Abstract:
A conduit breach location detector for detecting leaks in a conduit is disclosed. The conduit breach location detector includes a shuttle cage for connection to the conduit. A sounding shuttle is provided in the shuttle cage. A sounding cable may be connected to the sounding shuttle. A pressurization system is connected to the shuttle cage for pressurizing the shuttle cage and pushing the sounding shuttle through the conduit.

Description:
FIELD OF THE INVENTION 
   The present invention relates to devices for detecting breaches in conduits. More particularly, the present invention relates to a conduit breach location detector which is suitable for detecting the location of a breach in a pipe or other conduit. 
   BACKGROUND OF THE INVENTION 
   Over time, underground utility conduits frequently develop leaks which cause water or gas to leak from the conduit. However, it is often difficult for repair personnel to determine the precise location of a breach in a conduit such that the conduit can be repaired in a timely and efficient manner. Therefore, what is needed is a conduit breach location detector which is capable of detecting the location of a breach in a conduit to facilitate expeditious and efficient repair or replacement of the conduit. 
   SUMMARY OF THE INVENTION 
   A conduit breach location detector for detecting leaks in a conduit is disclosed. The conduit breach location detector includes a shuttle cage for connection to the conduit. A shuttle is provided in the shuttle cage. A cable may be connected to the shuttle. A pressurization system is connected to the shuttle cage for pressurizing the shuttle cage and pushing the shuttle through the conduit. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: 
       FIG. 1  is a cross-sectional view of an illustrative embodiment of the conduit breach location detector according to the present invention; 
       FIG. 2  is a longitudinal sectional view of a segment of a conduit, more particularly illustrating advancement of a shuttle element of the conduit breach location detector through the conduit as the shuttle approaches a breach in the conduit; and 
       FIG. 3  is a cross-sectional view of a shuttle according to an alternative embodiment of the conduit breach location detector. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring initially to  FIGS. 1 and 2  of the drawings, an illustrative embodiment of the conduit breach location detector, hereinafter detector, according to the present invention is generally indicated by reference numeral  1 . As shown in  FIG. 1 , the detector  1  includes a shuttle  2 . The shuttle  2  includes a shuttle housing  3  which may have a generally elongated, cylindrical configuration and includes a housing interior  4 . A housing tip  5 , which may have a tapered shape, as shown, terminates the front end of the shuttle housing  3 . 
   Multiple fins extend from the shuttle housing  3 . For example, multiple front fins  6  may extend from the shuttle housing  3 , adjacent to the housing tip  5 , and multiple rear fins  7  may extend from the shuttle housing  3 , adjacent to the rear end of the shuttle housing  3 . The front fins  6  and rear fins  7  may be pivotally attached to the shuttle housing  3 . 
   A cable  14 , which may be dispensed from a wound cable reel  15 , is attached to the shuttle  2 , using any of a variety of techniques known to those skilled in the art. For example, an elongated attachment rod  10  may extend from the housing tip  5 , rearwardly through the housing interior  4 , as shown. An attachment eye  11  is provided on the attachment rod  10 , and a shuttle attachment hook  16  provided on the end of the cable  14  engages the attachment eye  11 . 
   The shuttle  2  may be used in conjunction with a shuttle cage  20 , as will be hereinafter further described. The shuttle cage  20  typically includes an elongated, generally cylindrical cage housing  21  having a cage housing interior  22 . Interior housing threads  21   a  may be provided at the front and rear ends of the cage housing  21 . A rear compression fitting  23  is removably fitted in the rear end of the cage housing  21 . Accordingly, the rear compression fitting  23  may be provided with exterior housing threads  23   b  which threadibly engage the interior housing threads  21   a  of the cage housing  21 . A nipple  24 , having exterior nipple threads  25 , extends from the rear compression fitting  23 . A cable opening  23   a  extends through the rear compression fitting  23  and nipple  24 . Therefore, the cable  14  extends from the cable reel  15 , through the cable opening  23   a  and into the cage housing interior  22 , where the cable  14  attaches to the shuttle  2 . A nut  27  typically threadibly engages the nipple threads  25  on the nipple  24 , and an O-ring  26  provides an airtight seal between the nut  27  and the cable  14 . 
   A front compression fitting  30  is provided on the front end of the cage housing  21 . Accordingly, fitting threads  31  are typically provided on the exterior of the front compression fitting  30  for engaging the interior housing threads  21   a  at the front end of the cage housing  21 . A fitting opening  32  extends through the front compression fitting  30  and communicates with the cage housing interior  22 . The front compression fitting  30  is further provided with interior or exterior threads (not shown) which are adapted to engage conduit threads (not shown) provided on a conduit  46  ( FIG. 2 ) having a breach  48  in typical use of the detector  1 , as will be hereinafter described. 
   As further shown in  FIG. 1 , a pressurization system  34  is provided on the shuttle cage  20 . The pressurization system  34  includes a rear inlet conduit  35  and a front inlet conduit  36  which are provided in fluid communication with the cage housing interior  22 . A connecting conduit  37  establishes fluid communication between the rear inlet conduit  35  and the front inlet conduit  36 . A rear pressure gauge  38  and a front pressure gauge  39  are provided in fluid communication with the rear inlet conduit  35  and the front inlet conduit  36 , respectively. A rear valve  40  and a front valve  41  are provided in the connecting conduit  37 , in spaced-apart relationship to each other. An inlet nipple  42  is provided in fluid communication with the connecting conduit  37 , between the rear valve  40  and the front valve  41 . 
   In typical operation of the invention, the detector  1  is used to determine the location of a breach  48  in a conduit  46 , such as a water or gas utility conduit, for example, as shown in  FIG. 2 . Accordingly, the front compression fitting  30  of the shuttle cage  20  is initially connected to the end (not shown) of the conduit  46 , which has generally the same diameter as the diameter of the cage housing  21 . The shuttle  2  is positioned in the cage housing interior  22  of the cage housing  21  such that the rear fins  7  of the shuttle  2  are positioned forwardly of the rear inlet conduit  35  of the pressurization system  34 . An air or water supply (not shown) is connected to the inlet nipple  42  of the pressurization system  34 . Next, the rear valve  40  is closed and the front valve  41  is opened. Air or water (not shown) is introduced into the cage housing interior  22  through the inlet nipple  42 , the connecting conduit  37  and the front inlet conduit  36 , respectively. After pressure in the conduit interior  47  of the conduit  46  equalizes with that in the cage housing interior  22 , the pressure on the front pressure gauge  39  is noted. The front valve  41  is then closed and the rear valve  40  is opened, thereby facilitating the flow of air or water into the cage housing interior  22  through the rear inlet conduit  35 . Consequently, the air or water pressure behind the shuttle  2  pushes against the front fins  6  and the rear fins  7 , thereby expanding or pivoting the front fins  6  and rear fins  7  outwardly and advancing the shuttle  2  forwardly from the cage housing interior  22 , through the fitting opening  22  of the front compression fitting  30  and into the conduit interior  47  of the conduit  46 , respectively. The pressure in the cage housing interior  22  is regulated such that the reading on the rear pressure gauge  38  matches the pressure reading which was initially noted on the front pressure gauge  39 . 
   As it advances through the conduit interior  47  of the conduit  46 , the shuttle  2  approaches a breach  48  in the conduit  46 . As the rear fin  7  of the shuttle  2  passes the breach  48 , the pressure in the conduit interior  47  drops since the air or gas exits the conduit interior  47  through the breach  48 . Consequently, the shuttle  2  stops in the conduit interior  47 , just beyond the breach  48 . The drop in pressure in the conduit interior  47  registers on the rear gauge  38 . The location of the breach  48  in the conduit  46  is noted by noting the length of cable  14  which was drawn from the cable reel  15  by the shuttle  2 . Therefore, the distance of the conduit breach  48  from the end of the conduit  46  to which the shuttle cage  20  is attached corresponds to the length of the cable  14  which was drawn from the cable reel  15  and into the conduit interior  47 . This allows personnel to repair the conduit  46 . 
   Referring next to  FIG. 3 , in an alternative embodiment of the conduit breach location detector, generally indicated by reference numeral  1   a , a rod attachment wall  8  spans the housing interior  4 . A battery compartment  9  is provided forwardly of the housing interior  4  in the shuttle housing  3 . The attachment rod  10  extends rearwardly from the rod attachment wall  8 . A transmitter  12  is provided in the housing tip  5 , and batteries  9   a  are provided in the battery compartment  9 . Accordingly, the location of the shuttle  2  in the conduit interior  47  of the conduit  46  is monitored by the transmission of electromagnetic signals from the transmitter  12  to a receiver (not shown) provided at the entry of the conduit  46  rather than by noting the length of cable  14  which is drawn into the conduit interior  47 . It is to be understood that the cable  14  may optionally be omitted from the shuttle  2  of the detector  1   a  as a technique to measure the location of the conduit breach  48  from the end of the conduit  46 . 
   While the preferred embodiments of the invention have been described above, it will be recognized and understood that various modifications can be made in the invention and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.