Abstract:
A pigtailed scotchcast assembly includes a first portion adapted to have the pigtail extending from one end and a male end oriented adjacent to another end thereof. A second portion comprising a scotchcast adapted to have the electrical cable extending from one end and a female end oriented adjacent another end thereof, is also included so that the first portion and the second portion are capable of mating with one another. The pigtailed scotchcast assembly provides for the efficient exchange or replacement of pigtails from a pigtailed scotchcast assembly. The pigtailed scotchcast assembly is provided for enabling a quick and efficient exchange and replacement or replacement of pigtails from the pigtailed scotchcast assembly without wire splicing or special tools.

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. 
     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 water-tight 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. 
     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 an exchange or replacement of pigtails quickly and efficiently without the need to replace the scotchcast or splice the electrical cable. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention provide a pigtailed scotchcast assembly which may allow for efficient exchange or replacement of differing pigtails. 
     It is another object of the present invention to provide a pigtailed 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 pigtailed scotchcast assembly, which allows for the exchange or replacement of differing pigtails while utilizing a common scotchcast and eliminating the need for splicing the electrical cable. 
     It is another object of the present invention to provide a pigtailed scotchcast assembly having a two-piece design and which includes a device to protect the transitional boundary between the two pieces. 
     It is another object of the present invention to provide a pigtailed scotchcast assembly with increased pulling capability. 
     According to one embodiment of the present invention, a pigtailed scotchcast assembly includes an integrated inspection apparatus for selectively housing therein an electrical cable having a plurality of conductors and terminating in a pigtail. 
     Such an inspection apparatus includes a first portion adapted to have the pigtail extending from one end and including a male end oriented adjacent another end thereof. A second portion, comprising a scotchcast adapted to have the electrical cable extending from one end and including a female end oriented adjacent another end thereof, is also included so that the first portion and the second portion are capable of mating with one another. 
     The inspection apparatus also comprises an end plug and a seal circumscribing the electrical cable wherein the seal is adapted to be located between the scotchcast and the end plug. The end plug is selectively mated with the scotchcast thereby securing the seal within said scotchcast in a water-tight manner. 
     The inspection apparatus may also include a protective sheath adapted to surround an interface between the first portion and the second portion, wherein an outer surface of the protective sheath is substantially coextensive with an outer surface of the scotchcast when the first portion and the second portion are mated to one another. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates a one-piece pigtailed scotchcast assembly, as is commonly known in the art; 
     FIG. 2 is a composite view of a two-piece scotchcast assembly according to one embodiment of the present invention; 
     FIG. 3 illustrates a slide and keyway arrangement incorporated into the two-piece pigtailed scotchcast assembly of the present invention; 
     FIG. 4 is a composite view of a second portion of a two-piece scotchcast assembly, according to another embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As previously discussed, FIG. 1 illustrates a known one-piece pigtailed scotchcast assembly  10  wherein the inner cavity of the scotchcast  12  is sealed in a water-tight manner by the introduction of a known resin and catalyst compound  22 . Owing to this configuration, the electrical cable  14  must be severed from the scotchcast assembly  10 , as indicated by a cut line  24 , during times of operational failure of the pigtails  16 . An expensive, time-consuming and precise series of operations must then be undertaken in order to replace the one-piece pigtailed scotchcast assembly  10  whereby a new pigtailed scotchcast assembly is to be prepared and spliced together with the existing electrical cable  14  prior to the resumption of inspection duties by the scotchcast assembly. 
     As depicted in FIG. 2, the present invention is directed towards a two-piece pigtailed scotchcast assembly  30  which 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 electrical components utilized in fields such as but not limited to the inspection of cavities, pipes or other inaccessible locations. While only two pigtails  36  are shown in FIG. 2, the present invention is not limited in this regard as any number of pigtails may be alternatively accommodated given the specific use of the pigtailed scotchcast assembly  30  without departing from the broader aspects of the present invention. 
     The conductors within each pigtail  36  extend the length of the central housing  35  and are secured in a water-tight manner by the injection of a non-conductive resin and catalyst compound into the interior cavity of the central housing  35 . The non-conductive resin and catalyst compound may be any of a group of known compounds which, when given sufficient time to cure, provides a water-proof and resilient filler for the central housing  35 . Moreover, the conductors of each pigtail  36  may be spliced together, or not, within the central housing  35  before terminating in a male attachment end  40 . The male attachment end  40  comprises a plurality of preferably evenly spaced connection pins  42  representing the conductors within each pigtail  36 . A knurled operation ring  44  circumscribes the central housing  35  and is fixed thereto, in a manner known to those in the art, so as to freely rotate about the circumference of the central housing  35 . The operation ring  44  has threads inscribed about its inner circumference and is selectively operated in order to join the first portion  32  of the pigtailed scotchcast assembly  30  to the second portion  34 , as will be described in more detail later. 
     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 water-tight 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  also has exterior threads formed on the outer circumference thereof, as well as being equipped with a plurality of outwardly extending posts  56  which are utilized to anchor the conductors of an electrical cable  58  through a known soldering process or the like. The female attachment end  48  and the connecting tip  50  are adapted to include interior electrical conduits (unillustrated) for providing a plurality of continuous electrically conductive passages through the connection piece  46 . The connection piece  46 , as shown in FIG. 2, is depicted as a one-piece element, however, the present invention is not limited in this regard as the connection piece  46  may be alternatively formed by a plurality of electrically interconnected elements without departing from the broader aspects of the present invention. 
     The second portion  34  further includes a scotchcast  60  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  and provides, inter alia, a water-tight protective enclosure for the interface between the connecting tip  50  and the electrical cable  58 . The first mating end  62  is configured to integrally mate with the connecting tip  50  and therefore has a series of threads inscribed about the inner circumference thereof. In addition, the first mating end  62  includes has a series of threads inscribed about the outer circumference thereof for integrally mating with a protective sheath  80 , to be discussed in more detail later. 
     The second mating end  64  has a series of threads inscribed about the inner circumference thereof for securably seating an end plug  66  and a seal  68  so as to secure the scotchcast  60  against contamination from water or other debris. The scotchcast  60  further includes a pair of wings  70  each having an anchor hole  72  formed therein for dragging or pulling the pigtailed scotchcast assembly  30  along a cavity or piping. 
     While a pair of wings  70  has been described as facilitating the dragging or pulling of the scotchcast  60  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  60 , may be utilized without departing from the broader aspects of the present invention. Moreover, other known methods for dragging the pigtailed scotchcast assembly  30  are also contemplated by the present invention. 
     In operation, the electrical cable  58  is chosen in dependence upon the electrical capacity desired and is threaded through the end plug  66 , seal  68  and scotchcast  60 , to be electrically coupled to the posts  56  through a soldering action or the like. The internal threads of the first mating end  62  are then selectively mated with the threads of the connecting tip  50  until the first mating end  62  is securely seated against a flange  54  of the connection piece  46 . The end plug  66  and the seal  68  are subsequently mated with the internal threads of the second mating end  64 , thereby effectively sealing the interior of the scotchcast  60  in a water-tight manner. 
     The first portion  32  and the second portion  34  are initially engaged by inserting the connection pins  42  into their respective pin receptacles  52 . As depicted in FIG. 3, the proper orientation of the connecting pins  42  and the pin receptacles  52  are maintained through at least one slide  84  and keyway  82 , formed in the female attachment end  48  and central housing  35 , respectively. The operation ring  44  is then selectively rotated to bring the female attachment end  48  and central housing  35  into water-tight communication with one another. 
     Once mated in this manner, the interface between the first portion  32  and the second portion  34  is further protected against contamination and wear through the operation of the protective sheath  80 , depicted in cut-away fashion in FIG.  2 . The protective sheath  80  is a hollow tube, preferably formed form a highly resilient material such as a metal or the like, and is freely insertable over the pigtails  36  and the central housing  35 . The protective sheath  80  has threads inscribed about the inner circumference of at least one end so as to be selectively engageable with the exterior threads of the first mating end  62 . When so mated, the protective sheath  80 , the first portion  32  and the second portion  34  combine to form the pigtailed scotchcast assembly  30  of the present invention. 
     As will also be appreciated from close inspection of FIG. 2, the protective sheath  80  has an outer diameter, which is substantially equal to an outer diameter  60   a  of the main body portion of the scotchcast  60 . With this configuration, when the protective sheath  80  is fully seated about the first mating end  62 , the outer surface of the protective sheath  80  and the outer surface of the scotchcast  60  will be uniformly coextensive with one another. That is, when fully seated, the transitional area between the protective sheath  80  and the scotchcast  60  will be substantially smooth and continuous. 
     Now that the pigtailed scotchcast assembly  30  has been described in connection with the drawing FIGS. 2-3, the benefits and advantages of such a configuration, as compared to the prior art one-piece scotchcast configuration illustrated in FIG. 1, will be readily evident. 
     After extended use of the two-piece pigtailed scotchcast assembly  30 , the pigtails  36  and connection ends  38  may become worn and tattered to the point where replacement is necessary. Alternatively, an operator may selectively choose to exchange the pigtails  36  with another set of pigtails due to the specific equipment requirements of a particular job. In any case, when replacement or exchange is necessary, an operator need only to disengage the protective sheath  80  from the first mating end  62  of the scotchcast  60 , and similarly disengage the operation ring  44  from the threads of the female attachment end  48 . In this manner, the pigtails  36  may be removed from the pigtailed scotchcast assembly  30  to provide for the subsequent mating for yet another pigtailed element. 
     It is therefore an important aspect of the present invention that this replacement or exchange of a pigtailed element take place without the need of cutting and splicing the electrical cable  58 , thereby reducing the technical knowledge necessary for such an operation. 
     It is another important aspect of the present invention that the existing scotchcast  60  may be reused with another pigtailed element, thereby reducing the cost and waste associated with such an operation. 
     It is another important aspect of the present invention that the replacement or exchange of a pigtailed element may be advantageously accomplished without the need of special equipment or training, further reducing the cost of such an operation. Moreover, the desired replacement or exchange may be accomplished in a fraction of the time previously required, allowing less down-time for both the equipment and the operator on a given job. 
     Furthermore, an operator need no longer wait the time period previously necessary for the resin and catalyst compound to cure before the entire pigtailed scotchcast assembly  30  may be utilized in the pre- or post-inspection of a cavity or pipe. 
     The inclusion of the protective sheath  80  is yet another important aspect of the present invention, as such, an element provides a level of contamination and wear protection to the critical areas of the pigtailed scotchcast assembly  30  heretofore unknown in the art. In addition, the protective sheath  80 , the varying length of which is also contemplated by the present invention, provides an impediment to the flexing of the pigtailed scotchcast assembly  30  in those areas of the pigtailed scotchcast assembly  30  which are most sensitive to such flexing by providing a rigid shaft about these sensitive areas. 
     Moreover, by adapting the pigtailed scotchcast assembly  30  so that the transition between the protective sheath  80  and the scotchcast  60  is substantially smooth and continuous, the present invention eliminates the chance that the pigtailed scotchcast assembly  30  will become snagged upon items or protrusions within the cavity being inspected. In such a manner, the protective sheath  80  is less likely to become dislodged, thereby extending the life of the pigtailed scotchcast assembly  30 . 
     The pigtailed scotchcast assembly  30  illustrated in FIGS. 2-3 is operational without injecting the inner housing of the scotchcast  60  with a non-conductive resin and catalyst compound and has an approximate 500 lb. pulling capacity. The present invention is not limited in this regard, however, as the inner housing of the scotchcast  60  may be injected with either a non-conductive resin and catalyst compound or a dielectric fluid, such as oil or the like, in order to ensure that the inner housing of the scotchcast  60  is maintained in a hydrophobic state. As depicted in FIG. 2, a resin or fluid substance may be injected into the inner housing of the scotchcast  60  via any number of injection apertures  63  formed in the housing of the scotchcast  60 . The injection apertures  63  may be subsequently sealed in any conventional manner, such as by utilizing set screws or the like. 
     By filling the inner housing of the scotchcast  60  with a resin and catalyst compound, the pulling capacity of the scotchcast  60  may be increased from approximately 500 lbs. to approximately several thousands of pounds. In these cases, the pigtailed scotchcast assembly  30  would require heating of the scotchcast  60  in order to liquefy the injected resin compound prior to replacing the electrical cable  58 , should replacement become necessary. 
     FIG. 4 illustrates another embodiment of a second portion  134 , whereby the pulling capacity of the pigtailed scotchcast assembly  30  is substantially increased. As seen in FIG. 4, a female attachment end  148  threadedly engages a first mating end  162  of the scotchcast  160 . An end plug  166  is slidable along an electrical cable  158  and includes a first plug end  165  and a second plug end  167  wherein the first plug end  165  threadedly engages a second mating end of the scotchcast  160 . A seal  168  is also slidably mounted about the electrical cable  158  and provides a water-tight barrier when properly seated between the second plug end  167  and the electrical cable  158 . An end cap  170  is slidably mounted about the electrical cable  158  and includes threads formed about the inner periphery thereof so as to threadedly engage with the second plug end  167 . 
     A cut-out  161  is schematically shown in FIG. 4 to reveal a clamp  180  located within the housing of the scotchcast  160  and centered about the electrical cable  158 . The clamp  180  is formed from a wear resistant material, such as metal or the like, and is held to the electrical cable  158  in a non-slidable fashion, through friction, in any of a number of conventional manners. When the end plug  166  is fully engaged with the second mating end  164 , the electrical cable  158  is prohibited from being pulled free of the scotchcast  160  by the abutment between the clamp  180  and an end face  181  of the first plug end  165 . The clamp  180  therefore greatly increases the pulling capacity of the scotchcast  160 . 
     Also depicted in FIG. 4 is a tension web  190 , which extends along the length of the electrical cable  158  and provides additional pulling capacity to the scotchcast  160 . The tension web  190  is typically formed from a weave of metal, nylon or other resilient material and serves to tighten about the electrical cable  158  in proportion to the pull exerted upon the tension web  190 . When utilized as a whole, the clamp  180  and the tension web  190  allow the scotchcast  160  to withstand stresses up to approximately 5000 lbs. of pulling capacity without endangering the integrity of the electrical cable  158 . 
     It should be understood that a combination of the features depicted in FIGS. 2-4 may be assimilated in a pigtailed scotchcast assembly of the present invention. Moreover, the scotchcast  160  may also be injected with either a resin compound or a dielectric fluid, so as to further increase the pulling capacity of the scotchcast  160 , as well as reinforcing the hydrophobic environment within the housing of the scotchcast  160 . It will, however, be readily appreciated that a major aspect of the present invention resides in the ability of a pigtailed scotchcast assembly equipped with either, or both, a clamp  180  and a tension web  190 , to withstand excessive pulling tensions without the need for a resin filled scotchcast  160 . 
     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.