Patent Publication Number: US-2018035491-A1

Title: Composition energy unit

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to the textile industry and, more particularly, to materials that are specifically designed to produce and/or retain thermal energy. 
     BACKGROUND OF THE INVENTION 
     Prolonged exposure to cold temperatures in cold-weather environments can cause certain medical hazards. For instance, hypothermia is a dangerous medical condition which occurs when the human body dissipates heat at a rate that results in a significant drop in body temperature. 
     To prepare against such hazards, cold-weather clothing is commonly worn. As can be appreciated, cold-weather, or winter, apparel minimizes the dissipation of body heat and thereby ensures that the body temperature of an individual is maintained at a healthy level. 
     Certain materials are commonly utilized to maximize effectiveness in maintaining a suitable body temperature. Traditionally, thermal garments rely on relatively thick materials, such as fur, down feathers, cotton and other insulated fabrics, which are in turn often arranged in multiple layers, to create adequate warmth to the wearer. However, this design renders conventional cold-weather apparel rather bulky and heavy in nature. Due to its relative inflexibility and overall lack of comfort, cold-weather clothing is typically considered both unfashionable and unpleasant to wear. 
     In the textile industry, the use of nanofiber technology has gained recent prominence in the design of effective thermal protective clothing. By using polymer-based nanofibers applied with high thermal conductivity coatings, thinner and lighter articles of clothing have been manufactured that assist in the retention of body heat. 
     Although there have been advancements, winter apparel still remains relatively heavy, thick and inflexible. Furthermore, it has been found that winter apparel is still often incapable of maintaining an adequate body temperature for an extended period of time, particularly in extreme cold environments, such as a polar region. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a new and improved unit, or article, for retaining thermal energy in cold-weather environments. 
     It is another object of the present invention to provide a thermal energy article as described above that is designed to maintain the body temperature of an individual within a suitable range for an extended period of time, even in extreme cold conditions. 
     It is yet another object of the present invention to provide a thermal energy article as described above that is thin, light and comfortable to wear. 
     It is still another object of the present invention to provide a thermal energy article as described above that has a limited number of parts and is relatively inexpensive to manufacture. 
     Accordingly, as one feature of the present invention, there is provided a composition energy unit, comprising (a) a light-heating fabric adapted to absorb and release infrared thermal energy, the light-heating fabric being a metal-based fabric, and (b) an electric-heating system disposed at least partially within the light-heating fabric, the electric-heating system being electrically powered to produce infrared thermal energy, (c) wherein the light-heating fabric and electric-heating system operate independently of one another. 
     Various other features and advantages will appear from the description to follow. In the description, reference is made to the accompanying drawings which form a part thereof, and in which is shown by way of illustration, an embodiment for practicing the invention. The embodiment will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. The following detailed description is therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings wherein like reference numerals represent like parts: 
         FIG. 1  is a top view of a composition energy unit constructed according to the teachings of the present invention; and 
         FIG. 2  is an enlarged, fragmentary, section view of the composition energy unit shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Composition Energy Unit  11   
     Referring now to  FIGS. 1 and 2 , there is a shown a composition energy unit which is constructed according to the teachings of the present invention, the composition energy unit being identified generally by reference numeral  11 . As will be described further below, composition energy unit  11  is designed to generate heat using two separate and largely independent sources. In this manner, composition unit  11  is particularly well suited to maintain the body temperature of an individual at an acceptable level in cold-weather environments for an extended period of time. 
     For simplicity purposes only, composition energy unit  11  is represented herein as a generally rectangular swatch. However, in the preferred application of the present invention, composition energy unit  11  is preferably configured as an article of clothing, such as a jacket. In this manner, a person can be most effectively warmed by simply wearing the article. 
     Nonetheless, it should be noted that unit  11  is not limited to any particular size, shape or configuration. Rather, it is to be understood that composition energy unit  11  could be constructed in a wide variety of different forms which are suitable for providing warmth to an individual, such as in the shape of a unitary blanket, sheet, automotive seat or the like, without departing from the spirit of the present invention. 
     As referenced briefly above, composition, or thermal, energy unit  11  utilizes two separate and largely independent means of producing thermal energy, namely, (i) a light-heating fabric  13  that substantially surrounds, or envelops, (ii) an electric-heating system  15 . Through the use of dual, independent and redundant thermal energy sources, unit  11  is highly effective in maintaining the body temperature of an individual within a target temperature range for an extended period of time, even in extreme cold conditions. Furthermore, composition energy unit  11  achieves the aforementioned thermal requirements while maintaining a thin, light and flexible construction, which is a principal object of the present invention. 
     Light-Heating Fabric  13   
     Light-heating fabric  13  is preferably a metal-based, needle-punched, nonwoven fabric that both absorbs and releases safe infrared thermal energy within its immediate environment. By drawing thermal energy from other resources (e.g., the sun or electric-heating system  15 ), fabric  13  is able to provide enough heat to maintain the body temperature of an individual within a safe range for an extended period of time, which is highly desirable. 
     For ease in manufacturing unit  11 , light-heating fabric  13  is represented herein as comprising a first fabric layer  17 - 1  and a second fabric layer  17 - 2  that are secured together along their respective peripheries and in a designated pattern within its interior region using a thread-based stitching  19 . As will be explained further below, stitching  19  serves to retain electric-heating element  15  fixedly in place between layers  17 - 1  and  17 - 2 . 
     It should be noted that, in lieu of stitching  19 , alternative means for securing layers  17 - 1  and  17 - 2  together could be realized without departing from the spirit of the present invention. For instance, layers  17 - 1  and  17 - 2  could be selectively bonded together using an appropriate adhesive. 
     Fabric  13  is preferably formed using light-heating nanofibers, the construction of which is novel and, as such, serves as a principal feature of the present invention. Each nanofiber in fabric  13  effectively absorbs infrared thermal energy from its immediate environment which, in turn, causes the nanofiber itself to warm to the extent so as to generate considerable heat. 
     Notably, within one minute of exposure to the sun in a temperature environment of approximately 1° C. (33.8° F.) to approximately 3° C. (37.4° F.), each nanofiber experiences a commensurate rise in temperature in the range from approximately 25° C. (77° F.) to approximately 40° C. (104° F.), which is approximately three times greater than the temperature rise of conventional fibers. Because the wavelength of the infrared thermal energy released by fabric  13  is similar to the wavelength of thermal energy released by the human body, fabric  13  is safe to wear. Furthermore, the construction of each nanofiber renders fabric  13  in compliance with both the Standard 100 by OEKO-TEX® and the REACH 2016 textile certification standards. 
     Each light-heating nanofiber is constructed from a mixture comprising (a) metal complex pellets and (b) polymer pellets, each type of pellet having a preferred range in diameter from approximately 1.5 nm to approximately 2.0 nm. The mixture of pellets is, in turn, electrospun together through a process that includes the steps of drying, melting, spinning, steaming, fixing, cutting and packing. It should be noted that the metal complex pellets and the polymer pellets may constitute the entirety of the nanofiber mixture or, in the alternative, the nanofiber mixture may include certain additional materials not referenced herein. 
     The resultant light-heating nanofiber created through the electrospinning process referenced above preferably has a denier in the range of approximately 1.5 d to approximately 20.0 d and a length in the range of approximately 25 mm to approximately 200 mm. However, it is to be understood that the specifications associated with each nanofiber could be modified without departing from the spirit of the present invention. 
     The specific composition of each metal complex pellet is provided in further detail below. Each polymer pellet is preferably formed of a material from the group consisting of polyester, nylon, acrylic, polypropylene, viscose, or a combination thereof. Most preferably, each polymer pellet is in the form of a semi-dull polyester pellet. 
     In the preferred mixture for each nanofiber, the metal complex pellets preferably constitute approximately 5% to 20% of the mixture. More narrowly, the metal complex pellets preferably constitute approximately 7% to 18% of the mixture. However, through extensive testing, it has been determined that optimum results are achieved when the metal complex pellets constitute 10% to 15% of the mixture. 
     Correspondingly, in view of the above, the polymer pellets preferably constitute approximately 80% to 95% of the mixture used to create each nanofiber. More narrowly, the polymer pellets preferably constitute approximately 82% to 93% of the mixture. However, through extensive testing, it has been determined that optimum results are achieved when the polymer pellets constitute 85% to 90% of the mixture. 
     The metal complex used in the mixture to form each nanofiber preferably includes a metal and a dispersant. It should be noted that the metal and the dispersant may constitute the entirety of the metal complex or, in the alternative, the metal complex may include certain additional materials not referenced herein. 
     The metal used to form the pellets of the metal complex is preferably cesium tungsten complex or zirconium complex. This metallic material used to form the metal pellets is preferably provided in powdered form with a diameter in the range of approximately 10 nm to approximately 30 nm, more narrowly, with a diameter in the range of approximately 15 nm to approximately 25 nm, and even more narrowly, with a diameter in the range of approximately 18 nm to approximately 23 nm. 
     In the mixture used to form the metal complex, the metal (e.g., cesium tungsten complex or zirconium complex) preferably constitutes approximately 40% to 80% of the mixture and the dispersant preferably constitutes at least the majority of the remaining 20% to 60% of the mixture. Most preferably, in the mixture for the metal complex, the metal constitutes approximately 60% of the mixture and the dispersant constitutes approximately 40% of the mixture. 
     Electric-Heating System  15   
     As referenced briefly above, electric-heating system  15  provides an independent, redundant heating source to thermal energy unit  11 . In other words, when light-heating fabric  13  is incapable of producing adequate thermal energy (e.g., in an environment with limited infrared energy to be absorbed and subsequently released), electric-heating system  15  provides the necessary thermal energy to maintain the body temperature of an individual within a desired temperature range. 
     Electric-heating system  15  comprises at least one heating element  21  that is disposed within fabric  13  (i.e. between layers  17 - 1  and  17 - 2 ). Heating element  21  is in the form of any thermally conductive element that converts electricity into heat through a process of resistive heating. For instance, heating element  21  may be in the form of an elongated, continuous, metallic resistance wire. 
     In the present embodiment, heating element  21  is arranged in thermally optimal configuration between layers  17  (e.g. as a planar ribbon or coil spread evenly to create uniform energy dispersion). A first end of element  21  terminates between layers  17 , whereas a second end of element  21  preferably extends to the periphery of fabric  13  so as to be externally accessible. As seen most clearly in  FIG. 1 , stitching  19  is preferably applied immediately surrounding conductive element  21 . In this manner, heating element  21  is retained in a fixed relationship relative to fabric  13 . 
     Conductive element  21  is adapted for electrical connection to a power source. For instance, as represented herein, the second end of heating element  21  is electrically connected to a USB-type connector  23 . In turn, connector  23  is adapted for direct electrical coupling to a designated external power source, such as a battery (not shown). 
     For instance, electric-heating system  15  is designed to be powered by a 3-9 volt (preferably 5 volt) lithium battery with a current of approximately 1-2 amperes, thereby rendering system  15  compliant with both IEC 227 and IEC 228 certification standards. However, electric-heating system  15  could be powered by alternative electrical sources without departing from the spirit of the present invention. 
     For ease of recharging and/or replacement, the battery is preferably located outside of fabric  13 . However, it is to be understood that the entirety of electric-heating system  15 , including the electrical power source, could be located entirely within fabric  13  without departing from the spirit of the present invention. 
     Measured Test Results Achieved Using Unit  11   
     A pair of actual composition energy units  11  was constructed in accordance with the teachings set forth in detail above. In turn, each unit  11  was tested in specific cold-weather conditions to measure its effectiveness in producing thermal energy. The results of such testing are provided herein. However, it is to be understood that the results are being provided for illustrative purposes only and are not to be construed in a limiting fashion. 
     In connection with a first testing process, a first embodiment of a composition energy unit  11  was constructed in which light-heating fabric  13  was formed using nanofibers constructed from a mixture consisting of 5% metal complex pellets and 95% polymer pellets. The fabric  13  was shaped into a generally rectangular swatch having a length of approximately 25 cm and a width of approximately 15 cm. 
     With a 5 v battery connected to electric-heating system  15 , the first embodiment of composition energy unit  11  was able to operate for over 5 hours producing the necessary heat to maintain an individual within a desired temperature range. Through the use of the dual heating sources (i.e. light-heating and electrical-heating sources), the first embodiment of composition energy unit  11  was able to effectively create, within two minutes, an immediate thermal environment with a temperature of approximately 30° C. (86° F.). Upon withdrawal of the electric-heating source (i.e. the battery), the unit  11  returned to the ambient temperature after approximately 9 minutes, which is approximately three times longer than conventional materials. 
     In connection with a second testing process, a second embodiment of a composition energy unit  11  was constructed in which light-heating fabric  13  was formed using nanofibers constructed from a mixture consisting of 10% metal complex pellets and 90% polymer pellets. The fabric  13  was shaped into a generally rectangular swatch having a length of approximately 25 cm and a width of approximately 15 cm. 
     With a 5 v battery connected to electric-heating system  15 , the second embodiment of composition energy unit  11  was able to effectively create, within two minutes, an immediate thermal environment with a temperature of approximately 34° C. (93.2° F.). Upon withdrawal of the electric-heating source (i.e. the battery), the unit  11  returned to the ambient temperature after approximately 12 minutes, which is approximately four times longer than conventional materials. 
     It should be noted that the first and second embodiments of composition thermal energy units  11 , which were constructed in the manner set forth above, had an overall weight in the range from of approximately 40 gm (0.088 lbs) to approximately 60 gm (0.132 lbs). Accordingly, it is readily apparent that composition energy units  11  of the type as set forth above can be mass produced while maintaining a thin, light and comfortable construction. Additionally, each actual unit  11  was repeatedly washed and did not experience any compromised operability. 
     The embodiments shown above are intended to be merely exemplary and those skilled in the art shall be able to make numerous variations and modifications to it without departing from the spirit of the present invention. All such variations and modifications are intended to be within the scope of the present invention as defined in the appended claims.