Abstract:
A system and method for making a repair to a damaged section of a conduit includes a pair of couplers, which securely mate, with undamaged sections of the conduit, which straddle the damaged section of the conduit; and a bridging duct, which replaces the damaged section. In one embodiment, the couplers are placed around the undamaged section of the conduit and the bridging duct is placed around the couplers.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to conduits. Specifically, the present invention relates to repairing and/or reinforcing conduits. 
     2. Description of the Prior Art 
     Modern utility companies provide resources to end-users. The resources may include energy or power, communications capability or even water. The various resources are communicated from the utility company to the end-user through infrastructure. The infrastructure may include conduits to protect the power lines, the communications lines or to carry the water. The conduits or piping are typically referred to as a utility conveyance or utility conduit. Further, piping may be placed within the conduits or the duct. The piping placed within an outer duct or conduit may be referred to as an inner conduit. 
     During the installation of a utility conduit, a trench is prepared for housing the conduit. The conduit is then positioned in the trench. Once the conduit is in place, the utility lines such as power lines or communications lines are pulled through the conduit from one termination point to another. The conduits are then covered or buried within the trench. 
     The conduit may be damaged during installation or after installation. For example, the conduit may be placed in the trench prior to pulling the utility lines through the conduit. As a result, dirt and debris such as rocks may impact the conduit and cause damage to the conduit. After the utility lines have been placed in the conduit and the trench is covered, damage may still occur to the conduit from forces bearing down from above. Once again this may cause damage to the utility conduit. 
     Working utility inner conduits, such those used to collocate fiber optic cable strands, are housed in a variety of ducts to protect them from the harsh earth environments in which they are installed. Quite often they are housed in flexible conduit such as manufactured from PVC or Polyethylene. This affords easy installation of the inner conduit and protects it from compromising conditions stemming from unstable soil, rights of way bearing heavy traffic and areas deemed by cable engineers as stress ridden. The installation of the inner conduit is very costly, both in time and money. Consequently, it is imperative that the integrity of the conduit be maintained at all times and that damages to the flexible conduit be properly repaired. 
     As mentioned previously, once the conduit is placed in a trench prepared therefor, damage to a section of the conduit can occur before or after the inner conduit is laid. In either case, the damaged section of the conduit must be replaced to ensure its viability for protecting the inner conduit from the harsh environment. Should the damage precede laying of the inner conduit, replacement of the damaged section may be required to eliminate any bends or kinks which would interfere with passing the inner conduit through the utility conduit. 
     The conventional method for repairing a damaged section of a conduit is to remove the damaged section by splicing and replace it with a new piece of matching conduit. FIG.  1  and FIG. 2 display how this is done. As shown in FIG. 1, a flexible conduit  100  has a working utility inner conduit  102  consisting, for example, of fiber optic cable strands. FIG. 1 displays that conduit  100  has sustained damage in a section generally shown by reference numeral  104 . 
     FIG. 2 displays the present method for repairing the damaged section of a conduit. In FIG. 2, damaged section  104  has been removed by splicing, leaving inner conduit  102  unaffected. A new section  200  having the same diameter and length has replaced the damaged section  104  of FIG.  1 . New section  200  is inserted between the adjoining undamaged sections  202  of conduit  100  by slitting the conduit  100  lengthwise and placing the new section  200  around the exposed inner conduit  102 . New section  200  is affixed to the adjoining undamaged sections  202  of flexible conduit  100  using duct tape  204  or some other fastening mechanism such as glue, etc. 
     The conventional method for repairing a damaged section of a flexible conduit is simple, but very unreliable. First, it does not provide any rigidity where the new section  200  is joined to the adjoining undamaged sections  202  of the conduit  100  with tape  204 . Thus, the new section  200  is subject to collapse from the pressure of the dirt when ground cover is placed on top of the conduit  100 . The ground cover does not only put pressure on the inner conduit  102 , but it would also allow debris to find its way into the inner conduit  102 , thereby jeopardizing its utility and integrity for future use. 
     Thus, a more effective method and apparatus for repairing and reinforcing a section of conduit is needed. 
     SUMMARY OF THE INVENTION 
     The present invention comprises a system and method for repairing a conduit by bridging two sections of the conduit with a bridging duct. A pair of couplers is employed to mate the bridging duct with the two sections of the conduit. First, the couplers are mated to their respective sections of the conduit. Thereafter, the bridging duct is mated with the couplers and fastened using a clip or sealing mechanism. 
     In one embodiment, the bridging duct has a slit along its length and opposing walls along the slit. The opposing walls along the slit create a reliable seal for affording rigidity and serve as a barrier to debris once the bridging duct is in place. Clips and adhesive are used to effect the seal by bringing the opposing walls together. 
     The bridging duct is affixed to the adjoining undamaged sections of the conduit through a pair of couplers, each having two coupling sections, the first for placing around one of the adjoining undamaged sections of the conduit and the second for allowing the bridging duct to be placed around it by opening the duct along its slit. In this embodiment, each coupler is of unitary construction with a slit along its length and a central rib separating its two coupling sections with a hinge opposite the slit, which allows the coupler to open and close along the slit. 
     In another embodiment, the repair system comprises a bridging duct linking the two sections of the conduit and a pair of couplers having two coupling sections, one mating with its respective section of the conduit and the other mating with the bridging duct. 
     In one method of the present invention, a bridging duct and a pair of couplers are used for repairing a conduit by mating each coupler with a different section of the conduit and mating the bridging duct with each coupler. 
     A conduit repair system is presented. A conduit includes two sections. The conduit repair system comprises a bridging duct linking the two sections of the conduit; and a pair of couplers each having an inner coupling section and an outer coupling section, the pair of couplers each mating with the bridging duct and the two sections of the conduit, the outer coupling section of each pair of the couplers mating with one of the two sections of the conduit and the inner coupling section of each pair of the couplers mating with the bridging duct. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 displays a conduit with a damaged section. 
     FIG. 2 displays the prior art method of repairing a conduit. 
     FIG. 3 a  displays a perspective view of the bridging duct of the present invention. 
     FIG. 3 b  displays an end view of the bridging duct. 
     FIG. 4 a  displays an end view of a clip fastener for sealing the bridging duct. 
     FIG. 4 b  displays a side view of the clip. 
     FIG. 5 a  displays a perspective view of the bridging duct with the clip installed. 
     FIG. 5 b  displays an end view of the bridging duct with the clip installed. 
     FIG. 6 a  displays a side view of the coupler of the invention in which a hinge can be seen for opening and closing the coupler. 
     FIG. 6 b  displays an opposite side view of the coupler. 
     FIG. 6 c  displays an end view of the coupler. 
     FIG. 7 displays the couplers mated with their respective sections of the conduit. 
     FIG. 8 displays the couplers mated with both their respective sections of the conduit and the bridging duct. 
    
    
     DESCRIPTION OF THE INVENTION 
     FIG. 3 a  displays a perspective view of the bridging duct of the present invention. The length and cross-sectional area, normally cylindrical, would ordinarily be proportional to the damaged section of the conduit being replaced or reinforced. Bridging duct  300  includes an opening along its length (e.g. a slit). Along the slit are two opposing walls  302  which extend outward from bridging duct  300 . In the outer surface of each opposing wall  302  is a slot  304 . As will be seen hereinafter, slots  304  are employed for fastening the opposing walls  302  to one another after they have been pressed together to form a tight rigid seal once the bridging duct  300  is in place 
     FIG. 3 b  displays an end view of the bridging duct. In FIG. 3 the opposing walls  302  are shown. In one embodiment of the present invention, the opposing walls extend directly upward from the bridging duct  300 . However, the opposing walls may be angled thereby facilitating the placement of a clip for sealing the opposing walls  302 . A slot  306  is shown in the opposing walls  302 . The slot  306  receives the clip used to seal the opposing walls  302 . Further the slot  306  creates a ridge  305 . The ridge  305  guides a clip and keeps the clip in place during and after sealing of the opposing walls  302 . 
     FIG. 4 a  displays an end view of a clip used in the present invention. FIG. 4 b  displays a side view of the clip used in the present invention. FIG. 4 a  display a clip  400  having legs  402 . The clip  400  is used for insertion in slots  304  which run along the opposing walls  302  of bridging duct  300 . The ridge  305  is used to guide the clip  400  into position. In addition, the ridge  305  serves to constrain the clip  400  so that the clip is removed by sliding the clip on and off the opposing walls  302 ; by positioning the clip at an end of the bridging duct  300  and sliding the clip  400  onto the opposing walls  302 . 
     FIG. 5 a  displays a perspective view of the bridging duct with the clip installed. FIG. 5 b  displays an end view of the bridging duct with the clip installed. In FIGS. 5 a  and  5   b  the clips  400  are shown installed in bridging duct  300 . It should be appreciated that other types of fasteners, such as bolts, could also be used. For additional protection, a vinyl adhesive may be placed along the opposed walls  302 . In addition, a removable film may be used to protect the adhesive. In FIG. 5 b  an end view of the bridging duct  300  is shown with the clip  400  installed. 
     FIG. 6 a  displays a side view of the coupler implemented in accordance with the teachings of the invention, in which a hinge can be seen for opening and closing the coupler. FIG. 6 b  displays an opposite side view of the coupler. FIG. 6 c  displays an end view of the coupler. 
     As shown in FIGS. 6 a ,  6   b , and  6   c , the couplers implemented in accordance with the teachings of the present invention are depicted by reference numeral  600 . Each coupler has two coupling sections  602  and  604 . In one embodiment of the present invention the couplers are implemented as truncated cones. These coupling sections  602  and  604  are separated by a central rib  606 . For the purposes of discussion the coupling sections will be referred to as an inner coupling section  602  and an outer coupling section  604 ; where the inner coupling section  602  mates with the bridging duct and outer coupling section  604  mates with the conduit. As also shown in FIGS. 6 a  and  6   c , rib  606  has a hinge  608  which allows coupler  600  to be rotationally opened and closed along a slit  610  (e.g. shown in FIG. 6 c ) opposite hinge  608 . As will now be described, a bore through coupler  600 , defined by dashed lines  612 , allows coupler  600  to be mated to a section of conduit  100  (e.g. mated with the inner coupling section  602 ) and the bridging duct  300  (e.g. mated with the outer coupling section  604 ). 
     FIG. 7 displays the couplers mated with their respective sections of the conduit. FIG. 7 shows outer coupling section  604  of each coupler  600  mated to a section  202  of conduit  100  by placing it around section  202 . The diameter of the bore  612  through coupler  600  is matched to the diameter of conduit  100  and presses against conduit  100  when the hinge  608  (e.g. of FIG. 6 c ) is used to allow coupler  600  to close along its slit  610  (e.g. of FIG. 6 c ). To ensure a good seal, adhesive can be applied to the periphery of conduit  100  before placing coupler  600  around it. In an alternative embodiment, couplers  600  could be inserted in sections  202  of conduit  100 . 
     In FIG. 7 couplers  600  are shown positioned around conduits  202  and inner conduit  102 . Couplers  600  include two sections, an inner coupling section  602  and an outer coupling section  604 . As shown in FIG. 7, outer coupling section  604  is positioned around the ends of conduit  202 . In addition, inner coupling sections  602  are positioned around inner conduit  102 . Inner coupling section  602  serves as a structural member which mates with the bridging duct shown as  300 . As such, both couplers  600  will reinforce inner conduit  102  and bridging duct  300 . 
     FIG. 8 displays the couplers mated with both their respective sections of the conduit and the bridging duct. As shown in FIG. 8, bridging duct  300  is placed around inner coupling sections  602  of couplers  600 . The opposing walls  302  are sealed using clips  400 ; thereby completing the repair with a rigid, very well sealed assembly. 
     Although the foregoing embodiment employs a coupler  600  of unitary construction, it should be readily apparent that a coupler could be used having two split halves affixed to one another through a locking ring. In addition, the truncated coupling sections could be replaced with cylindrically shaped sections. 
       039  With reference to FIGS. 1-8, during operation two sections of conduit  202  are provided. The two sections of conduit  202  may be from the same conduit or from different conduit. In addition, the method and apparatus of the present invention may be applied to a damaged section of conduit where the damaged section of conduit remains in place and is not removed. As such, the damaged section of conduit would be reinforced by the method and apparatus of the present invention. 
     In one embodiment of the present invention a technician may remove a damaged section of conduit exposing an inner conduit  102 . By removing the damaged section of conduit two sections of conduit  202  (e.g. undamaged sections) are provided for mating and the exposed inner conduit  102  extends between the two sections of conduit. In one embodiment of the present invention, the two sections of conduit  202  are prepared with an adhesive material. 
     Two couplers  600  are then mated to the two sections of conduit  202 . The two couplers  600  include an inner coupling section  602  and an outer coupling section  604  which is separated by a rib  606  which has a hinge  608  on one side and an opening  610  on an oppositely disposed side. The two couplers  600  open and rotate around the hinge  608 . When the two couplers  600  open and rotate around the hinge  608  both the inner coupling section  602  and the outer coupling section  604  open and rotate around the hinge  608 . 
     After the couplers  600  are opened, the outer coupling section  604  is fastened around the section of conduit  202  by closing the coupler  600  around the section of conduit  202  and fastening the couplers  600 . The adhesive material applied to the conduit helps to keep the couplers  600  in place. The couplers  600  are provided with a diameter that produced a tight seal when the couplers  600  are closed around the conduits  202 . 
     Once the couplers  600  are in place a bridging duct  300  is then positioned around the inner coupling sections  602 . The bridging duct  300  is opened along the slit and positioned so that the bridging duct  300  wraps around the inner coupling section  602  and as a result around the conduit  202  and the inner conduit  102 . 
     The opposing walls  302  of the bridging duct  300  are brought together to secure the bridging duct  300  around the couplers  600 . The opposing walls  302  are pressed together and a clip  400  is placed on the opposing walls  302  to form a seal. 
     While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications and embodiments within the scope thereof and additional fields in which the present invention would be of significant utility. 
     It is therefore intended by the appended claims to cover any and all such applications, modifications and embodiments within the scope of the present invention.