SELF-HEATING PERSONAL COVERING
Disclosed is a self-heating personal covering that includes a first layer and a second layer that is parallel to and opposite of the first layer, and at least a portion of the second layer is fastened to at least a portion of the first layer. The self-heating personal covering also includes at least one heat source positioned between the first layer and the second layer. The at least one heat source is held in a prescribed position by the first layer and the second layer, and includes a material that undergoes an exothermic reaction upon exposure to oxygen. The at least one heat distributing structure is thermally connected to the at least one heat source.
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This application claims priority to U.S. Provisional Application No. 62/550,300 filed on Aug. 25, 2017, the entire contents of which are incorporated by reference herein.
TECHNICAL FIELDThe present specification generally relates to self-heating blankets or garments and, more specifically, to self-heating blankets or garments having integrated heating sources and materials that disperse heat within in the blanket or garment.
BACKGROUNDPersonal coverings used in medical settings—such as, for example, blankets, garments, gowns, wrappings, and dressings—are often heated using external sources, such as electrical heating, forced air heating, or pre-heating by conduction. However, electrically heated and forced air heated personal coverings are not easily transportable and can be costly to manufacture and maintain. In particular, forced air heated personal coverings require equipment to operate that is expensive and is not easily transported, while the electrical requirements for an electrically heated personal covering may not be available during patient transport. Further, pre-heated personal coverings such as cotton blankets pre-warmed in a warming cabinet will lose heat at an unacceptable rate requiring one to use multiple personal coverings to improve patient comfort and to maintain a patient's body temperature.
Accordingly, a need exists for an alternative self-heating personal coverings that are transportable and provide quick and evenly-distributed heating to the personal covering.
SUMMARYAccording to embodiments, a self-heating personal covering includes a first layer and a second layer that is parallel to and opposite of the first layer, and at least a portion of the second layer is fastened to at least a portion of the first layer. The self-heating personal covering also includes at least one heat source positioned between the first layer and the second layer. The at least one heat source is held in a prescribed position by the first layer and the second layer, and includes a material that undergoes an exothermic reaction upon exposure to oxygen. The at least one heat distributing structure is thermally connected to the at least one heat source.
In at least one embodiment, the at least one heat distributing structure comprises an insulating material. The insulating material may be incorporated into the first layer, or the insulating material may be included as an insulating layer. The insulating layer may comprise channels that permit oxygen to access the heat source. In embodiments comprising an insulating layer, the at least one heat source comprises a first heat source and a second heat source, and a gap comprising air is present in between the first heat source and the second heat source. A portion of the insulating layer is positioned proximate to the first heat source, the second heat source, and the gap such that heat is directed into the gap between the first heat source and the second heat source.
In at least another embodiment, the at least one heat distributing structure comprises a thermally conductive material. In embodiments comprising a thermally conductive material, the at least one heat source comprises a first heat source and a second heat source spaced apart from the first heat source, and the thermally conductive material is positioned between and thermally connected to the first heat source and the second heat source.
In at least another embodiment, the at least one heat distributing structure is a layer of phase change material. The layer of phase change material may be positioned between the at least one heat source and the second layer. In such embodiments, the at least one heat source comprises a first heat source and a second heat source, a gap comprising air is present in between the first heat source and the second heat source, and a portion of the layer of phase change material is positioned proximate to the first heat source, the second heat source, and the gap such that heat is directed into the gap between the first heat source and the second heat source.
Additional features and advantages will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description which follows, the claims, as well as the appended drawings.
It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings illustrate the various embodiments described herein, and together with the description serve to explain the principles and operations of the claimed subject matter.
Reference will now be made in detail to embodiments of self-heating personal coverings, embodiments of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts. In one embodiment, a self-heating personal covering includes a first layer and a second layer that is parallel to and opposite of the first layer, and at least a portion of the second layer is fastened to at least a portion of the first layer. The self-heating personal covering also includes at least one heat source positioned between the first layer and the second layer. The at least one heat source is held in a prescribed position by the first layer and the second layer, and includes a material that undergoes an exothermic reaction upon exposure to oxygen. The at least one heat distributing structure is thermally connected to the at least one heat source. Various embodiments of self-heating personal coverings will be described herein with specific reference to the appended drawings. It should be understood that various elements within one embodiment of a self-heating personal covering may be incorporated in whole or in part to other embodiments of self-heating personal coverings.
As used herein, “personal coverings” includes, but is not limited to blankets, garments, gowns, wrappings, and dressings.
As used herein, “heat distributing structure” includes thermally conductive materials and thermally insulating materials.
A recently explored approach for heating personal coverings is to place self-heating materials into the personal coverings as heat sources. These self-heating materials are activated upon exposure to oxygen and undergo an exothermic reaction, thereby heating the personal covering. However, these self-heating materials can take an unacceptably long time to heat the personal covering to a temperature that will improve patient comfort or to maintain a patient's body temperature at an acceptable level. Also, the exothermic reactions of some self-heating materials may cause the self-heating materials to heat to a temperature that is above the target temperature for a personal covering, which may cause injury to a patient as well as damage to the personal covering. Further, these self-heating materials can create uneven heating and hot spots in the personal covering that leaves some portions of a patient's body overheated and some portions of a patient's body under heated, leading to discomfort.
The present disclosure is directed to a self-heating personal covering that comprises a plurality of heat sources positioned between a first and a second fabric layers. The heat sources may be spaced apart from one another in an array that may be a geometric array of evenly or unevenly spaced apart heat sources. Thermally conductive material may be positioned adjacent, and thermally connected to, one or more heat sources in the personal covering. The thermally conductive material may do one or both of direct heat generated at a heat source in a specific direction—such as, for example, toward a patient—and dissipate heat from the heat source throughout the personal covering.
The self-heating personal covering may be packaged in an air-tight packaging that prevents oxygen from contacting the heat source prior to use, thereby preventing the heat source from undergoing an unwanted exothermic reaction. This packaging configuration allows self-heating person covering to be stored for extended periods of time and allows the user to begin the exothermic reaction of the heat source as desired. Exercising this control over the exothermic reaction through the packaging configuration of the heat source allows the self-heating personal covering to be used on demand in any environment, and the self-heating personal covering will provide heat for several hours after the exothermic reaction of the heat source begins. The vacuum packaging in an air-tight package also compresses the personal blanket and, thus, more blankets can be stored in a given space. This allows more convenient access to the blankets at the bedside, and it also reduces the cost of shipping and storage space.
Because the self-heating personal covering does not require external energy to provide heat and because the self-heating personal covering can provide heat for several hours, the self-heating personal covering may be transported with the patent from the field to an examination room or operating room, and beyond without interruption in heating, the need to transport other machinery, or the need for multiple personal coverings.
Depicted in
With reference to the embodiment depicted in
In the embodiment depicted in
With reference again to
The heat sources 120 may comprise a material that undergoes an exothermic reaction upon exposure to oxygen, such as, for example, upon exposure to ambient atmosphere. Materials commonly used in such heat sources, according to some embodiments, include iron that reacts with oxygen in an exothermic reaction to form iron oxide. Commercially available iron-containing materials used for this purpose include, for example, Pfizer Thermacare® heat wraps, Ready-Heat blanket by TechTrade, and hand warmers by HotHands®, Heat Factory®, HeatMax, Grabber®, Yatktrax®, Little Hotties®, and Ergodyne N-Ferno®. Other materials that, according to one or more embodiments, may be used in the heat sources 120 that undergo an exothermic reaction upon exposure to oxygen include zinc and aluminum, which may be alone or in combination, and react to form zinc oxide and aluminum oxide, respectively, when exposed to oxygen. When using zinc and/or aluminum in the heat sources 120 a carbon may be included as a reduction promoter for oxygen, an alkaline electrolyte may be included as a catalyst to trigger the reaction, and a polytetrafluoroethylene (PTFE) binding agent may be included in the material of the heat sources 120. Commercially available zinc and/or aluminum containing materials used for this purpose include, for example, Exothermix™. However, it should be understood that in embodiments of self-heating personal coverings disclosed and described herein, the heat sources of the self-heating personal coverings may include other materials that undergo an exothermic reaction upon exposure to oxygen in addition to, or as a replacement of, the materials subsequently disclosed.
Because, in embodiments, the heat sources 120 include materials that require exposure to oxygen to begin an exothermic reaction that generates heat, the first layer 110 and the second layer 130 should, in embodiments, provide permeability that allows air and/or oxygen access to the heat sources when desired. In some embodiments, the vapor permeability will be from greater than or equal to 30% to less than or equal to 100%, such as greater than or equal to 35% to less than or equal to 100%, greater than or equal to 40% to less than or equal to 100%, greater than or equal to 45% to less than or equal to 100%, greater than or equal to 50% to less than or equal to 100%, greater than or equal to 55% to less than or equal to 100%, greater than or equal to 60% to less than or equal to 100%, greater than or equal to 65% to less than or equal to 100%, greater than or equal to 70% to less than or equal to 100%, greater than or equal to 75% to less than or equal to 100%, greater than or equal to 80% to less than or equal to 100%, greater than or equal to 85% to less than or equal to 100%, greater than or equal to 90% to less than or equal to 100%, or greater than or equal to 95% to less than or equal to 100%. In other embodiments the vapor permeability is from greater than or equal to 30% to less than or equal to 95%, such as greater than or equal to 30% to less than or equal to 90%, greater than or equal to 30% to less than or equal to 85%, greater than or equal to 30% to less than or equal to 80%, greater than or equal to 30% to less than or equal to 75%, greater than or equal to 30% to less than or equal to 70%, greater than or equal to 30% to less than or equal to 65%, greater than or equal to 30% to less than or equal to 60%, greater than or equal to 30% to less than or equal to 55%, greater than or equal to 30% to less than or equal to 50%, greater than or equal to 30% to less than or equal to 45%, greater than or equal to 30% to less than or equal to 40%, or greater than or equal to 30% to less than or equal to 35%. Materials may have the desired permeability include, for example, paper, polyethylene, polypropylene, polyamide, polyester, polyvinyl chloride, polyvinylidene chloride, polyurethane, polystyrene, saponified ethylene-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, natural rubber, reclaimed rubber, synthetic rubber, and mixtures thereof.
As discussed above, the self-heating personal covering 100 may be placed in an air-tight packaging that restricts access of air and/or oxygen to the self-hating personal covering until the air-tight package is opened. Thereby, a user may determine when to begin the heating of the self-heating personal covering 100, and the self-heating personal covering 100 may be stored for an extended period of time.
Another parameter to consider for materials that may be used in heat sources for the self-heating personal coverings according to embodiments is the time that it takes the material to heat to 40° C. after initial exposure to oxygen. When a patient's body temperature drops below acceptable limits, such as when the patient is in shock or suffering from hypothermia, it is important to increase the patient's body temperature as quickly as possible to avoid negative effects of a reduced body temperature. In addition, patients waiting for surgery often feel cold even if their body temperature is normal, due to their emotional state. Further, these patients may wait as short as 15 minutes for surgery. Thus, every minute that it takes a material to heat to 40° C. can have an effect on patient outcomes, as well as patient satisfaction. As shown in
To use materials as a heat source that quickly heat to 40° C., the heat sources in a self-heating personal covering should be properly spaced apart to prevent overheating of the self-heating personal covering. With reference again to the embodiment depicted in
With reference again to the embodiment depicted in
Although not depicted, the plurality of heat sources 120 may be arranged into an array having a symmetrical geometry pattern of four columns and six rows. In embodiments, the spacing between rows may be greater than or equal to 3.0 inches (7.62 cm), such as greater than or equal to 3.5 inches (8.89 cm), greater than or equal to 4.0 inches (10.16 cm), greater than or equal to 4.5 inches (11.43 cm), or greater than or equal to 5.0 inches (12.70 cm). In some embodiments, the spacing between rows of heat sources 120 in the array of heat sources may be less than or equal to 6.0 inches (15.24 cm), less than or equal to 5.5 inches (13.97 cm), less than or equal to 5.0 inches (12.70 cm), or less than or equal to 4.5 inches (11.43 cm). In embodiments, the spacing between columns of heat sources 120 in the array of heat sources may be greater than or equal to 2.0 inches (5.08 cm), greater than or equal to 2.5 inches (6.35 cm), greater than or equal to 3.0 inches (7.62 cm), or greater than or equal to 3.5 inches (8.89 cm). In embodiments, the spacing between rows of heat sources 120 in the array of heat sources may be less than or equal to 4.0 inches (10.16 cm), less than or equal to 3.5 inches (8.89 cm), or less than or equal to 3.0 inches (7.62 cm).
Because the heat sources 120 are primary drivers of the cost of self-heating personal coverings 100 according to embodiments, having heat sources 120 arranged in a symmetric or asymmetric geometrical array with spacing between the heat sources 120 allows the cost of the self-heating personal coverings 100 to be minimized while still providing adequate heating. However, having such spacing between heat sources 120 in the geometrical array of heat sources can cause heat losses and/or provide uneven distribution of heat across the self-heating personal covering 100. Accordingly, to prevent heat losses and/or provide improved, even distribution of heat generated by the plurality of heat sources 120 in the self-heating personal covering 100, one or more heat distributing structures may be incorporated into the self-heating personal covering 100 proximate to and in thermal connectivity with the heat sources 120. The one or more heat-distributing structures according to one or more embodiments disclosed and described herein include insulating materials, thermally conductive materials, and or phase change materials that may be strategically positioned in proximity to the heat sources 120.
With reference to
It should be understood that although the embodiment depicted in
In the embodiment depicted in
In one or more embodiments, and as shown in the embodiment depicted in
Although embodiments depicted in
In some embodiments, an insulating layer may be positioned only physically between the heat sources 120 and the second layer 130 and the insulating layer will not be present between the air gaps 520 and the second layer 130. This configuration may prevent a patient from being exposed to high temperatures of the heat sources 120 while directing the heat into the air gaps 520, thereby improving even heat distribution within the self-heating personal covering 500.
As used herein, an “insulating” material is a material that conducts heat at a rate lower than or equal to air (which has a thermal conductivity of 0.024 W/(m-K) at 25° C.). Although the insulating material used in the insulating layer 510 or in the first layer 110 of the self-heating personal covering 500 is not limited, in some embodiments the insulating material may be selected from open cell foams, such as, for example, Microcell™ foam, PrimaLoft®, Polarguard®, Climashield®, Thinsulate™, Insultex®, cotton batting, polyester fibers, and combinations thereof. It should be understood that the insulating layer 510 may be mixed with materials that are not insulating materials. Accordingly, in embodiments, the insulating layer 510 may comprise, consist essentially of, or consist of insulating materials.
Additionally, in some embodiments an insulating layer may include a reflective insulating layer, such as, for example, Mylar®, and other polyester films made from stretched polyethylene terephthalate (PET), including Biaxially-oriented polyethylene terephthalate (BoPET). In one or more embodiments, this reflective insulating layer is positioned between the heat source and the layer that is configured to be nearest a patient. For instance, and with reference to
With reference now to the embodiment depicted in
The embodiment depicted in
Although the material used in the thermally conductive material 610 is not limited, in some embodiments the insulating material may be selected from the group consisting of high density polyethylene (HDPE) textiles, Tyvek™ nonwoven materials, metallic foils (such as, for example, aluminum foil and the like), and bladders filled with thermally conductive materials (such as, for example, silicone oil or air), and combinations thereof. As used herein, the term “thermally conductive materials” may also include materials with high specific heat, which, as used herein, includes materials with a specific heat greater than the specific heat of air (1.01 kJ/kg-K) and as close as possible to the specific heat of water (4.18 kJ/kg-K). It should be understood that the thermally conductive material 610 may be mixed with materials that are not thermally conductive. Accordingly, in embodiments, the layer thermally conductive material may comprise, consist essentially of, or consist of thermally conductive materials.
With reference now to the embodiment depicted in
The embodiment depicted in
Additionally, the layer of phase change material 710 between the heat sources 120 and the second layer 130 may prevent the likelihood of a patient overheating by absorbing heat while residing within the phase change temperature. In particular, without being bound to any particular theory, it is believed that the latent heat of fusion or phase change of the layer of phase change material 710 is about an order of magnitude higher than the heat released by non-phase change materials. Accordingly, the phase change materials used in the layer of phase change material 710 provides an energy reserve that may absorb excess heat if the heat sources 120 generate too much heat. Accordingly, in one or more embodiments, phase change materials for use in the layer of phase change material 710 may be selected based upon their latent heat of fusion to regulate the temperature of the self-heating personal covering 700.
Also, according to embodiments, the layer of phase change material 710 may also increase the duration at which the self-heating personal covering 700 provides heating to a temperature of within a desired range (such as about 40° C.). Without being bound to any particular theory, it is believed that this increased duration is accomplished by selecting a phase change material with a melting point around the desired temperature. As the phase change material slowly changes phases with a few degrees of this selected temperature, the self-heating personal covering 700 will likewise maintain a temperature near the selected temperature for a period after the heat sources 120 stop generating heat.
Although the material used in the layer of phase change material 710 is not limited, in some embodiments the material used in the layer of phase change material may be selected from the group consisting of paraffins, capric acid, trimyristin, caprylone, docasyl bromide, camphenilone, and combinations thereof. In one or more embodiments, microencapsulated phase change materials may be used. In some embodiments, the microencapsulated phase change materials may be incorporated into fibers, but in other embodiments the microencapsulated phase change materials may be suspended in a carrier oil, such as, for example, silicone oil.
It should be understood that the layer of phase change material 710 may include a mixture of phase change materials and materials that are not phase change materials. Accordingly, in embodiments, the layer of phase change material 710 may comprise, consist essentially or, or consist of phase change materials.
By using self-heating personal coverings according to embodiments disclosed and described herein that include heat distributing structures proximate to heat sources, heat sources that rapidly heat to about 40° C. may be used. These rapidly-heating heat sources allow self-heating personal coverings according to embodiments disclosed and described herein to heat to a desired temperature much more quickly than conventional self-heating personal coverings. Additionally, by incorporating heat distributing structure proximate to the heat sources, less heat sources need to be incorporated into the self-heating personal covering according to embodiments disclosed and described herein. This decreases the cost, weight, and bulkiness of the self-heating personal coverings. Additionally, the size of the heat sources themselves may be reduced, which allows the self-heating personal coverings according to embodiments disclosed and described herein to have less weight and bulkiness than conventional self-heating personal coverings.
For instance, in embodiments, the thickness of the self-heating personal covering may be less than or equal to 0.100 inches (0.254 cm), such as less than or equal to 0.095 inches (0.241 cm), less than or equal to 0.090 inches (0.229 cm), less than or equal to 0.085 inches (0.216 cm), or less than or equal to 0.080 inches (0.203 cm). Additionally, in one or more embodiments, the weight of the self-heating personal covering is less than or equal to 7.5 g/m2, such as less than or equal to 7.0 g/m2, less than or equal to 6.5 g/m2, less than or equal to 6.0 g/m2, less than or equal to 5.5 g/m2, or less than or equal to 5.0 g/m2.
According to a first clause, a self-heating personal covering comprises a first layer; a second layer parallel to and opposite of the first layer, wherein at least a portion of the second layer is fastened to at least a portion of the first layer; at least one heat source positioned between the first layer and the second layer, wherein the at least one heat source is held in a prescribed position by the first layer and the second layer, and the at least one heat source comprises a material that undergoes an exothermic reaction upon exposure to oxygen to generate heat; and at least one heat distributing structure that is thermally connected to the at least one heat source.
A second clause includes the self-heating personal covering of the first clause, wherein the at least one heat source comprises a plurality of heat sources arranged in a geometrically array, and the geometrical array of the plurality of heat sources comprises spacing between each heat source in the plurality of heat sources.
A third clause includes the self-heating personal covering of the first and second clause, wherein the at least one heat distributing structure is positioned so that a portion of the at last one heat distributing structure is present in the spacing between each heat source in the plurality of heat sources.
A fourth clause includes the self-heating personal covering of any one of the first through third clauses, wherein the at least one heat distributing structure comprises a plurality of heat distributing structures, and at least one heat distributing structure of the plurality of heat distributing structures is present in the spacing between each heat source in the plurality of heat sources.
A fifth clause includes the self-heating personal covering of any one of the first through fourth clauses, wherein the at least one heat distributing structure comprises an insulating material.
A sixth clause includes the self-heating personal covering of the fifth clause, wherein the insulating material is incorporated into the first layer.
A seventh clause includes the self-heating personal covering of the fifth clause, wherein the insulating material comprises an insulating layer that is positioned between the first layer and the at least one heat source.
An eighth clause includes the self-heating personal covering of the seventh clause, wherein the insulating layer comprises material that is permeable to oxygen.
A ninth clause includes the self-heating personal covering of any one of the seventh and eighth clauses, wherein the insulating layer comprises channels that permit oxygen to access the heat source.
A tenth clause includes any the self-heating personal covering of any one of the seventh through ninth clauses, wherein the at least one heat source comprises a first heat source and a second heat source, a gap comprising air is present in between the first heat source and the second heat source, and a portion of the insulating layer is positioned proximate to the first heat source, the second heat source, and the gap such that heat is directed into the gap between the first heat source and the second heat source.
An eleventh clause includes the self-heating personal covering of any one of the first through tenth clauses, wherein the heat distributing structure is a reflective insulating layer.
A twelfth clause includes the self-heating personal covering of any one of the first through eleventh clauses, wherein the at least one heat distributing structure comprises a thermally conductive material.
A thirteenth clause includes the self-heating personal covering of any one of the first through twelfth clauses, wherein the at least one heat source comprises a first heat source and a second heat source spaced apart from the first heat source, and the thermally conductive material is positioned between and thermally connected to the first heat source and the second heat source.
A fourteenth clause includes the self-heating personal covering of any one of the first through thirteenth clauses, wherein the thermally conductive material comprise a member selected from the group consisting of high density polyethylene (HDPE) textiles, metallic foils, bladders filled with thermally conductive materials, and combinations thereof.
A fifteenth clause includes the self-heating personal covering of any one of the first through fourteenth clauses, wherein the at least one heat distributing structure is a layer of phase change material.
A sixteenth clause includes the self-heating personal covering of any one of the first through fifteenth clauses, wherein the layer of phase change material is positioned between the at least one heat source and the second layer.
A seventeenth clause includes the self-heating personal covering of any one of the first through sixteenth clauses, wherein the at least one heat source comprises a first heat source and a second heat source, a gap comprising air is present in between the first heat source and the second heat source, and a portion of the layer of phase change material is positioned proximate to the first heat source, the second heat source, and the gap such that heat is directed into the gap between the first heat source and the second heat source.
An eighteenth clause includes the self-heating personal covering of any one of the first through seventeenth clauses, wherein the layer of phase change material is selected from the group consisting of paraffins, capric acid, trimyristin, caprylone, docasyl bromide, camphenilone, and combinations thereof.
A nineteenth clause includes the self-heating personal covering of any one of the first through eighteenth clauses, wherein the first layer comprises a material that is oxygen permeable.
A twentieth clause includes the self-heating personal covering of any one of the first through nineteenth clauses, wherein the self-heating personal covering is a blanket having a thickness of less than or equal to 0.100 inches and a weight of less than or equal to 7.5 g.
It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Thus it is intended that the specification cover the modifications and variations of the various embodiments described herein provided such modification and variations come within the scope of the appended claims and their equivalents.
Claims
1. A self-heating personal covering comprising:
- a first layer;
- a second layer parallel to and opposite of the first layer, wherein at least a portion of the second layer is fastened to at least a portion of the first layer;
- at least one heat source positioned between the first layer and the second layer, wherein the at least one heat source is held in a prescribed position by the first layer and the second layer, and the at least one heat source comprises a material that undergoes an exothermic reaction upon exposure to oxygen to generate heat; and
- at least one heat distributing structure that is thermally connected to the at least one heat source.
2. The self-heating personal covering of claim 1, wherein the at least one heat source comprises a plurality of heat sources arranged in a geometrical array, and the geometrical array of the plurality of heat sources comprises spacing between each heat source in the plurality of heat sources.
3. The self-heating personal covering of claim 2, wherein the at least one heat distributing structure is positioned so that a portion of the at last one heat distributing structure is present in the spacing between each heat source in the plurality of heat sources.
4. The self-heating personal covering of claim 2, wherein the at least one heat distributing structure comprises a plurality of heat distributing structures, and at least one heat distributing structure of the plurality of heat distributing structures is present in the spacing between each heat source in the plurality of heat sources.
5. The self-heating personal covering of claim 1, wherein the at least one heat distributing structure comprises an insulating material.
6. The self-heating personal covering of claim 5, wherein the insulating material is incorporated into the first layer.
7. The self-heating personal covering of claim 5, wherein the insulating material comprises an insulating layer that is positioned between the first layer and the at least one heat source.
8. The self-heating personal covering of claim 7, wherein the insulating layer comprises material that is permeable to oxygen.
9. The self-heating personal covering of claim 7, wherein the insulating layer comprises channels that permit oxygen to access the at least one heat source.
10. The self-heating personal covering of claim 7, wherein
- the at least one heat source comprises a first heat source and a second heat source,
- a gap comprising air is present in between the first heat source and the second heat source, and
- a portion of the insulating layer is positioned proximate to the first heat source, the second heat source, and the gap such that heat is directed into the gap between the first heat source and the second heat source.
11. The self-heating personal covering of claim 5, wherein the insulating material is a reflective insulating material.
12. The self-heating personal covering of claim 1, wherein the at least one heat distributing structure comprises a thermally conductive material.
13. The self-heating personal covering of claim 12, wherein
- the at least one heat source comprises a first heat source and a second heat source spaced apart from the first heat source, and
- the thermally conductive material is positioned between and thermally connected to the first heat source and the second heat source.
14. The self-heating personal covering of claim 12, wherein the thermally conductive material comprise a member selected from the group consisting of high density polyethylene (HDPE) textiles, metallic foils, bladders filled with thermally conductive materials or air, and combinations thereof.
15. The self-heating personal covering of claim 1, wherein the at least one heat distributing structure is a layer of phase change material.
16. The self-heating personal covering of claim 15, wherein the layer of phase change material is positioned between the at least one heat source and the second layer.
17. The self-heating personal covering of claim 16, wherein
- the at least one heat source comprises a first heat source and a second heat source,
- a gap comprising air is present in between the first heat source and the second heat source, and
- a portion of the layer of phase change material is positioned proximate to the first heat source, the second heat source, and the gap such that heat is directed into the gap between the first heat source and the second heat source.
18. The self-heating personal covering of claim 15, wherein the layer of phase change material is selected from the group consisting of paraffins, capric acid, trimyristin, caprylone, docasyl bromide, camphenilone, and combinations thereof.
19. The self-heating personal covering of claim 1, wherein the first layer comprises a material that is oxygen permeable.
20. The self-heating personal covering of claim 1, wherein the self-heating personal covering is a blanket having a thickness of less than or equal to 0.100 inches and a weight of less than or equal to 7.5 g/m2.
Type: Application
Filed: Aug 23, 2018
Publication Date: Feb 28, 2019
Applicant: Aspen Surgical Products, Inc. (Caledonia, MI)
Inventors: Michael S. Hood (Batesville, IN), Robert J. Lawrence (Grand Rapids, MI), Joel Tunny (Osgood, IN), Logan Cobler (Osgood, IN), Charles A. Lachenbruch (Batesville, IN)
Application Number: 16/110,631