Patent Publication Number: US-8125308-B1

Title: Relocatable power tap with surge suppression or surge protection and a method for its manufacture

Description:
BACKGROUND OF THE INVENTION 
     Technical Field of the Invention 
     The present invention relates, generally, to a relocatable power tap with surge suppression or surge protection for the distribution of electrical power, which provides increased safety, as compared to similar electrical devices currently known to the prior art, and a method for the manufacture of the relocatable power tap having built-in surge protection or surge protection of the present invention. 
     More particularly, the present invention relates a relocatable power tap having surge protection or surge suppression for the distribution of electrical power, preferably formed as part of an electrical power strip, along with a method for its manufacture, having improved safety for minimizing, if not outright preventing, an electrical fire or similar occurrence that may otherwise result from overheating. 
     SUMMARY OF THE INVENTION 
     It is, therefore an object of the present invention to provide a relocatable power tap having surge protection or surge suppression for the distribution of electrical power formed as an electrical power. 
     It is a further object of the present invention to provide a relocatable power tap for distribution of electrical power formed as an electrical power strip and having surge protection or surge suppression that is capable of meeting, if not exceeding, standardized industrial safety tests. 
     It is an additional object of the present invention to provide a method for the manufacture of a relocatable power tap having surge protection or surge suppression for the distribution of electrical power formed as part of an electrical power strip. 
     The foregoing and related objects are accomplished by the present invention, which provides a relocatable power tap having surge suppression or surge protection thereby affording improved safety, as compared to similar conventional devices, in which the metal oxide varistors (“MOVs”) of the surge protectors or surge suppressors are encased in cement or concrete, and which relocatable power tap is preferably formed as part of an electrical power strip. The method for manufacturing the relocatable power tap having surge suppression or surge protection of the invention includes the step of encasing the metal oxide varistors (“MOVs”) of the surge protector, or surge suppressor, in cement or concrete, or similar fire-resistant material. 
     MOVs are known to the skilled artisan to have a significant tendency to overheat and catch fire during certain types of surges, thereby creating a safety hazard. Cement or concrete is a low-cost mate-rial that is readily available, fire resistant, and easy to work with, thereby making cement or concrete ideal for use in surge protectors for guarding against fires caused by overheat-ing of MOVs. 
     It is anticipated that by encasing the MOVs of surge protectors, or surge suppressors, in cement or concrete that the resulting article would readily meet, or exceed, industry safety standards, such as those set forth by Underwriters Laboratories Inc. (UL) 1449— UL Standard for Safety for Surge Protective Devices  (3d Edition.) 
     Other objects and features of the present invention will become apparent when considered in combination with the accompanying drawing figures which illustrate certain preferred embodiments of the present invention. It should, however, be noted that the accompanying drawing figures are intended to illustrate only certain embodiments of the claimed invention and are not intended as a means for defining the limits and scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       In the drawing, wherein similar reference numerals and symbols denote similar features throughout the several views: 
         FIG. 1  is a perspective view showing a metal oxide varistor (MOV) encased in cement according to the method of the present invention; 
         FIG. 2  is a perspective view showing multiple metal oxide varistors (MOVs) encased in cement according to the method of the present invention; 
         FIG. 3  is a perspective view of a metal oxide varistor (MOV) with a thermal fuse, the combination of which is encased in cement according to the present invention; and, 
         FIG. 4  is a perspective view of a metal oxide varistor (MOV) covered in cement with the mold still present in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS AND DRAWING FIGURES 
     Turning now, in detail, to the accompanying drawing figures,  FIG. 1  presents a perspective view of a module  10  to be used in a relocatable power tap in accordance with the present invention, in which a metal oxide varistor (“MOV”)  12  is encased in cement  14  or similar hardened material. Wires  16   a ,  16   b , lead to, and from, MOV device  12  within cement  14 . A module  10  may be formed by using a mold for encasing MOV  12  in cement, concrete or similar fire-resistant material, or by dipping the MOV in cement or similar hardening or curing material, and subsequently allowed to harden. 
       FIG. 2  provides a perspective view similar to that of  FIG. 1 , except that the module  10  for use in a relocatable power tap is shown as having a plurality of MOV devices,  12   a ,  12   b ,  12   c , encased within cement  14  with lead wires  12   a ,  12   b ,  12   c ,  12   d ,  12   e ,  12   f , leading from the three MOV devices illustrated in  FIG. 2 . 
       FIG. 3  provides a further perspective view of the module  10  for use in a relocatable power tap of the present invention, in which thermal fuse  18  (or a plurality of thermal fuses) may be encased in cement  14 , along with MOV device  12 , or simply placed in contact with one or more MOV devices  12  which are encased in cement  14 . Lead wires  16   a ,  16   b  lead to, and from, MOV device  12 , while lead wires  20   a ,  20   b  lead to, and from, thermal fuse  18 . 
       FIG. 4  illustrates an alternative, preferred embodiment of the present invention for module  10  for use in relocatable power tap, wherein cement  14  may, for example, first be poured into a mold  22  after MOV device  12  is mounted to a circuit board. Mold  22  may either be removed from the final product or simply retained as an additional reinforcing means, which mold may be comprised of such materials as, e.g., Fiberglass, or reinforced with a reinforcing tape. 
     While only several embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that many modifications may be made to the present invention without departing from the spirit and scope thereof.