Abstract:
An integrated inspection apparatus for selectively accepting an electrical cable includes a scotchcast having a housing through which the electrical cable extends. The inspection apparatus further includes a block clamp having a passage formed along its longitudinal axis for accommodating a portion of the electrical cable, the portion the portion of the electrical cable being disposed outside of the scotchcast. The block clamp further includes a cap portion which is selectively actuated to provide a compressive force on the electrical cable without deforming an exterior profile of the block clamp.

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to a pigtailed scotchcast assembly, and deals more particularly with an apparatus that provides for the efficient exchange or replacement of pigtails from a pigtailed scotchcast assembly while also increasing the pulling capacity of the scotchcast assembly. 
   BACKGROUND OF THE INVENTION 
   A pigtailed scotchcast assembly is utilized in those fields requiring either pre- or post-inspection of extended cavities, ducts or piping, such as but not limited to the sewer pipe relining industry. In such fields, it is typically necessary to inspect the condition of an extended cavity through the use of a plurality of electrical components. Cameras, lights, cutters and other components are utilized for this purpose and must each be supplied with electrical power to operate. As these cavities are either too confining, unsafe or otherwise unaccommodating for a human presence, the movement of electrical components along the length of any given cavity must be performed by mechanical means. A pigtailed scotchcast assembly is therefore enlisted to provide electrical power to the various components utilized, while also assisting in pulling such components and their associated electrical wiring through the cavity itself. 
   As is currently known and depicted in prior art  FIG. 1 , a typical pigtailed scotchcast assembly  10  is comprised of a scotchcast  12  having an electrical cable  14  entering one end thereof and a plurality of pigtails  16  exiting the opposing end of the scotchcast  12 . The scotchcast  12  includes a pair of wings  18  each having an anchor hole  20  formed therein for dragging or pulling the pigtailed scotchcast assembly  10  along a cavity or piping. The electrical cable  14  is separated into differing bundles of conductors inside the body of the scotchcast  12  and subsequently emerges from the scotchcast  12  as pigtails  16 . The interior of the scotchcast  12  is filled with a resin and catalyst compound which, when sufficiently dried and cured over time, provides a watertight sealant to the scotchcast  12  and the wire bundles therein. 
   As will be readily appreciated, when the pigtailed scotchcast assembly  10  is dragged or pulled through many cavities or pipes, the pigtails  16 , including the protective sheathing covering the pigtails  16 , tend to wear and become tattered, leading to operational failure of the supported electrical components. In these instances, inspection of the cavity or piping must be halted while the entire scotchcast assembly  10  is severed from the electrical cable  14  and another assembly attached in its place. This method is time-consuming, costly, requires expertise in electronics and must frequently accommodate the recommended 12-hour time period that a typical insulating and waterproofing resin and catalyst compound requires to cure. 
   Another known pigtailed scotchcast assembly  30  is shown in FIG.  2  and was the subject of commonly assigned U.S. Pat. No. 6,250,955, herein incorporated by reference in its entirety. As shown in  FIG. 2 , the two-piece pigtailed scotchcast assembly  30  is comprised of a first portion  32  capable of integrally and selectively mating with a second portion  34 . The first portion  32  includes a central housing  35  from which a plurality of pigtails  36  are adapted to extend. The pigtails  36  each contain a varying number of electrical conductors and terminate in a connection end  38  for connection with various electrical components. 
   Still in reference to  FIG. 2 , the second portion  34  includes a threaded connection piece  46  having a female attachment end  48  and a connecting tip  50 . The female attachment end  48  has exterior threads formed on the outer circumference thereof and further includes a plurality of pin receptacles  52 . The pin receptacles  52  are arranged in number and orientation so as to match and integrally mate with the connection pins  42  of the male attachment end  40 . The male and female attachment ends  40  and  48  respectively, are brought into watertight contact with one another as the threads of the female attachment end  48  are selectively engaged with the inner threads of the operation ring  44 . 
   The connecting tip  50  is equipped with a plurality of outwardly extending female posts  56  which are each utilized to anchor the individual conductors of an electrical cable  58  through a known soldering or crimping process, or the like. 
   Moreover, as shown in  FIG. 2 , a scotchcast  60  is employed through which the electrical cable  58  is fed. The scotchcast  60  is adapted to include a first mating end  62  and a second mating end  64 . An end plug  66  is slidable along the electrical cable  58  and includes a first plug end  65  and a second plug end  67  wherein the first plug end  65  threadedly engages a second mating end of the scotchcast  64 . A seal  68  is also slidably mounted about the electrical cable  58  and provides a watertight barrier when properly seated between the second plug end  67  and the electrical cable  58 . An end cap  70  is slidably mounted about the electrical cable  58  and includes threads formed about the inner periphery thereof so as to threadedly engage with the second plug end  67 . 
   A cut-out  61  is schematically shown in  FIG. 2  to reveal a clamp  80  located within the housing of the scotchcast  60  and centered about the electrical cable  58 . The clamp  80  is formed from a wear resistant material, such as metal or the like, and is held to the electrical cable  58  in a non-slidable fashion, through friction, in any of a number of conventional manners. When the end plug  66  is fully engaged with the second mating end  64 , the electrical cable  58  is prohibited from being pulled free of the scotchcast  60  by the abutment between the clamp  80  and an end face  81  of the first plug end  65 . The clamp  80  therefore greatly increases the pulling capacity of the scotchcast  60 . 
   As also depicted in  FIG. 2 , a tension web  90  extends along the length of the electrical cable  58  and provides additional pulling capacity to the scotchcast  60 . The tension web  90  is typically formed from a weave of metal, nylon or other resilient material and serves to tighten about the electrical cable  58  in proportion to the pull exerted upon the tension web  90 . When utilized as a whole, the clamp  80  and the tension web  90  allow the scotchcast  60  to withstand stresses up to approximately 5000 lbs. of pulling capacity without endangering the integrity of the electrical cable  158 . 
   While effective, it will be readily appreciated that much time and great care had to be employed in order to solder each individual terminal end of the conductors in the electrical cable  58  to the posts  56 , as shown in FIG.  2 . Moreover, once accomplished, these fixed and soldered connections may actually become an impediment should an operator wish to adapt the wiring schematic of the electrical cable  58  to a new application. 
   In addition, the clamp  80  was found to occupy a significant amount of room within the scotchcast  60  while providing only a measured increase to the pulling capacity of the scotchcast assembly  30 . Moreover, the tension web  90  performed well until becoming caught or snagged upon a foreign object which, in turn, would cause the tension web  90  to bunch up and therefore lose much of its pulling capacity. 
   With the foregoing problems and concerns in mind, it would therefore be advantageous to develop a pigtailed scotchcast assembly, which overcomes the above-described drawbacks, thereby accommodating a quick and efficient adaptation of a differing wiring schematic and increased pulling capacity. 
   SUMMARY OF THE INVENTION 
   It is therefore an object of the present invention provide a scotchcast assembly which may allow for efficient exchange or replacement of differing pigtails. 
   It is another object of the present invention to provide a scotchcast assembly, which allows for the exchange or replacement of differing pigtails without the need for special instruments or in-depth electrical knowledge. 
   It is another object of the present invention to provide a scotchcast assembly which allows for the quick and efficient adaptation of a differing wiring schematic. 
   It is another object of the present invention to provide a scotchcast assembly having increased pulling capability. 
   According to one embodiment of the present invention, an integrated inspection apparatus for selectively accepting an electrical cable includes a scotchcast having a housing through which the electrical cable extends. The inspection apparatus further includes a block clamp having a passage formed along its longitudinal axis for accommodating a portion of the electrical cable, the portion of the electrical cable being disposed outside of the scotchcast. The block clamp further includes a cap portion which is selectively actuated to provide a compressive force on the electrical cable without deforming an exterior profile of the block clamp. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a one-piece pigtailed scotchcast assembly, as is commonly known in the art. 
       FIG. 2  illustrates a composite view of a known two-piece scotchcast assembly utilizing soldered connections and a tension web. 
       FIG. 3  illustrates a scotchcast assembly, according to one embodiment of the present invention. 
       FIG. 4  is a side view of a block clamp utilized in conjunction with the scotchcast assembly of FIG.  3 . 
       FIG. 5  is a front view of a block clamp utilized in conjunction with the scotchcast assembly of FIG.  3 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 3  depicts a scotchcast assembly  100  according to one embodiment of the present invention. Although not illustrated in  FIG. 3 , the scotchcast assembly  100  is designed to operatively mate with a pigtail assembly, such as is represented by numeral  32  in prior art  FIG. 2 , and herein incorporated by reference in its entirety. 
   As depicted in  FIG. 3 , the present invention is directed towards a scotchcast assembly  100  which is comprised of a threaded connection piece, or amphenol,  102  having a female attachment end  104  and a connecting tip  106 . The female attachment end  104  has exterior threads formed on the outer circumference thereof and further includes a plurality of non-illustrated pin receptacles. The non-illustrated pin receptacles are arranged in number and orientation so as to match and integrally mate with a matching number of connection pins  42  protruding from the body of the pigtail assembly  32 , as shown in FIG.  2 . 
   The connecting tip  106  also has exterior threads formed on the outer circumference thereof, as well as being equipped with a plurality of outwardly extending posts  108 . As discussed in conjunction with prior art  FIG. 2 , the outwardly extending posts  108  have previously been utilized to accept and anchor the individual conductors of an electrical cable  110  via a known soldering or crimping process, or the like. In contrast with this known arrangement, the scotchcast assembly  100  of the present invention instead utilizes the outwardly extending posts  108  to accept and anchor a matching number of male connectors  112 , also connected via a soldered joint  114 , or the like. 
   As is further shown by  FIG. 3 , the electrical cable  110  includes a plurality of nested, yet separate, conductors  116 . The conductors  116  extend through the scotchcast  118  and protrude from the rear thereof prior to final integration of the scotchcast assembly  100 . Rather than leaving the bare, distal ends of the conductors  116  free to facilitate a soldering action, as was the case in the prior art scotchcast assembly shown in  FIG. 2 , the scotchcast assembly  100  of the present invention instead anchors a matching number of female connectors  120  to the distal ends of the conductors  116 , via a soldering joint  122  or the like. As will be appreciated, the male connectors  112  and the female connectors  120  may be of any size or configuration, provided that they integrally and releasably mate with one another. 
   It is therefore an important aspect of the present invention that the scotchcast assembly  100  does not directly solder or otherwise fixedly attach the bare, distal ends of the conductors  116  to the outwardly extending posts  108 . Instead, the male and female connectors,  112  and  120  respectively, are utilized in order to provide a secure, yet selectively removable, connection between the outwardly extending posts  108  and the conductors  116  of the electrical cable  110 . In this manner, the present invention accommodates a quick and efficient adaptation of any differing wiring schematics which may be necessary. That is, by not having a fixed, soldered connection between the outwardly extending posts  108  and the bare, distal ends of the conductors  116 , the present invention avoids the laborious and time consuming necessity of heating these soldered joints prior to rearranging the connections therebetween. Thus, the selectively removable interface created by the male and female connectors,  112  and  120 , significantly reduce the time and effort needed to adapt to differing schematic configurations without requiring any additional heating or splicing steps. 
   It will be readily appreciated that although  FIG. 3  illustrates three conductors  116  and a matching number of outwardly extending posts  108 , the present invention is not limited in this regard as any number of conductors and matching posts are also contemplated by the present invention. Moreover, although the present invention has stipulated that the outwardly extending posts  108  have the male connectors  112  affixed thereto, while the conductors  116  themselves have affixed thereon the female connectors  120 , the present invention is not limited in this regard as the male and female connectors,  112  and  120 , may be alternatively affixed to either the outwardly extending posts  108 , or the conductors  116 , without departing from the broader aspects of the present invention. 
   The present invention also contemplates the use of shrink-wrap tubing, or the like, which may be slid over the conductors  116  prior to the male and female connectors,  112  and  120 , being affixed. After the male and female connectors,  112  and  120 , are soldered to the posts  108  and the conductors  116 , respectively, the shrink-wrap tubing may then be moved to cover the mated male and female connectors,  112  and  120 , and subsequently shrunk, further insuring that the engagement between the male and female connectors,  112  and  120 , remain intact. When a change is thereafter necessary or desired, the shrink-wrap tubing need only be peeled away to enable the unplugging of the male and female connectors,  112  and  120 . 
   Returning to  FIG. 3 , the female attachment end  104  and the connecting tip  106  are adapted to include interior electrical conduits (unillustrated) for providing a plurality of continuous electrically conductive passages through the connection piece  102 . While the connection piece  102 , as shown in  FIG. 3 , is depicted as a one-piece element, the present invention is not limited in this regard as the connection piece  102  may be alternatively formed by a plurality of electrically interconnected elements without departing from the broader aspects of the present invention. 
   As previously mentioned, the scotchcast  118  includes an inner cavity through which the electrical cable  110  is fed. The scotchcast  118  is further adapted to include a first mating end  124  and a second mating end  126  and provides, inter alia, a watertight protective enclosure for the interface between the connecting tip  102  and the electrical cable  110 . The first mating end  124  is configured to integrally mate with the connecting tip  124  and therefore has a series of non-illustrated threads inscribed about the inner circumference thereof. In addition, the first mating end  124  includes has a series of threads inscribed about the outer circumference thereof for integrally mating with a protective sheath of the pigtail assembly, in accordance with the known embodiment depicted in prior art FIG.  2 . 
   The scotchcast  118  further includes a pair of wings  128 , each having an anchor hole  130  formed therein for dragging or pulling the scotchcast assembly  100  along a cavity or piping. While a pair of wings  128  has been described as facilitating the dragging or pulling of the scotchcast  118  along a cavity or piping, the present invention is not limited in this regard as alternative locations for the anchor holes, such as through the body of the scotchcast  118 , may be utilized without departing from the broader aspects of the present invention. Moreover, other known methods for dragging the scotchcast assembly  100  are also contemplated by the present invention. 
   The second mating end  126  itself has a series of threads inscribed about the inner circumference thereof for securably mating with an end plug  132  which is slidable along the electrical cable  110 . The end plug  132  includes a first plug end  134  and a second plug end  136 , wherein the first plug end  134  threadedly engages the second mating end  126  of the scotchcast  118 . A seal  138  is also slidably mounted about the electrical cable  110  and provides a watertight barrier when properly seated between the second plug end  136  and the electrical cable  110  in a manner to be described in more detail later. 
   A two-piece block clamp  140  is also illustrated in FIG.  3  and is utilized to provide the scotchcast assembly  100  with a significantly greater pulling capacity than has been previously known in the art. Although shown in plan view in  FIG. 3 , the block clamp  140  is designed to have a substantially tubular exterior housing  142  with at least one tapered end  144 . The block clamp  140  includes a first portion  146  including an inner cavity  148  and is adapted for accommodating the electrical cable  110  along longitudinal length thereof. The inner cavity  148  itself defines a series of inscribed inner threads  150  (depicted in phantom lines in  FIG. 3 ) for mating engagement with the external threads of the second plug end  136  of the end plug  132 . 
   Also shown disposed within the inner cavity  148  is a plastic insert  152 . The insert  152  is slidable along the electrical cable  110  and is shaped to conform to the tapered walls  154  of the inner cavity when seated therein. The insert  152  includes a plurality of longitudinally extending arms  156  arranged about the circumference of the electrical cable  110 , and is intended to interact with the seal  138  to assist in the creation of a watertight enclosure for the scotchcast assembly  100 . The seal  138  may be formed to include a series of circumferentially spaced apertures to accept the arms  156  of the insert  152  for increased watertight mating. Moreover, although a plastic insert has been described, the present invention is not limited in this regard as other elastic or resilient materials may alternatively be used for the insert  152  without departing from the broader aspects of the present invention. 
   The block clamp  140  further includes a second portion  158  for accommodating the electrical cable  110  along its longitudinal length. The second portion  158  has a series of threaded bores  160  formed therein which are adapted for mating engagement with suitably sized bolts, or the like, extending through a matching plurality of apertures  162  formed in a cap portion  164 . The cap portion  164  is thereby releasably secured to the second portion  158  and may therefore selectively exert an increasing amount of frictional pressure upon the electrical cable  110  caught therebetween as the bolts are correspondingly tightened. 
   It is therefore another important aspect of the present invention that the block clamp  140  is capable of exerting a substantially increased amount of compressive and frictional force upon the electrical cable  110  disposed therein. Moreover, by enabling the selective and incremental application of increased compression and friction, the block clamp  140  may be equally employed with standard electrical wiring, as well as fiber optic cables that may demand less compression in order to avoid structural damage. 
     FIG. 4  illustrates a side view of the block clamp  140 , while  FIG. 5  illustrates an end view of the block clamp  140 . As seen in  FIGS. 4 and 5 , the block clamp  140  employs the tapered ends  144  so as to reduce the possibility that the block clamp  140  will become snagged during use. Moreover, as best seen in  FIG. 5 , the first portion  146 , the second portion  158  and the cap portion  164  all include a hemispherical passage  166  formed along the longitudinal length of the block clamp  140  in order to accommodate the electrical cable  110  therein. 
   It will be readily appreciated that the size of the hemispherical cavity  166  will be chosen in dependence upon the size, or gauge, of the electrical cable  110  and, more preferably, is typically chosen to be slightly smaller in diameter than the electrical cable  110  to assure a tight fitting compression of the same. Moreover, it will also be readily appreciated that the compressive force of the block clamp  140  is significantly greater than the clamp previously utilized in conjunction with prior art FIG.  2 . That is, by forming the block clamp  140  so as to extend along a predetermined length of the electrical cable  110 , the present invention provides much greater pulling capacity than the clamp utilized in FIG.  2 . Also, the matching plurality of bores  160  and apertures  162  formed in the block clamp  140  provide a level of selective compression that the prior art devices and clamps are incapable of replicating. 
   It is another important aspect of the present invention that the greater pulling capacity given to the scotchcast assembly  100  as a result of the block clamp  140  effectively obviates the need for the tension web of prior art  FIG. 2 , or the like, thus eliminating the possibility that the scotchcast assembly  100  will become snagged as the result of any such tension web during use. 
   It will be readily appreciated that the block clamp  140  may itself have any particular size or shape and may be manufactured from any suitable material, including but not limited to metal, plastic, or the like, without departing from the broader aspects of the present invention. 
   In operation, the electrical cable  110  is initially chosen in dependence upon the desired electrical capacity or application and is threaded through the block clamp  140 , the insert  152 , the seal  138  and the scotchcast  118 . The individual conductors  116  of the electrical cable  110  are then electrically coupled to the female connectors  120  through a soldering action or the like. The internal threads of the first mating end  124  are then selectively mated with the threads of the connecting tip  106  until the first mating end  124  is securely seated against a flange  168  of the connection piece  102 . The second plug end  136  and the seal  138  are subsequently mated with the internal threads  150  of the block clamp  140 , while the second mating end  126  is also mated with the first plug end  134 , thereby effectively sealing the interior of the scotchcast  118  in a watertight manner. 
   Now that the scotchcast assembly  100  has been described in connection with the drawing  FIGS. 3-5 , the benefits and advantages of such a configuration, as compared to the prior art pigtailed scotchcast assemblies illustrated in  FIGS. 1 and 2 , will be readily evident. 
   It should also be understood that the scotchcast  118  may be selectively injected with either a resin compound or a dielectric fluid, so as to further increase the pulling capacity of the scotchcast  118 , as well as reinforcing the hydrophobic environment within the housing of the scotchcast  118 , although such a resin compound is not necessary or, in some cases, even desirable. It will also be readily appreciated that a major aspect of the present invention resides in the ability of the scotchcast assembly  100  to withstand excessive pulling tensions without the need for either a resin filled scotchcast  118  or a tension web, due to the increased compressive and frictional force applied to the electrical cable  110  by the block clamp  140 . 
   While a preferred embodiment has been shown and described, various modifications and substitutions may be made without departing from the spirit and scope of the present invention. Accordingly, it is to be understood that the present invention has been described by way of example, and not by limitation.