Abstract:
A conforming heating pad having a curvilinear Y-shaped recess has a pair of opposed curved wing sections surrounding a centralized opening occupied by a central flap portion created by the Y-shaped recess. A pair-of opposed multi-layer constructions housing a resistive NTC sensing wire and a plurality of individual weights serve to enhance the conformity of the heating pad. The heating pad is operable in at least two modes, including a constant heating level mode at various user-selectable temperature levels and a timed mode that offers user-selectable temperature levels over a user-selectable period of time. The heating pad can be wetted to offer a moist heat therapy.

Description:
FIELD OF THE INVENTION 
       [0001]    The present disclosure is related generally to electrically heated pads. In particular, the present disclosure is directed to a conformable heating pad optimized to better conform to the varying contours of the human body and to provide either a consistent or a cycled level of heat. 
       BACKGROUND OF THE INVENTION 
       [0002]    The statements of this section merely provide background information related to the present disclosure and may not constitute prior art. 
         [0003]    Medical research has shown that heat therapy over an extended period of time can provide significant benefits for patients experiencing muscle and soft tissue cramping, pulls or strains. It is well understood that heat therapy provides several benefits for simple injuries, including the stimulation of the sensory receptors in the skin thus causing the heat to serve as an analgesic (i.e., reducing the transmission of pain signals to the brain), a relaxation of the soft tissues and a reduction of joint stiffness in the area of the treatment, and the vasodilation of the blood vessels in the treated area. 
         [0004]    Vasodilation is a physical response to a localized increase in temperature. The response has several distinct parts. The first three to five minutes of the reaction are generally attributed to a nervous system reaction which is characterized by the relaxation of the muscle tissue immediately surrounding the local blood vessels thus allowing the vessels to expand and is further characterized by a significant increase in blood flow to the treated area. After this initial nervous system response, blood flow decreases moderately for a short period of time and is immediately followed by a gradual increase in blood flow until a sustained higher than normal level of blood flow to the area is reached after approximately 25-30 minutes of treatment. Clinical studies have determined that the ideal temperature to achieve full vasodilation is approximately 108° F., but must be at least 102° F. in order to obtain any benefits from an extended heat therapy. 
         [0005]    While such heat treatment can enhance healing, it has been known that a moist heat will penetrate the body&#39;s tissues deeper than the dry heat generally provided by the common heating pad. Further, in order to optimize a heat treatment, the thermal transfer between the heating pad and the user must be maximized. Generally, common heating pads are limited to basic square or rectangular shapes that do not readily conform to the complex geometry of the human body, and in particular do not readily conform to various joints (i.e., shoulders, elbows, knees, neck, lap, etc.) which are often the locations requiring such treatment. Further, commonly available electrically heated pads are generally not well suited for delivery of moist heat. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    A conformable heating pad is specifically shaped and suited for use on the complex geometries of the human body. In particular, a weighted heating pad is shaped to enhance the conformity with the region of the body with which it is engaged and thus enhancing the heat transfer between the pad and the user&#39;s body. Further, the present invention allows for the introduction of moisture to the product for the generation of an increased area of humidity between the pad and the user&#39;s body thus resulting in an improved heat transfer and therapeutic treatment. 
         [0007]    The heating pad may include a multi-layer construction of successive layers of electrically non-conductive materials separated by a non-woven batting. Two of such opposed multi-layer constructions may be sandwiched about a resistive heating element. The element may be located in grooves formed in the inner layer of one of the constructions. A plurality of individual weights may be affixed to the inner layer of the same or the opposing construction. The predetermined pattern of the heating element may be such that the individual weights are located between the various loops in the element further assuring a uniform thermal distribution across the pad. 
         [0008]    The heating pad may operate in two primary modes—a consistent heat mode and a timed mode. As designated by the user, the heating pad may be capable of providing a consistent level of heat based upon the selected setting of a separable controller or may provide a heat treatment at a user-defined heat level for a user-selected period of time. It should be noted that both modes are operable regardless of whether a user chooses to use the pad to supply a dry heat or through the introduction of moisture to the pad surface to supply moist heat to the treatment area. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    A more complete appreciation and many of the attendant advantages of the heating pad will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein similar reference numbers refer to similar elements. 
           [0010]      FIG. 1  shows an overhead view of an embodiment of a heating pad; 
           [0011]      FIG. 2  shows an exploded view of a heating pad construction; 
           [0012]      FIG. 3  shows one exemplary pattern for both the heating element and the plurality of individual weights used in a heating pad; 
           [0013]      FIG. 4A  shows an exemplary heating pad in use on the lap of a user; 
           [0014]      FIG. 4B  shows the exemplary heating pad of  FIG. 4A  in use on the lower back of a user; 
           [0015]      FIG. 4C  shows the exemplary heating pad of  FIGS. 4A and 4B  in use on the knee of a user; and 
           [0016]      FIG. 4D  shows the exemplary heating pad of  FIGS. 4A ,  4 B, and  4 C in use on the shoulder of a user. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0017]    While the heating pad may be susceptible to embodiment in different forms, herein will be described in detail, embodiments with the understanding that the present description is to be considered an exemplification of the principles of the invention and is not intended to limit the scope of the appended claims to that as illustrated and described herein. Instead, it is envisioned that those skilled in the art may devise various modifications and equivalents without departing from the spirit and scope of the appended claims. 
         [0018]    A weighted therapeutic heating pad  10  as seen in  FIG. 1  includes a generally circular shaped pad having a curvilinear Y-shaped slot  12  therein. The Y-shaped slot  12  divides the pad  10  into a main body portion  14 , a first curved wing section  16 , a second curved wing section  18  opposite the first wing section  16 , a central opening  20  situated between the main body portion  14  and the curved wing sections  16  and  18 , and a flap portion  22  located within the central opening  20 . As part of the enhanced flexibility of the pad  10  there is provided a plurality of securing means  24  about a surface of the pad  10 , such as at free end portion  21 , to allow for overlap of the curved wing sections  16  and  18  and to allow for securing the flap portion  22  to the main body  14  leaving the vacant central opening  20 . The securing means  24  can be snaps, buttons, clasps, hook and loop fabric, and any other releasable fasteners. 
         [0019]      FIG. 2  shows an exploded view of a therapeutic heating pad  10  including a pair of opposed multi-layer constructions  24 . Each multi-layer construction  24  includes an outer shell  26  and a scrim  28  separated by a layer of a batting material  30 . The batting material  30  is included to both enhance the comfort of the pad  10  during its use, as well as to provide an air-insulation layer within the constructions  24 . The opposed constructions  24  are layered or sandwiched around a resistive heating element  32  and a plurality of individual weights  34 . The individual weights  34  can be formed of ceramic pellets. Further, to provide adequate weight to enhance the conformability of the pad  10 , it is preferred that the weight of all of the individual weights  34  total between generally about one and three pounds, more preferably two pounds. 
         [0020]    Without some mechanism for retaining the heating element  32  in its designated pattern between the scrims  28 , any physical manipulation of the heating pad  10  could result in its displacement. Such displacement could result in a crimping of the heating element  32  or significantly reduce the effectiveness of the pad  10  by reducing the uniform thermal distribution inherent in the heating element  32  layout. In order to secure the heating element  32  in place, it is preferred that the at least two opposed scrims  28  are secured to each other in such a manner as to produce retaining channels  36  through which the various loops of the heating element  32  are run as it traverses its path within the heating pad  10 . Individual pockets  38  of varying numbers of the individual weights  34  are also preferably located between the loops of the heating element  32  throughout the heating pad  10 . The individual weights  34  can be loose individual weights or packets, pouches, or flexible tubes of a desired number of weights so as to keep the weights together and make manufacturing of the heating pad easier. Additionally, the outer periphery of all the various layers with the two opposed constructions  24  are secured together to complete the manufacture of the heating pad  10 . 
         [0021]    The outer shells  26  and the scrims  28  include an electrically non-conductive, heat-resistive sheet material. Such material is preferably a polymer, such as polyester, polyvinyl chloride, or polypropylene. 
         [0022]    In an effort to enhance the safety of the device during operation, and as best seen in  FIG. 3 , the heating element  32  of the present invention can be formed of positive or negative temperature coefficient wire capable of sensing temperature differentials along its length such that it serves as a plurality of discrete sensors capable of detecting localized hot spots. Operation of such wires is well known in the art and is discussed in greater detail in U.S. Pat. No. 7,180,037, issued to Weiss on Feb. 20, 2007, and which is fully incorporated herein by reference. 
         [0023]    The heating pad additionally includes a cord set  40 ,  42 , and  44 , and a controller  46 . Cord  40  is for connection to a power supply (not shown), including but not limited to a 110V or 220V wall outlet and is secured at the opposite end to controller  46  for delivery of electrical power thereto. Cord  42  is secured at one end to controller  46  and has a releasable connector  44  at the opposite end. Connector  44  may be one of any known type of releasable electrical connections, including, a snap-lock connector  44  that corresponds to a receptacle  48  extending from the periphery of pad  10  and into which the ends of the looped heating element  32  are secured. 
         [0024]    Controller  46  includes a microprocessor and its internal clock (not shown) which function to vary the electrical draw required to increase or decrease the thermal output of the resistive heating element  32  in accordance with a user-selected setting, as well as serving to limit the operation of the pad  10  during its timed mode of operation. The controller  46  further includes an activator  50  to control all of the functions of the pad  10  through the manipulation of one or more switches. 
         [0025]    The activator  50  may include any of the many known types of rotary or switch type devices suitable for operating a multi-setting electrical appliance. Controller  46  can include a four position “jog”-type switch  50 . One setting of the switch  50  is indicated as “OFF”. When in this position jog switch  50  prevents electricity flow to the pad  10  via cord  42  and connector  44 . Transition of the jog switch  50  into any other position will automatically activate the pad  10 . In a second and third position, the jog switch  50  serves to allow the user to transition “UP” or “DOWN” through the multiple user-selectable heat settings. The jog switch  50  may be used to activate the timed mode of operation of the pad  10  by moving the switch  50  to the “STAY ON” setting. When this mode is activated, the switch  50  settings corresponding to “UP” and “DOWN” serve to transition the user through the multiple user-selectable time periods available for set periods of activation of the pad  10  until such time that the period of activity has been chosen and then they will revert back to allowing the user to transition through the available temperature settings. 
         [0026]    In operation, the pad  10  is capable of operating in three different modes. First, the pad  10  can be activated to offer a consistent level of heat based on a user-selected setting from those available. The controller  46  preferably includes a digital display  52  capable of showing the presently selected temperature level and/or the available time durations during operation of the pad  10  in the timed mode. 
         [0027]    Second, the pad  10  can be activated to offer a timed mode. During operation of the pad  10  in the timed mode, the pad will be active for only a user-selected period of time before being automatically turned off, however, the user is still able to set or alter the temperature level provided by the pad  10  during such given period of time using the controller  46  as discussed above. 
         [0028]    Third, the pad  10  may be operated in either of the first or second mode such that the pad  10  provides the user a moist heat. In this mode of operation, no alternative switch settings are required beyond that discussed above. Instead, the pad  10  is can be constructed of materials that allow for the heating pad to be submerged in or exposed to water so as to moisten or soak the pad  10 . After such treatment, the retained moisture in the various layers of the pad  10  adds humidity to the heat treatment making it a moist heat therapeutic treatment. 
         [0029]    To enhance the therapeutic capability of the pad  10 , it is preferred that the controller  46  provide at least eight user-selectable temperatures, including a “HIGH” and a “LOW” setting and six settings in-between. The temperature range across all of the available settings ranges from generally about 85° F. on the “LOW” setting to generally about 165° F. on the “HIGH” setting. Further, it is preferred that the available user-selectable time periods for the timed mode of operation range from one-half hour to at least four hours in half hour increments. 
         [0030]    As best seen in  FIGS. 4A-D , the curved wing sections  16  and  18  and the central flap portion  22  work in coordination with the main body  14  to wrap around the three dimensional curved shapes associated with the joints and other portions of the human body most often requiring heat-based therapy. As discussed above, in order to further aid the weighted pad  10 , there are provided a plurality of securing means  24  about an upper surface of the heating pad  10  to allow overlapping of the curved wing sections  16  and  18  and/or for securing the central flap portion  22  to the main body  14  so as to expose the central opening  20 . With the wing portions  16  and  18  secured together and the central opening  20  exposed, appendages, such as an arm, leg or head can be passed through the central opening  20  so as to allow for additional application of the heating pad  10  to areas of the body including the back of the thighs, the ribs, or the upper back without requiring the user to hold the pad  10  in place. 
         [0031]    Those skilled in the art can now appreciate from the foregoing description that the broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure-includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the disclosure.