[0001] The present invention relates generally to the field of warming or heat retaining devices and more particularly, but not by way of limitation, to an apparatus and method for warming extremities, such as the feet.

BACKGROUND

[0002] Extremities, such as feet, legs, hands and arms, are difficult to keep warm in cold or cool environments. Certain individuals suffer from chronic conditions that result in cold extremities, even in temperate or normal temperature environments. Other medical conditions, such as diabetes and peripheral diseases, may result in reduced blood flow to the extremities, further exacerbating the problem of cold extremities (hereinafter "cold feet") . Further, fashion choices may result in footwear that does not adequately provide thermal protection to prevent cold feet.

[0003] Electric heaters, including both "plug-in" electric heaters and battery powered electric heaters, can be expensive, cumbersome to transport, and often are not allowed in office or other environments because they are dangerous and may be considered fire hazards. Electric blankets suffer from many of these same disadvantages, and some believe the electromagnetic energy generated by electric blankets produce adverse health effects . SUMMARY

[0004] The present disclosure provides an apparatus and method for warming (or maintaining warmth in) extremities, such as a foot warmer, that effectively, conveniently and comfortably retains warmth surrounding the extremities, such as the feet. In one embodiment, a foot warmer is provided that includes an opening and an inner volume that is at least partially lined with a soft inner fabric layer, a radiant barrier positioned at least partially or fully over where a user's feet would reside within the inner volume, and an outer fabric provided primarily on the exterior of the foot warmer. Various embodiments and aspects are described herein.

[0005] The present disclosure also includes the method of preheating the foot warmer by placing it in a clothes dryer or using, for example, a hair dryer to impart warm air into the inner volume or adjacent the foot warmer to pre-heat or "prime" the foot warmer. The radiant barrier is then used to assist with retaining the radiant heat that is now present within the inner volume, and that is generated by a user's feet when placed within the foot warmer and/or the warm air imparted into the inner volume.

[0006] Another method of the disclosure involves a foot warmer that does not include a radiant barrier positioned below the user's feet, but does include a radiant barrier layer positioned above the user' s feet when the foot warmer is in normal use. If the user's feet ever become too warm, the flexible nature of certain embodiments of this invention allows the foot warmer to be flipped or turned over so that the top portion that resided above the user' s feet is now positioned below the user's feet, and rising radiant heat is thus able to more readily escape the foot warmer because the radiant barrier layer is no longer positioned above the user' s feet (but below them) and thus cannot reflect rising radiant heat back into the internal volume of the foot warmer.

[0007] The various embodiments and implementations of the present invention may provide a profusion of potential technical advantages and benefits.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] For a more complete understanding of the present invention and the advantages of certain embodiments, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts, in which:

[0009] Figure 1A is a perspective view of a foot warmer according to one embodiment showing an opening to a volume partially closed in the middle to form two openings so that, when in use, the two openings may surround at least a portion of each of a user's legs, such as the user's ankles or calves, when the user's feet are positioned within the volume of the foot warmer;

[0010] Figure IB is a perspective view of the foot warmer of Figure 1A showing the opening to the volume in a fully open position ;

[0011] Figure 2A is a front elevational view of the foot warmer shown in Figure 1A;

[0012] Figure 2B is a front elevational view of the foot warmer shown in Figure IB;

[0013] Figure 3A is a back elevational view of the foot warmer shown in Figure 1A;

[0014] Figure 3B is a back elevational view of the foot warmer shown in Figure IB;

[0015] Figure 4 is a left side elevational view of the foot warmer shown in Figures 1A and IB;

[0016] Figure 5 is a right side elevational view of the foot warmer shown in Figures 1A and IB;

[0017] Figure 6A is a top view of the foot warmer shown in Figure 1A;

[0018] Figure 6B is a top view of the foot warmer shown in Figure IB; [0019] Figure 7A is a bottom view of the foot warmer shown in Figure 1A;

[0020] Figure 7B is a bottom view of the foot warmer shown in Figure IB;

[0021] Figure 8A is a perspective view of the foot warmer

Figure IB showing a clasp or coupling positioned along the front inside and back inside of the opening to the volume so that the opening may be closed in the middle as illustrated in Figure 1A;

[0022] igure 8B is a perspective view of the foot warmer

Figure IB showing elastic members implemented around the inside of the opening to provide elasticity in the opening so that a user' s feet may be inserted into the foot warmer through the opening and into the internal volume, and the elasticity of the opening may partially enclose around the user' s legs as they are positioned in the opening while the foot warmer is in use to retain more heat within the foot warmer;

[0023] Figure 8C is a perspective view of the foot warmer of Figure IB showing a belt or strap member, which may use a hook and loop fastener, positioned in the front "neck" area below the opening to secure the opening around a user' s legs as they are positioned in the opening while the foot warmer is in use to retain more heat within the foot warmer;

[0024] Figure 8D is a perspective view of the foot warmer of Figure IB, showing a drawstring or cord member, which in certain embodiments may be an elastic cord, with a "cinch" or locking mechanism used to position and hold the drawstring around the area below the opening in a secure manner around a user' s legs as they are positioned in the opening while the foot warmer is in use to retain more heat within the foot warmer;

[0025] Figure 9A is a perspective view of the foot warmer of Figure 1A showing a cutaway portion with the outer fabric removed that would be located above the user' s feet when the foot warmer is in use, and illustrating one embodiment where a radiant barrier layer may be located above the user' s feet and positioned between the outer fabric and the inner fabric, which directly contacts the user's feet when in use;

[0026] Figure 9B is a perspective view of the foot warmer of Figure 1A, and similar to Figure 9A, showing a cutaway portion with the outer fabric removed that would be located above the user's feet when the foot warmer is in use, and illustrating another embodiment where a radiant barrier layer may be located that includes strips or segmented portions of radiant barrier material so that this entire area at this location does not include radiant barrier material;

[0027] Figure 10A is a perspective view of one embodiment of an unassembled foot warmer that includes an inner shell and an outer shell or sack that may be connected using a zipper or other suitable fastener near the opening, and the inner shell includes an inner fabric that contacts the user' s feet when in use, and the outer shell includes both a radiant barrier layer and an outer layer;

[0028] Figure 10B is a perspective view showing the foot warmer of Figure 10A almost fully assembled with the inner shell within the outer shell, and with the zipper/connector of the inner shell and outer shell shown just prior to coupling, and provided near the opening such that the inner material of the inner shell extends up and around the opening to form a rim of the opening that can be seen externally;

[0029] Figure 11 is a perspective view showing the foot warmer of Figure 10A with a cut-away top portion showing three layers that include the outer layer (or fabric) , the radiant barrier layer, and the inner layer (or fabric) exposed below a flap of the radiant barrier layer; and

[0030] Figure 12 is a perspective view that illustrates an embodiment of the foot warmer rolled up that demonstrates the flexibility, ease and transportability of the foot warmer in certain embodiments .

DETAILED DESCRIPTION

[0031] It should be understood at the outset that although an exemplary implementation of the present invention is illustrated below, the present invention may be implemented using any number of techniques, whether currently known or in existence. The present invention should in no way be limited to the exemplary designs, implementations, drawings, and techniques illustrated and described herein. Additionally, the drawings contained herein are not necessarily drawn to scale.

[0032] Before discussing the individual Figures that are included as part of this application, a discussion of the radiant barrier layer is provided. In certain embodiments, a radiant barrier layer may be positioned at least partially surrounding the volume where a user' s feet would reside within the foot warmer, and, in one embodiment, in a position above the volume to reflect radiant heat contained in the volume, which may be at least partially generated by the user's feet, to at least partially reflect such radiant heat back into the volume so that warmth is retained around the feet of the user. In another embodiment, strips or segments of radiant barrier material may be positioned or located around the volume where the user's feet will reside within the foot warmer. An outer fabric layer or outer portions may be provided that substantially surround an inner fabric layer, where the user' s feet resides. In one embodiment, the inner fabric layer or portion is a wool, imitation wool, cotton or other natural or synthetic material/ fabric , such as a polyester fabric, that can be partially seen at certain edges of the foot warmer and/or around the opening in many of the FIGURES that illustrate various embodiments. The term "fabric" as used throughout not only includes cloth, such as weaved or knitted textile fibers, but also all natural, animal, man-made materials, and including plastics, polymers and polyester, or any other material that may be layered. A clasp, coupling, strap, elastic, string or the like may also be provided at, near or adjacent the opening to provide at least some closure of the opening around a user' s legs .

[0033] A radiant barrier layer or material that provides the appropriate reflectivity/emissivity to ensure that adequate radiant heat is retained in the volume is desired. In a preferred embodiment, a radiant barrier that is flexible, does not generate excessive noise when flexed or bent, can be sewn to attach to other fabrics, and is breathable and washable is desired. For example, the radiant barrier integrated with a nonwoven liner material as described in US Patent No. 7,452,833, which is incorporated herein for all purposes, may be used as the radiant layer in one embodiment. This material or layer may be referred to as a metalized heat reflective nonwoven laminate that includes a substantially continuous filament fabric and a film. In one embodiment, the radiant layer/barrier provides a reflectivity in one of the following ranges: at least around 0.95 or greater, at least around 0.90 or greater, at least around 0.85 or greater, at least around 0.80 or greater, at least around 0.75 or greater, or at least around 0.70 or greater. In other embodiments, the reflectivity is at least around 0.30 or greater. The visible metalized surface of the radiant barrier material may be positioned so that such reflective surface is downwardly facing, upwardly facing, or, in implementations where a metal or Mylar layer is provided that is not joined with another layer such that the radiantly reflective material is visible on both upwardly and downwardly facing surfaces.

[0034] Figures 1A - 7B, including all intervening Figures, provide all six views of an embodiment included in this disclosure showing the opening at the top of the volume in both an open and closed state, according to one embodiment, that would more closely surround a user's legs/ankles/calves, depending on the height of a particular implementation of the foot warmer, which may be provided in various heights as desired.. Various aspects of select Figures are discussed further below.

[0035] Figure 1A is a perspective view of a foot warmer 100 according to one embodiment showing an opening 102 to a volume partially closed in the middle to form two openings, 104 and 106, so that, when in use, the two openings 104 and 106 may surround, respectively, at least a portion of each of a user's legs, such as the user's ankles or calves, when the user's feet are positioned within the volume of the foot warmer. As discussed more fully in connection with Figures 8A, 8B, 8C and 8D, other clasps, enclosures, straps and the like may be used to more closely position the opening around a user' s legs when in use so that heat will be retained within the inner volume more readily.

[0036] The opening 102, in one embodiment extends to an open volume, which also may be called an inner volume of the foot warmer 100, that is used to retain a user's feet. An inner fabric 108 is shown through the opening 102, and will preferably be made of a soft fabric, such as a wool, cotton, imitation wool or polyester, that is comfortable to touch. In one embodiment, the entire inner volume is entirely or significantly covered by the inner fabric 108. In a preferred embodiment, the inner fabric extends (or is positioned) around and over the outer portion of the opening 102 to form a cuff or rim around the opening 102. In another embodiment, the inner fabric extends (or is positioned) around or over the various seams, such as the seam 110 that is positioned between a top portion and a bottom portion of the foot warmer.

[0037] An outer fabric 112 is positioned on the outer or exterior portion of the foot warmer 100. This may include any known or desired fabric, and may include various colors and prints, such as zebra, leopard, giraffe, and camouflage patterns and prints, for example. In a preferred embodiment, the outer fabric 112 covers the top/front, bottom, and sides of the foot warmer, but other embodiments may use other fabrics.

[0038] The front/top end 114 will preferably include a curved or desired rounded shape, such as the two rounded ends shown in Figure 1A, that would be positioned near a user' s toes when the foot warmer 100 is in use. The volume where the user' s feet reside is preferably open so that one of the user' s feet may rub or touch the other foot as desired. This provides the capability for a one-size fits all (or most) foot warmer, and provides the capability for a user to rub their feet together if desired without having to remove their feet from the inner volume of the foot warmer 100.

[0039] Figure IB is a perspective view of the foot warmer 100 of Figure 1A showing the opening 102 to the inner volume in a fully open position with the center clasp not engaged, as it is in Figure 1A. The inner fabric 108 is shown along the cuff or rim of the opening 102. A left side panel 116 is shown covered with the outer fabric 112, while a back seam 118 is provided using the inner fabric 108.

[0040] In a preferred embodiment, the inner fabric 108 is made of a soft, napped polyester fabric that may be considered imitation wool that is pleasing to the touch. As discussed, a portion of the inner fabric 108 is shown lining the various edges or seams as the inner fabric intersects with the outer fabric 112, in one embodiment. In certain in embodiments, the inner fabric 108 may be externally attached or sew at these seams .

[0041] What is not visible in Figures 1A and IB is the radiant barrier layer, which in a preferred embodiment is sewn between the inner fabric or layer 108 and the outer fabric layer 112 above where the user' s feet will reside within the inner volume formed by the foot warmer. This radiant barrier, in other embodiments, may be positioned entirely around the volume or at select locations or in strips so that radiant heat is reflected back into the volume to ensure a warm, cozy and comfortable environment within the volume for the user's feet. Assuming the embodiment with the radiant barrier layer positioned only over where the user' s feet will reside in the volume of the foot warmer 100, if the user's feet become too warm because of the heat retaining effects of the radiant barrier, the user may turn the foot warmer 100 over so that the inner top portion of the inner volume now is the inner bottom portion of the inner volume such that the radiant barrier layer now resides or is positioned below the user's feet, thus allowing rising radiant heat to escape and, hence, allowing the user's feet to cool to a comfortable temperature.

[0042] Figure 2A is a front elevational view of the foot warmer 100 of Figure 1A, while Figure 2B is a front elevational view of the foot warmer 100 of Figure IB. Similarly, Figure 3A is a back elevational view of the foot warmer 100 of Figure 1A, while Figure 3B is a back elevational view of the foot warmer 100 of Figure IB. The front and back of the foot warmer 100 in other embodiments may include decorative elements, and or designs. For example, in one embodiment, the front portion of the foot warmer 100 shown in Figure 2A may include a logo or slogan, and in other embodiments may includes a stuffed animal or character that may be attached permanently, such as by an adhesive or sewing, or using a hook and loop fastener. Such a stuffed animal or character may be provided at location 120 or location 122 as shown in Figure 2A.

[0043] Figure 4 is a left side elevational view of the foot warmer 100 of Figures 1A and IB, and Figure 5 is a right side elevational view of the foot warmer 100 of Figures 1A and IB. The side panel, such as the left side panel 116 or a right side panel 126, may be sewn or manufactured separately as one unit in one embodiment, and will, in a preferred embodiment, include the outer fabric 112. In one embodiment, a stuffing 130 may be provided in the top/front portion between the outer fabric 112 and the inner fabric 108. Thus, stuffing 130 is not externally visible because it is positioned between the outer fabric 112 and the inner fabric 108. The radiant barrier layer may be above or below the stuffing 130, as desired, and will also be positioned between the outer fabric 112 and the inner fabric 108. The stuffing 130 may be a batten or cushioning type material to provide more comfort and/or rigidity to the structure of the foot warmer 100 if desired.

[0044] Figure 6A is a top view of the foot warmer 100 according to one embodiment, and Figure 6B is a top view of the foot warmer 100 of Figure IB. The rounded front/top end 114, although not required, may include shapes of virtually any desired shape.

[0045] Figure 7A is a bottom view of the foot warmer 100 of Figure 1A, and Figure 7B is a bottom view of the foot warmer 100 of Figure IB. In one embodiment, the outer fabric 112 is also provided along the bottom as shown, and in other embodiments the material on the bottom of the foot warmer 100 may include anti-skid or anti-slip material. Although in use, a user of the foot warmer 100 will be in a chair, couch, bed and the like, and will not walk while using the foot warmer 100, in the event a user places the bottom of the foot warmer 100 on a slick surface and does not want the bottom of the foot warmer 100 to slide on the slick surface, the non-skid surface may provide this feature.

[0046] As mentioned above, Figures 8A, 8B, 8C and 8D each provide examples of other mechanisms and implementations to ensure the opening 102 is positioned closely, and possibly snuggly, next to the user's legs after the user's feet are inserted into the opening 102, which needs to initially be opened widely to allow for the convenient insertion of the user's feet into the inner volume of the foot warmer 100. Figure 8A is a perspective view of the foot warmer 100 of Figure IB showing the clasp or coupling 140 positioned along the front inside and coupling 142 positioned along the back inside of the opening 102 to the volume so that the opening 102 may be closed in the middle as illustrated in Figure 1A. Figure 8B is a perspective view of the foot warmer 100 of Figure IB showing elastic members 144 implemented around the inside of the opening 102 to provide elasticity in the opening 102 so that a user's feet may be inserted into the foot warmer through the opening 102 and into the internal volume, and the elastic members 144 of the opening 102 may partially enclose around the user' s legs as they are positioned in the opening 102 while the foot warmer 100 is in use to retain more heat within the volume of the foot warmer 100.

[0047] Figure 8C is a perspective view of the foot warmer 100 of Figure IB showing a belt or strap member 146, which may use a hook and loop fastener, positioned in the front "neck" area below the opening 102 to secure the opening 102 around both legs of a user as they are positioned in the opening 102 while the foot warmer 100 is in use. This may include a loop to tighten the belt or strap member 146, or, in other embodiments, include a hook and loop fastener. Figure 8D is a perspective view of the foot warmer 100 of Figure IB, showing a drawstring or cord member 150, which in certain embodiments may be an elastic cord 150, with a "cinch" or locking mechanism 148 used to position and hold the drawstring around the area below the opening 102 in a secure manner around a user's legs as they are positioned in the opening 102 while the foot warmer 100 is in use to retain more heat within the foot warmer 100.

[0048] Figure 9A is a perspective view of the foot warmer 100 of Figure 1A showing a cutaway portion with the outer fabric 112 removed that would be located above the user's feet when the foot warmer 100 is in use, and illustrating one embodiment where a radiant barrier layer 200 may be located above the user' s feet and positioned between the outer fabric 112 and the inner fabric 108, which directly contacts the user's feet when in use. In an alternative embodiment, the radiant barrier layer 200 may be provided entirely or partially around the volume of the foot warmer 100, and below the outer fabric 112. In other embodiments, such as that shown in Figure 9B and which is a perspective view of the foot warmer 100 similar to Figure 9A, a radiant barrier strips or segments 202 may be used as desired. This allows for the tempering of the radiant heat retention function of the radiant barrier layer so that some of the radiant heat may escape in areas where the radiant barrier strips 202 are not present. The cutaway portion of Figure 9B shows the outer fabric 112 removed at a location above where the user' s feet would be located when the foot warmer 100 is in use, and illustrates various radiant barrier strips 202 that may be may be located that includes strips or segmented portions of radiant barrier material so that this entire area at this location does not include radiant barrier material .

[0049] Figure 10A is a perspective view of one embodiment of an unassembled foot warmer that includes an inner shell 502 and an outer shell or sack 504 that may be connected using a zipper or other suitable fastener, such as zippers 520 and 522, near the opening, and the inner shell 502 includes an inner fabric 514 that contacts the user' s feet when in use, and the outer shell 504 includes both a radiant barrier layer 510 and an outer layer 512.

[0050] Figure 10B is a perspective view showing a foot warmer 500 of Figure 10A almost fully assembled with the inner shell 502 positioned within the outer shell 504, and with the zipper/connector 520 of the inner shell 502 and the zipper 522 of the outer shell 504 shown just prior to coupling, and provided near the opening such that the inner material 514 of the inner shell 502 extends up and around the opening to form a rim of the opening that can be seen externally. This provides an example of the radiant barrier layer 510 extending around the volume where the user's feet will reside. In other embodiments, the outer shell 504 does not extend the radiant barrier layer 510 entirely around the shell.

[0051] Figure 11 is a perspective view showing the foot warmer 100 of Figure 10A with a cut-away top portion 600 showing three layers that include the outer layer (or fabric) 112, the radiant barrier layer 200, and the inner layer (or fabric) 108 exposed below a flap of the radiant barrier layer 200. In this embodiment, the radiant barrier layer 200 is sandwiched directly between the outer fabric 112 and the inner fabric 108, which makes up the inner volume that contacts the user's feet. In a preferred embodiment, the volume of the foot warmer 100 is such that, when not in use, a portion of the top of the inner volume resides on a portion of the bottom of the inner volume. In this way, when a user's feet are inserted, the top and bottom portion of the inner volume, which preferably is made of the comfortable inner fabric 108, contacts both the top and bottom of the user' s feet to provide more warmth and comfort.

[0052] In an alternative embodiment, a heat retaining member may be included in or adjacent the volume of the foot warmer 100, such as between the outer fabric 112 and the inner fabric 108. The heat retaining member may include rice, husks, or some natural material that may be heated in a microwave to generate heat in the heat retaining member, so that heat, in addition to the user's feet, is retained in the foot warmer 100. In such a case, all metallic couplings and/or items that cannot be microwaved would need to be implemented using other materials that are microwave safe.

[0053] Figure 12 is a perspective view that illustrates an embodiment of the foot warmer 100 rolled up that demonstrates the flexibility, ease and transportability of the foot warmer in certain embodiments. Hand 700 is shown holding the rolled up foot warmer 100. The foot warmer 100 can be taken virtually anywhere and used while sitting or reclined, even at the office .

[0054] It should be understood that the height of the "neck" portion below the opening may be longer or shorter as desired, and this invention is not limited to a particular height. In a preferred embodiment the radiant barrier is quiet when flexed, and is flexible, washable, and breathable material that will reflect radiant heat back into the inner soft shell, such as when a user' s feet are generating radiant heat within the soft inner shell.

[0055] Thus, it is apparent that there has been provided, in accordance with the present invention, an apparatus and method for warming extremities that may include a foot warmer for warming feet that provides one or more of the advantages set forth above. Although the preferred embodiment has been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the scope of the present invention, even if all of the advantages and benefits identified above are not present. For example, the various embodiments and examples shown in the drawings and descriptions provided herein illustrate that the present invention may be implemented and embodied in numerous different ways that still fall within the scope of the present invention, whether expressly shown herein or not. For example, the various elements or components may be combined or integrated in another system or certain features may not be implemented. Also, the techniques, systems, sub-systems, and methods described and illustrated in the preferred embodiment as discrete or separate may be combined or integrated with other systems, designs, techniques, or methods without departing from the scope of the present invention. Other examples of changes, substitutions, and alterations are readily ascertainable by one skilled in the art and could be made without departing from the spirit and scope of the present invention .