BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a perspective view of a patient suffering from hypothermia on a stretcher showing the pad of this invention placed on the patient's thorax and the plurality of power sources that can be selected to provide power to heat the pad.
FIG. 2 illustrates a perspective view of the pad of this invention with portions cutaway to show its internal construction.
FIG. 3 illustrates the carrying bag of this invention showing it being used to heat a body infusion fluid container.
FIG. 4 illustrates the recharging of the rechargeable battery pack of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
FIG. 1 illustrates the use of pad 10 of this invention placed on patient 16 positioned on stretcher 14 after rescue from a situation where the patient has been exposed to low temperatures and is suffering from hypothermia. In a preferred embodiment pad 10 can be substantially rectangular in shape and measure approximately 40×60 cm in size which is sufficient to cover most adult-size thoraxes. Pad 10 can be placed either flat or folded in half or into quarters directly on thorax 18 or torso of patient 16 under the clothing to warm the patient. Electrical power is received from one of three power sources, a selected one of which is attached to cable connector 21 of input cable 20, such input cable having first wire 52 and second wire 54, as seen in FIG. 2, which input cable 20 extends to pad 10. One type of power supply connected to cable connector 21 can be delivered from an existing local power supply into which plug 25 can be plugged. Such power, being either 110 volt or 230 Volt AC at 50/60 Hz, runs to converter 15 which converts the local power supply voltage to 12 volts AC to pad 10 through cable connector 21. The second type of power supply connector carried in the kit, is a 12 volt DC automobile cigarette lighter type plug 32 which can plug into a cigarette lighter of a vehicle. Cigarette lighter connector 28 can be plugged in turn into cable connector 21 so that pad 10 can be operated off an automobile cigarette lighter or other power supply having a similar cigarette lighter receipt aperture. The third type of power supply connector included in the kit of this invention is a rechargeable battery pack 34, as seen in FIGS. 1 and 4. In one embodiment battery pack 34 can be a 14.5 volt DC lithium ion battery which has approximately a 2.5 hour lifespan. Battery pack 34 can be attached by battery connector 30 to cable connector 21 to provide power to pad 10.
As seen in FIG. 2, the construction of pad 10 includes an outer cover 76 having a bottom member 80 from which upper member 82 has been separated for illustrative purposes, exposing sandwich 78. Sandwich 78 is composed of a first felt-like layer 84 and an attached second felt-like layer 86 which layers enclose the carbon fiber heating elements of the pad. The internal construction of pad 10 of this invention includes first carbon fiber band 40 and second carbon fiber band 42 located, respectively, on opposing first and second sides of pad 10. First and second carbon fiber bands 40 and 42 are each approximately 15 mm wide and each contain 1,000-12,000 carbon microfibers. First wire 52 from input cable 20 extends to wire 96 which runs to first thermal sensor 24, and wire 96 extends from thermal sensor 24 to second carbon fiber band 42. Wire 96 is stripped so that its wire filaments extend down the entire second carbon fiber band 42 and are held in contact therewith by stitching through first felt-like layer 84 and second felt-like layer 86. Heater fiber carbon cross members 44, which are approximately 5 mm wide, extend in a series and are separated from one another by approximately 5 cm. They extend from first carbon fiber band 40 across the pad to second carbon fiber band 42. Second wire 54 coming out of input cable 20 interconnects to second thermal sensor 26 through wire 92, and wire 94 extends from second thermal sensor 26 to first carbon fiber band 40 so as to complete a parallel circuit when electrical current is provided, causing the carbon fibers heating elements to act as 5 ohm resistance at 2-3 amps at 30-35 W and provide heat at the outer surfaces of the pad. Wire 94 is also stripped, exposing its wire filaments that extend in contact with first carbon fiber band 40 to better make electrical contact therewith and with heater cross carbon fiber members 44. First and second carbon fiber bands 40 and 42 as well as heater cross carbon fiber members 44 are sandwiched between first felt-like layer 84 and second felt-like layer 86 which felt-like layers can be adhered to one another such as by stitching through first and second carbon fiber bands 40 and 42 to form a substantially rectangular sandwich 78. In FIG. 2 one corner is shown peeled apart for illustrative purposes, exposing the carbon fiber bands and cross members. Sandwich 78, holding first and second carbon fiber bands 40 and 42 along with heater cross carbon fiber members 44, is contained within the outer covering having upper member 82 and bottom member 80 which can be heat-sealed at their edges to one another beyond the edges of sandwich 78. Sandwich 78 can have an aperture defined at each of its four corners, such as first aperture 88, second aperture 90, third aperture 92, and fourth aperture 94, through which apertures upper member 82 can be heat-sealed to bottom member 80 so as to better retain sandwich 78 within upper and lower members 82 and 80 and prevent sandwich 78 from moving or folding separately from outer cover 76. Upper and lower members 82 and 80 can be made of a soft, bio-compatible PVC material. First and second thermal sensors 24 and 26, as seen in FIG. 1, are self-resetting bi-metallic thermal sensing limit switches and are provided to prevent pad 10 from overheating. First and second thermal sensors 24 and 26, both of which can be self-resetting bi-metallic switches, are spaced apart from one another on opposite outer sides of sandwich 78 with first thermal sensor 24 having a limit of 33/35° C.+/−2° C. and second sensor 26 having a limit of 38/40° C.+/−2° C. First thermal sensor 24 checks that the pad, even when folded in half to a size of approximately 20×30 cm or folded in quarters, does not reach a temperature above 35° C. when it is applied to hypothermia patients. Second thermal sensor 26 acts at a somewhat higher temperature should there be a failure of first thermal sensor 24. First and second thermal sensors 24 and 26 can be positioned on each side of sandwich 78 such that when the pad is folded along plane line 100, the sensors are spaced so as not to overlap on top of one another.
FIG. 3 illustrates carrying bag 74 of the kit of this invention having first and second sides 60 and 62, each having a strap, which carrying bag can be closed by a zipper or other equivalent means of closure. Pad 10 can be contained within second side 62 under second strap 56, when in a storage mode, and the other components of the carrying bag, such as battery charger 64, power connector 66 not shown in FIG. 3, and battery pack 34, as shown in dashed lines, can be held under either first and second straps 56 and 72 when it is stored during nonuse. Pad 10 in FIG. 3, as described below, is shown being used in its second mode of use to warm up body infusion fluid container 58. As such, the power supply connectors would not be left therein so that battery pack 34 is shown in dashed lines to indicate where the power supply connectors would be stored when the carrying bag 74 is used in its storage mode.
In the second mode of usage carrying bag 74, which can be made of nylon or corduroy and have a reflective safety strip on the exterior thereof, can be utilized to warm body infusion fluid containers to be introduced into the body of a patient as it is undesirable to enter fluids that are too cold into a patient. These body infusion fluid containers, such as the body infusion fluid bag 58, as seen in FIG. 3, can be warmed by wrapping one or more of them in pad 10. First and second sides 60 and 62 of carrying bag 74 can be insulated and lined on their inner sides with metallic foil which together act as a heat-reflective, thermally insulating material. When carrying bag 74 is closed, holding heat within the carrying bag, pad 10 warms body infusion fluid bag 58 as well as other body infusion fluid container(s) that are placed within folded pad 10.
Carrying bag 74 when in its storage mode can contain battery charger 64, as seen in FIG. 4. Battery pack 34 can be recharged by placing it in battery charger 64 which is attached to converter 64 which is attached by means of plug 68 to a power source, such as house current and the like. Passing electricity through power converter 66 cuts the house current down to 12 volts so as to recharge battery pack 34 so that the battery can be ready for future use. The pad and other components of the kit of this invention can be easily cleaned and then repackaged in the carrying bag of the kit of the invention so that they are ready for use to warm a patient suffering from hypothermia back to normothermia and to warm up body infusion fluid containers.
Although the present invention has been described with reference to particular embodiments, it will be apparent to those skilled in the art that variations and modifications can be substituted therefor without departing from the principles and spirit of the invention.
Patent Application
20080093356
