure and an inner granular reactant) is placed in a water vapor saturated atmosphere for about 12 hours, the particles are formed into a rigid cake. These particles are then dried in an oven. Then a second open-cell foam disk is placed on the top of the particle mass to provide a fuel flow path at the top, and a lightweight unglazed paper disk is adhered to the top to complete packaging. Intentionally using the fuel flow path on the top of the particle cake helps to prevent both paper and plastic fuel bags from sealing all or part of the particle bed during the initial fuel injection.

[0089] It should be understood that any relative terms used herein, such as "upper," "lower," "above," "below," "front," "rear," etc., are intended solely to clearly describe the specific embodiments being discussed and are not intended to limit the scope described herein to require a specific position and / or orientation. Therefore, such relative terms should not be interpreted as limiting the scope of the present application. In addition, the term "substantially" and similar words (e.g., approximately) are used herein. Unless otherwise indicated, substantially and similar words should be broadly interpreted as completely and nearly completely (e.g., for measurable quantities, this may mean, for example, 99% or more, 95% or more, 90% or more, or 85% or more).

[0090] In some embodiments, the granular reactants are distributed or dispersed throughout the lower support structure in a substantially uniform manner. This means that the particle density in a plurality of equal volumes of the support structure (e.g., cubic centimeters) does not vary by more than a certain amount (e.g., 10%, 15%, 20%, etc.). In addition, in typical embodiments, the lower support structure supports and substantially maintains the distribution of the granular reactants throughout the lower support structure before and during the exothermic chemical reaction. In some embodiments, this may mean preventing the particles (of the granular reactants) from moving to maintain a substantially uniform distribution.

[0091] The self-heating assembly may be used to heat any of a variety of different products including food, beverages or non-edible goods.

[0092] Although this specification contains many specific implementation details, these should not be interpreted as limitations on the scope of any invention or what may be claimed, but rather as descriptions of specific features of specific embodiments of specific inventions. Certain features described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, the individual features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable subcombination. In addition, although these features may be described as working in certain combinations and even initially claimed as such, in some cases, one or more features from the claimed combination may be excluded from the combination, and the claimed combination may be directed to a subcombination or a variation of a subcombination.

[0093] Similarly, although operations and / or processes are disclosed herein as occurring in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all indicated operations be performed to achieve the desired results. In some cases, multitasking or parallel processing may be advantageous.

[0094] Other implementations are within the scope of the following claims.

Claims

1. A sealed package for a self-heating assembly, the sealed package comprising: outer container; a lower support structure, the lower support structure being located within the outer container; a layer of solid reactant located above the lower support structure and within the outer container; an upper structure, the upper structure being located above the solid reactants and within the outer container; as well as an upper layer that is liquid permeable and extends over and seals the otherwise open top of the outer container above the upper structure, Wherein, the lower support structure comprises a material selected from the following group: open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and stacked tissue paper.

2. The sealed package according to claim 1, wherein: The layer of solid reactant above the lower support structure is a layer of non-granular solid reactant.

3. The sealed package according to claim 1, wherein: The sealed package also includes a granular solid reactant distributed throughout the lower support structure.

4. The sealed package according to claim 3, wherein: The upper structure comprises a material selected from the group consisting of open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and laminated tissue paper.

5. The sealed package according to claim 1, wherein: The outer container is made of aluminum and has a minimum wall thickness of 0.005 inches.

6. The sealed package according to claim 1, wherein: The solid reactant is an alkali metal salt of an oxide of manganese or chromium.

7. The sealed package according to claim 1, wherein: The solid reactant is selected from the group consisting of potassium permanganate, potassium chromate, pyridinium dichromate, ruthenium tetroxide and chromic acid.

8. The sealed package according to claim 1, wherein: The individual particles of the solid reactant are coated with sodium silicate.

9. The sealed package according to claim 1, wherein: The non-woven material is felt.

10. A method of making a self-heating container, the method comprising: A heater tray is provided; positioning a sealed package within the interior of the heater tray, wherein the sealed package contains a solid reactant and has a liquid permeable upper layer; positioning a frangible container containing a liquid reactant within the heater tray; and positioning a product tray within the heater tray to define a reaction space between the product tray and the heater tray, wherein the reaction space includes the sealed package and the frangible container, Wherein, the sealed package comprises: outer container; a lower support structure, the lower support structure being located within the outer container; a layer of solid reactant located above the lower support structure and within the outer container; an upper structure positioned above the solid reactants and within the outer container; and an upper layer that is liquid permeable and extends over and seals the otherwise open top of the outer container above the upper structure, and Wherein, the lower support structure comprises a material selected from the following group: open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and stacked tissue paper.

11. The method according to claim 10, wherein: The layer of solid reactant above the lower support structure is a layer of non-granular solid reactant.

12. The method according to claim 10, wherein: The sealed package also includes a granular solid reactant distributed throughout the lower support structure.

13. The method according to claim 12, wherein: The upper structure comprises a material selected from the group consisting of open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and laminated tissue paper.

14. The method according to claim 10, wherein: The outer container is made of aluminum and has a minimum wall thickness of 0.005 inches.

15. The method according to claim 10, wherein: The solid reactant is an alkali metal salt of an oxide of manganese or chromium, and Wherein, the liquid reactant is an organic compound.

16. The method according to claim 10, wherein: The solid reactant is selected from the group consisting of potassium permanganate, potassium chromate, pyridinium dichromate, ruthenium tetroxide and chromic acid, and Wherein, the liquid reactant is alcohol.

17. The method according to claim 10, wherein: The individual particles of the solid reactant are coated with sodium silicate.

18. The method according to claim 10, wherein: The method further comprises: Activation means is provided for activating a reaction by rupturing the frangible container in the self-heating container.

19. The method according to claim 10, wherein: The method further comprises: providing a product to be heated in the product tray; and The product tray is sealed.

20. A self-heating assembly comprising: Heater tray; a sealed package located inside the heater tray, wherein the sealed package contains a solid reactant and has an upper layer that is permeable to a liquid; a frangible container located within the heater tray and above the sealed package and containing a liquid reactant; activation means for activating an exothermic reaction by rupturing the frangible container; and a product tray located within the heater tray to define a reaction space between the product tray and the heater tray, wherein the reaction space includes the sealed package and the frangible container, Wherein, the sealed package comprises: outer container; a lower support structure, the lower support structure being located within the outer container; a layer of solid reactant located above the lower support structure and within the outer container; an upper structure positioned above the solid reactants and within the outer container; and an upper layer that is liquid permeable and extends over and seals the otherwise open top of the outer container above the upper structure, and Wherein, the lower support structure comprises a material selected from the following group: open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and stacked tissue paper.

21. The self-heating assembly of claim 20, wherein: The layer of solid reactant above the lower support structure is a layer of non-granular solid reactant.

22. The self-heating assembly of claim 20, wherein: The upper structure comprises a material selected from the group consisting of open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and laminated tissue paper.

23. The self-heating assembly of claim 20, wherein: The sealed package also includes a granular solid reactant distributed throughout the lower support structure.

24. The self-heating assembly of claim 20, wherein: The outer container is in direct physical contact with the inner surface of the plastic heater tray, and Wherein, the outer container is made of aluminum and has a minimum wall thickness of 0.005 inches.

25. A method of making a sealed package for a self-heating assembly that generates heat to heat a product by exothermic reaction of a liquid reactant with a solid reactant, the method comprising: Provide external containers; placing a lower support structure inside the outer container and on a bottom surface of the outer container, wherein the lower support structure comprises a material selected from the group consisting of open cell foam, non-woven material, filter pad, quilted tea bag material, deep flocking, permeable honeycomb, deep pile carpet, short tubes tightly packed together, and stacked tissue paper; distributing a granular solid reactant into the open pore structure of the lower support structure; providing or forming a disk of non-particulate solid reactants in the outer vessel above the lower support structure; providing an additional structure above the non-granular solid reactant disk, wherein the additional structure has an open-pore structure; and The open top of the outer container is sealed with the paper by securing the paper to the outer container.

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