Abstract:
An emergency anti-hypothermia system has a thermally insulating vest that is sufficiently portable to be carried for emergency use in a pocket, purse, backpack, compartment of a vehicle, ski pole or other location, with the vest providing thermal insulation by being made with thermally insulating air impervious material that also provides for its inflation. A multiplicity of interconnected inflated chambers situated about the vest, provides thermal insulation by anti-conduction, anti-radiation and anti-convection in a highly portable system. An outer surface having radar reflective properties further improves visibility of the vest.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Every winter, drivers are stranded on roads, run the engines of their vehicles until they run out of gas or other vehicle fuel, and then are subjected to hypothermia while they wait for assistance at a location to which they have not brought sufficiently insulating clothing. Skiers or others participating in winter outdoor activities may similarly dress for a planned short time outside, but then fall or otherwise become caught by unexpected conditions that lead to exposure to cold sufficient to produce hypothermia. Still others may find themselves in such conditions with insufficient clothing insulation. Hypothermia is a danger to victims of natural disasters, and even to persons simply changing a tire on a roadside in winter night. 
         [0002]    Hypothermia is defined as the unintentional lowering of the deep body (core) temperature below 95.0° F. (35.0° C.). Hypothermia can be mild, moderate, or severe. According to the CDC, 10,649 deaths were attributed to weather-related causes in the United States during the period from 2006 through 2010. Two-thirds of these deaths were attributed to excessive natural cold. (See: Deaths Attributed to Heat, Cold, and Other Weather Events in the United States, 2006-2010; http://www.cdc.gov/nchs/data/nhsr/nhsr076.pdf). 
         [0003]    Since 1999, the CDC&#39;s National Center for Health Statistics (NCHS) has used information from death certificates categorized with International Classification of Diseases codes to estimate national mortality trends. During 1999, exposure to excessive natural cold (ICD-10 code X31) was listed as the underlying cause of death for 598 persons in the United States, and hypothermia (ICD-10 code T68) was listed as a nature of injury in 1,139 deaths. Of the 598 hypothermia-related deaths, 380 (64%) occurred among males, and 359 (60%) of the 597 persons who died of hypothermia and whose age was known were aged &gt;65 years. During 1999, Pennsylvania and New York had the greatest number of hypothermia-related deaths (36 each), and Alaska had the highest death rate (1.9 per 100,000 population), approximately twice that of Montana, which had second-highest rate (0.9). 
         [0004]    Hypothermia during cold weather is the result of decreased heat production, increased heat loss, or impaired thermoregulation. Older persons, who have a decreased basal metabolic rate, might be at further risk for hypothermia because of impaired physical exertion, which produces heat to keep the body warm. Inactivity limits heat production through physical exertion, but overexertion can increase evaporation from the respiratory tract and cause fatigue. Shivering also can cause enough lactate generation eventually to produce acidosis and fatigue. Exposure to high winds can further increase heat loss. As body temperature decreases, the hypothalamus fails to compensate body temperature, and the central nervous system follows the progressive systemic depression of metabolism. Finally, metabolic impairment from alcoholism, malnutrition, hypothyroidism, or advanced age can cause poor endurance to cold. Children, who have a much greater surface—are to metabolic mass, are at even greater risk from hypothermia. 
         [0005]    Hypothermia-related morbidity is not exclusive to cold northern climates. Hypothermia can occur in cold and warm climates alike. In fact, a survey of 12 medical centers found that the greatest number of cases of accidental hypothermia occurred in warmer states. Hypothermia has been reported in tropical countries as well. Persons from regions with warmer winters might be at greater risk from the indirect effects of cold weather than persons from regions with colder and longer winters because of inexperience in dealing with cold temperatures. However, geographic distributions might represent not only seasonal temperature variations but also socioeconomic status (which can limit access to controlled indoor temperature), cultural backgrounds (which can influence behavior toward individual protection from cold as well as outdoor activity), or populations with a higher proportion of elderly persons. 
         [0006]    The foregoing indicates that an emergency anti-hypothermia system for such conditions is needed. The present invention provides such a system. It provides a thermally insulating inflatable vest that is sufficiently portable to be carried for emergency use in a pocket, purse, backpack, or other such location on a person, or also in a compartment of a vehicle. 
         [0007]    The vest provides thermal insulation by being made with air impervious material that also provides for its inflation. The inflating air also provides insulation. Thermal radiation reflective material on inwardly facing surfaces of the vest, preferably inwardly facing surfaces of outer layers of inflated chambers or cells about the vest, serves to retain body heat. The multiplicity of individual inflatable chambers about the vest reduces convection heat transfer. The vest thus preferably provides thermal insulation by anti-conduction, anti-radiation and anti-convection in a highly portable system. 
         [0008]    Various other features and attendant advantages of the present invention will become obvious to the reader and become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings. It is intended that these objects and advantages are within the scope of the present invention. To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings. Attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of this application. 
       SUMMARY OF THE INVENTION 
       [0009]    A highly portable, inflatable emergency vest is provided. The vest contains cells, or chambers, which are cross-connected and inflated trough a simple one-way mouthpiece on the vest&#39;s collar. Inflating the vest creates a layer of trapped, still air in much the same way as does goose down, while conforming to the shape of the wearer, thus insulating the wearer&#39;s body core while allowing moist air to escape through the arm holes and through the integrated vent holes. The interior surface of the vest is thermally reflective, thereby keeping body heat trapped next to the user and preventing as much as 80% to 90% of radiant heat loss. The exterior surface of the vest further is made of radar reflective material. This greatly increases the radar visibility of the vest, to aid in search and rescue efforts to locate a wearer who has become lost or incapacitated. This feature is also useful by operators of small boats and kayaks as it permits positive radar indication of the wearer&#39;s location on the surface of large bodies of water from long distances. 
         [0010]    The manufacturing process involves placing a first sheet of material onto a second sheet and then bonding the two sheets together along the edges and interiorly by either thermally or ultrasonically welding the first sheet to the second sheet to form the interconnected chambers. The sheets may be preprinted in any preferred color(s) and with any sort of decorative elements desired, through offset printing or other known means. Adhesive strips are attached to the vest for closures. Once assembled, the uninflated vest may be stored in small container or pouch for easy portability. For safety/high-visibility applications, reflective ink for textiles may be used. Such inks are composed of a water-based (latex) ink base combined with retro-reflective microlenses. This process is used for direct screen printing onto fabric or plastics, and the end result with respect to visibility is the same. Retro-reflective films may also be used, being applied to the outside sheet before or after the bonding process. 
         [0011]    Other features and advantages of the present invention are described below. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0012]    Preferred embodiments will now be described with respect to the following drawings that illustrate but do not limit the invention. 
           [0013]      FIG. 1  is a depiction of one embodiment of the vest of the present invention. 
           [0014]      FIG. 2  is a depiction of the embodiment of the vest shown in  FIG. 1  as it is intended to be worn, with the vest inflated with air. 
           [0015]      FIG. 3  is a depiction of the vest of the present invention laid out as a flattened single piece. 
           [0016]      FIG. 4  is a depiction of the vest of the present invention laid out as pair of flattened pieces, to be combined into a single vest during the manufacturing process. 
           [0017]      FIG. 5  is a depiction of an embodiment of the present invention in which the vest further comprises non-inflatable sleeves. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0018]    The present invention discloses an emergency anti-hypothermia system. In one embodiment, the system comprises an inflatable vest  100 . See  FIG. 1 . The vest  100  is made with air impervious material such that air introduced to the interior of the vest  100  is contained therein, thus inflating at least a portion of the vest  100 . Preferably, the vest  100  is made from a high tensile-strength polyester film, such as aluminized nylon sheet, coated on one side with polyethylene and metalized on the other). The material is electrically resistant, chemically stable, noncombustible (94VTM-2), and comes in thicknesses ranging from 0.001 inches to 0.014 inches. It is a thermoplastic polymer, and is thermally and ultrasonically fusible. It may come in colors from matte to metalized. 
         [0019]    The vest  100  is structured with a closeable front  110 , substantially full sides  122 , 124  of the vest  100 , and a substantially full back  130  extending from the neck area  136  to the waist area  138  of the vest  100 . The vest  100  moreover has an outer surface and an inner surface, with there being thermal radiation reflective material on at least a portion of the inner surface of the vest  100 . When inflated, the vest  100  is thermally insulating around the front  110 , sides  122 , 124 , and back  130 . 
         [0020]    In one embodiment the vest  100  is manufactured as a single part. See  FIG. 3 . In another embodiment the vest  100  is manufactured in two parts, a left side and a right side. See  FIG. 4 . The two part manufacturing method requires the left and right sides to be joined together during final assembly. This can be done by a lateral portion of the material of each of the sides being fused together. Alternatively, these portions can be secured together by tape  202  attached to one of the sides engaging with the other side. An advantage of the two part manufacturing process is that the left and right sides are independently inflatable, so a catastrophic loss of integrity on one side will not cause a loss of insulation on the other side. 
         [0021]    The part of the vest  100  that is inflatable comprises a plurality of interconnected chambers  180 . See  FIG. 1 . The chambers  180  are located on the upper and lower portions of at least the front  110  of the vest  100  and cross-connected. Preferably, the chambers  180  are located on the upper and lower portions of the front  110 , back  130 , and sides  122 , 124  of the vest  100 . The inner surface of the vest  100  is on the outside of the chambers  180 , and the outer surface of the vest  100  is on the outside of the chambers  180 . Each chamber  180  is formed by partially fusing portions of the inner surface and the outer surface of the vest  100  to each other, with the fused portions forming an incomplete perimeter of the chamber  180 . The portion of the perimeter not fused communicates with an adjoining chamber  180 . Thus, each chamber  180  is in communication with at least one other chamber  180 , and at least one chamber  180  is in communication with the inflation tube  160 . For vests  100  constructed of two sets of interconnected chambers  180  (see  FIG. 4 ), one inflation tube  160  is required for each. 
         [0022]    The inflation tube(s)  160  comprise a simple one-way mouthpiece, for example a flap valve made of the film material of the vest  100  on the vest&#39;s collar  170 . See  FIG. 3 . Other configurations of the inflation tube  160  are also contemplated, including an injection molded mouthpiece with an integrated one-way valve. Air introduced into the vest  100  through the inflation tube  160  enters the at least one chamber  180  communicating with it, and passes from that chamber  180  into each other chamber  180  via the communications therebetween until every chamber  180  within the vest  100  contains air. The inflation tube&#39;s  160  one-way valve prevents air from escaping the vest  100  during use. The valve may be manipulated, however, to allow air to escape the vest  100 , thereby deflating the vest  100  for subsequent use. 
         [0023]    One or more of the chambers  180  may have an inter-chamber fusion  182  joining the inner surface of the vest  100  to the outer surface of the vest  100 . See  FIG. 1 . Such chambers  180  thus appear substantially toroid, rather than spherical. The inter-chamber fusions  182  provide structural rigidity to the vest  100 , allowing it to retain its desired shape when inflated, thus minimizing the loss of heated air between the wearer and the vest  100  through gapping of the vest  100 . 
         [0024]    The vest  100  may be provided in a deflated state, flattened out as a single sheet. See  FIG. 3 . This allows for compact folding for storage purposes. In one embodiment, in order to use the vest  100 , the shoulders  126 , 128  need to be formed and the front  110  needs to be closed. The user thus joins the upper portion  114  of one side of the front  110  of the vest  100  to the upper portion  134  of the corresponding side of the back  130  of the vest  100  to form one shoulder  126 , and joins the upper portion  118  of the other side of the front  110  of the vest  100  to the upper portion  134  of the corresponding side of the back  130  of the vest  100  to form the other shoulder  128 . In the preferred embodiments each shoulder  126 , 128  is formed by a tape  202  attached to the upper portion  114  of the front  110  of the vest  100  engaging with the corresponding upper portion  134  of the back  130  of the vest  100 . Alternatively, the tape  202  may be attached to the upper portion  134  of the back  130  of the vest  100 , and engages with the corresponding upper portion  114  of the front  110  of the vest  100 . In either configuration, the tape  202  may further comprise a protective covering on its outside surface, to prevent adhesion prior to use. In other embodiments the shoulders  126 , 128  are pre-taped or fused during the manufacturing process, and no further action need be taken by the user with regard to the shoulders  126 , 128  prior to wearing the vest  100 . 
         [0025]    The user dons the vest  100  by inserting each arm through a corresponding armhole formed by the side  122 , back  130 , front  110 , and shoulder  126  of the vest  100 . Then the front  110  of the vest  100  is closed by bringing one side  112  of the front  110  of the vest  100  into contact with the other side  116  of the front  110  of the vest  100 . See  FIG. 2 . In the preferred embodiments the first side  112  of the front  110  of the vest  100  engages with the second side  116  of the front  110  of the vest  100  by a tape  202 , hook and loop fastener (Velcro®), or other adhesive means, which is attached to the first side  112  of the front  110  of the vest  100 . It does not matter which side (left or right) has the fastening means attached. If used, the tape  202  may further comprise a protective covering on its outside surface, to prevent adhesion prior to use. 
         [0026]    In a preferred embodiment, the vest  100  comprises a radar reflective material on at least a portion of its outer surface. This may be aluminized nylon or other high tensile-strength polyester film metalized on one or both surfaces. The radar reflecting properties of materials such as these are well-established. When inflated, this flexible metalized material forms three-dimensional radar reflective surfaces, presenting much greater reflective opportunity to incident radar waves, and thus aiding in search and rescue operations. In another preferred embodiment, the vest  100  comprises integrated vent holes  150  located in the front  110 , sides  122 , 124 , and back  130 . These vent holes  150  are punched through the welded vest  100  material at chamber  180  intersections points during the manufacturing process, and allow for greater transfer of moisture from perspiration to the outside of the garment, thereby enhancing wearer comfort and the vest&#39;s  100  insulating properties. In yet another preferred embodiment, the vest  100  comprises an integrated inflation tube  160 . This tube  160 , positioned on the front collar  170 , greatly improves the process of vest  100  inflation. In yet another preferred embodiment, the vest  100  comprises a non-inflating integrated collar  170 . This collar  170  is produced by fusing both layers of the vest  100  material, thus creating a wind barrier and additional heat reflective surface at the back of the wearer&#39;s neck, aiding in overall comfort and utility. In the most preferred embodiment each of these features is incorporated into the vest  100 . 
         [0027]    In one variant, the vest  100  has a pair of non-inflatable sleeves  190 . See  FIG. 5 . The sleeves  190  are constructed of a single ply of inwardly aluminized material, with vent holes  150  and tape  202  wrist closures. This configuration provides additional insulation to the extremities, while allowing the overall bulk of the vest  100  to remain as small as possible. 
         [0028]    What has been described and illustrated herein is a preferred embodiment of the invention along with some it its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention in which all terms are meant in their broadest, reasonable sense unless otherwise indicated. Any headings utilized within the description are for convenience only and have no legal or limiting effect.