Patent Publication Number: US-2006011599-A1

Title: De-icing cable jig construction

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      This invention was the subject matter of Document Disclosure Program Registration Number 546,767, filed in the United States Patent and Trademark Office on Feb. 13, 2004.  
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
      Not applicable.  
     REFERENCE TO MICROFICHE APPENDIX  
      Not applicable.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to the field of roof de-icing arrangements in general and in particular to a de-icing apparatus that can be retrofitted onto existing roof drain constructions.  
      2. Description of Related Art  
      As can be seen by reference to the following U.S. Pat. Nos. 3,784,783; 3,816,687; 6,225,600; 5,960,590; and, 4,333,444, the prior art is replete with myriad and diverse snow and ice melting arrangements for roofs, gutters, drains and the like.  
      While all of the aforementioned prior art constructions are more than adequate for the basic purpose and function for which they have been specifically designed, they are uniformly deficient with respect to their failure to provide a simple, efficient, and practical de-icing arrangement that is adapted to be secured to existing drain components for a floating membrane roof where penetrating anchors cannot be employed.  
      As most building owners and roofing contractors in cold weather climates are all too well aware, ice dams are an ever present danger during the winter months wherein, undue stress loads are placed on generally flat roof constructions.  
      As a consequence of the foregoing situation, there has existed a longstanding need for a new and improved de-icing cable jig construction that can be retrofitted onto existing conventional roof drain constructions, as well as, installed as original equipment on new floating membrane roofs, and the provision of such a construction is a stated objective of the present invention.  
     BRIEF SUMMARY OF THE INVENTION  
      Briefly stated, the de-icing cable jig construction that forms the basis of the present invention is specifically designed for use with floating membrane roof drains provided with a conventional clamping collar and strainer.  
      As will be explained in greater detail further on in the specification, the cable jig construction comprises in general a base plate unit, a cable track unit and a heater cable unit that are operatively disposed intermediate a conventional roof drain, and a membrane clamping collar and strainer arrangement.  
      The base plate unit is provided with a first plurality of enlarged track arm recesses that are dimensioned to receive the plurality of adjustable track arms of the cable track unit and a second plurality of radial drainage slots wherein, the base plate unit assumes the role of the prior art clamping collar on existing floating member roof surfaces.  
      In addition, each of the track arms of the track unit defines a pair of heating cable channels dimensioned to receive individual horizontal heating cable loops wherein, the track unit further includes a central hub element dimensioned to receive a downwardly depending vertical heating cable loop that extends through the mouth of the drain pipe. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
      These and other attributes of the invention will become more clear upon a thorough study of the following description of the best mode for carrying out the invention, particularly when reviewed in conjunction with the drawings, wherein:  
       FIG. 1  is a perspective view of the de-icing cable jig construction installed on a floating membrane roof surface;  
       FIG. 2  is a cross-sectional view taken through line  2 - 2  of  FIG. 1 ;  
       FIG. 3  is an exploded perspective view of the cable jig construction and conventional roof drain components;  
       FIG. 4  is an isolated perspective view of the cable track unit and the heating cable unit as viewed from above;  
       FIG. 5  is a cross-sectional view taken through line  5 - 5  of  FIG. 4 ;  
       FIG. 6  is an isolated perspective view similar to  FIG. 4 , but viewed from below; and,  
       FIG. 7  is a perspective view of the structural components of the jig construction in combination with the prior art clamping collar. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      As can be seen by reference to the drawings, and in particularly to  FIG. 3 , the de-icing cable jig construction that forms the basis of the present invention is designated generally by the reference number  10 . The construction  10  comprises in general a base plate unit  11 , a cable track unit  12  and a heating cable unit  13  employed in combination with a conventional floating membrane roof drain  100 , a conventional clamping collar  110  and a conventional domed strainer  120 . The aforementioned units will now be described in seriatim fashion.  
      As can best be seen by reference to  FIG. 7 , the base plate unit  11  comprises a circular base plate member  20  provided with a first plurality of enlarged track arm recesses  21  and a second plurality of drainage slots  22  arranged in a radial fashion around an enlarged central base plate opening  23 .  
      In addition, as can be seen by reference to  FIGS. 4, 6  and  7 , the cable track unit  12  includes a hollow hub member  30  provided with a plurality of radial track arms  31  wherein, each of the track arms  31  is provided with an adjustable outer sleeve element  32  wherein, the exterior surface of the sides of the track arms  31  and the interior surface of the sides of the sleeve elements  32  define a pair of cable track channels  33  the purpose and function of which will be described in greater detail further on in the specification.  
      Turning now to  FIGS. 1 through 4  and  6 , it can be seen that the heating cable unit  13  comprises an elongated length of heating cable  40  that is threaded into the channel tracks  33  between the radial arms  31  and radial sleeve elements  32  to define a plurality of horizontally arrayed heating cable loops  41   41  and wherein, the heating cable  40  is further threaded through the hub member  30  of the cable track unit  12  to define a vertically oriented downwardly depending cable loop  42  that extends into the conventional drain pipe  100  to prevent ice buildup in the mouth and throat portions of the drain pipe  100 .  
      Furthermore, as can be seen by reference to  FIGS. 3, 4  and  7 , this invention also contemplates the provision of a cap plate member  50  that cooperates with the base plate member  20  to captively engage the cable track unit  12  intermediate the clamping collar with the associated  110  domed strainer  120  and the roof drain  100  which are normally directly connected to one another in a well recognized fashion.  
      As can also be appreciated by references to  FIGS. 4 and 5 , this invention also contemplates the provision of alignment tines  60  that are operatively associated with both the base plate member  20  and the cap plate member  50  to align the apparatus  10  with the mouth of the drain pipe  100 .  
      Although only an exemplary embodiment of the invention has been described in detail above, those skilled in the art will readily appreciate that many modifications are possible without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims.  
      Having thereby described the subject matter of the present invention, it should be apparent that many substitutions, modifications, and variations of the invention are possible in light of the above teachings. It is therefore to be understood that the invention as taught and described herein is only to be limited to the extent of the breadth and scope of the appended claims.