Patent Publication Number: US-2013243530-A1

Title: Deep Trench Rod Loader Apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of provisional patent application Ser. No. 61/436,651 filed on Jan. 27, 2011, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the handling of pipe during underground pipe bursting and pipe replacement operations. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a rod handling assembly for use with a rod pushing and pulling machine. The rod handling assembly comprises a rod transfer assembly and a rod transport assembly. The rod transfer assembly comprises a rod receiving member to transport a rod section between, a horizontal receiving position and a rod string axis defined by at least a portion of a rod string. The rod transport assembly is operatively connected to the rod transfer assembly to transport the rod section when not connected to the rod string, between a vertical receiving position and the horizontal receiving position. 
     The present invention is also directed to a rod pushing and pulling machine for use with a rod string comprising a series of rod sections coupled to one another end to end. The rod pushing and pulling machine comprises a housing, a drive system, and a rod handling assembly. The housing includes a front wall having an access opening therein through which the rod string extends from the housing. The drive system is supported by the housing for pushing and pulling the carriage and the rod string along the rod string axis. The rod handling assembly comprises a rod transfer assembly and a rod transport assembly. The rod transfer assembly comprises a rod receiving member to transport one of the series of rod sections between a horizontal receiving position and the rod string axis. The rod transport assembly is operatively connected to the rod transfer assembly to transport the rod section when not connected to the rod string, between a vertical receiving position and the horizontal receiving position. 
     The present invention is further directed to a method for adding rod sections to makeup a rod string comprised of a plurality of rod sections using a rod pushing and pulling machine with a rod string axis and a rod handling assembly. The method comprises the steps of placing a rod section in a vertical receiving position within a rod handling assembly, transporting the rod section from the vertical receiving position to a horizontal receiving position using a rod transport assembly, and axially advancing the rod from a horizontal receiving position to the rod string axis with a rod transfer assembly. 
     The present invention is also directed to a method for removing rod sections to breakup a rod string comprised of a plurality of rod sections, using a pushing and pulling machine with a rod string axis and a rod handling assembly. The method comprises the steps of axially retracting the rod string to position a rod section in a horizontal receiving position, disconnecting the rod section from the rod string, placing an end of the disconnected rod section in a rod transport assembly, activating the rod handling assembly to transport the rod section to a vertical receiving position, and removing the rod section from the rod handling assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a vertical cross-section of a pipe bursting pit containing a rod handling assembly of the present invention connected to a rod pushing and pulling machine. 
         FIG. 2  is a right side view of the rod handling assembly of  FIG. 1  with the rod section a vertical receiving position. 
         FIG. 3  is a side view of the rod handling assembly with the rod section in an intermediate position. 
         FIG. 4  is left side view of the rod handling assembly with the rod section in the horizontal receiving position. 
         FIG. 5  is a top view of the rod handling assembly with the rod section in the horizontal receiving position. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A current method for replacing underground pipes is to use a rod pushing and pulling machine. A rod pushing and pulling machine functions to perform pipe bursting operations to replace the existing pipe without creating an open trench along the entire length of the pipe. Pipe bursting reduces the amount of excavation required to complete the operation as compared to open trench methods; however, a small amount of excavation is still required. There is a strong desire to keep the length and width of the excavation pit minimized, as added width adds to traffic disruption and added length requires more excavation and more restoration expense. Currently, the excavation pit must be large enough to contain a rod box containing a plurality of rod sections, and be large enough for an operator to stand inside in order to feed or remove rods to and from the rod pushing and pulling machine during pipe replacement operations. 
     The present invention solves these problems by utilizing a rod handling assembly  12  to feed rods  30  into the rod pushing and pulling machine  14  as well as remove rods from the rod pushing and pulling machine. The rod handling assembly  12  can attach to the rod pushing and pulling machine  14  and transport rods  30  between a horizontal receiving position to a vertical receiving position. This allows the operator to stand on a platform  16  above the rod pushing and pulling machine  14  in the excavation pit  10  and feed rods  30  into the rod handling assembly  12 , which the rod handling assembly can then feed into the rod pushing and pulling machine. Using the rod handling assembly  12  also allows the rod box  34  to be located on the ground surface  36  outside of the excavation pit  10  as the operator can reach both the rod box and the rod handling assembly by standing on the platform  16 . Placement of the operator  20  above the rod pushing and pulling machine  14  and placement of the rod box  34  outside of the excavation pit  10  greatly reduces the size of the pit and decreases surface disruption. Additionally, safety of the operator is increased. 
     Turning now to the drawings,  FIG. 1  is a cross-sectional view of the pipe bursting pit  10 . A rod handling assembly  12  is shown attached to a rod pushing and pulling machine  14  within pit  10 . A platform  16  may be placed above the rod pushing and pulling machine  14  within the pit  10 . A preferred method of securing the platform  16  within the pit  10  is to attach the platform  16  to the side walls  18  of the pit  10  after the rod pushing and pulling machine  14  has been placed inside the pit. An operator  20  may stand on the platform  16  when operating the rod handling assembly  12 . The operator  20  may operate the rod handling assembly  12  and the rod pushing and pulling machine  14  via the use of a remote control  22 . A receiving antenna  24  mounted on the rod pushing and pulling machine  14  will accept RF signals from the remote control  22 . The signals received by the antennae  24  will actuate the electro hydraulic valves (not shown) to control the rod pushing and pulling machine  14  and the rod handling assembly  12 . In this way, there is no need for an operator  20  to move in the proximity of the pit  10 . 
     Also shown in  FIG. 1  is a rod string  26  extending into a borehole  28 . The rod string  26  is made from a series of rod sections  30  connected together. A rod string axis  32  runs through the center of the rod string  26 . When making the rod string  26 , the operator  20  may grab the rod section  30  from a rod box  34  positioned on a ground surface  36  just outside of the pit  10 . The platform  16  is ideally positioned such that the operator  20  can reach the rod box  34  on the ground surface  36  while standing on the platform. Once the operator  20  selects a rod  30  from the rod box  34  he may place the rod  30  in the rod handling assembly  12  in the vertical receiving position as shown in  FIG. 1 ; the rod handling assembly  12  then transports the rod  30  to the horizontal receiving position (as shown in  FIG. 4 ) at the rod pushing and pulling machine  14 . The rod section  30  is then connected to the rod string  26  using the rod pushing and pulling machine  14  in a process described in published United States Patent application 2007/0245516, the contents of which are incorporated herein by reference. 
     The rod pushing a pulling machine  14  preferably comprises a housing  37  and a drive system (not shown). The housing  37  may include a front wall having an access opening (as seen in the above referenced application) therein through which the rod string  26  extends from the housing. The rod section  30  may be transported into the rod pushing and pulling machine  14  through the access opening. The drive system, as shown in the above referenced application, is used to push and pull the rod string  26  along the rod string axis  32 . 
     Turning now to  FIGS. 2 and 3 ,  FIG. 2  shows the rod handling assembly  12  of  FIG. 1  with the rod in the vertical receiving position and  FIG. 3  shows the rod handling assembly  12  with the rod  30  in an intermediate position. The rod handling assembly  12  comprises a rod transport assembly  38  connected to a rod transfer assembly  40 . The rod transport assembly  38  functions to transport the rod  30  from a vertical receiving position (as shown in  FIG. 2 ) where the rod  30  is within reach of the operator to a horizontal receiving position (as shown in  FIG. 4 ) where the rod  30  is in position to be advanced into the rod pushing and pulling machine  14 . The rod transport assembly  38  is capable of movement in the reverse in order to remove rods  30  from the rod string  26  and the rod pushing and pulling machine  14 . 
     The rod transport assembly  38  comprises a linkage comprising a first and a second mounting brace  41   a  and  41   b , a first and second arm  42   a  and  42   b , a first and second pivot link  44   a  and  44   b , a top arm  46 , a top and bottom pivot pin  48   a  and  48   b , a socket  50 , and a cylinder  52 . 
     The first mounting brace  41   a  connects to the first link arm  42   a  at a pivot point  54   a . The second mounting brace  41   b  connects to the second arm  42   b  at pivot point  54   b . The first and second mounting braces  41   a  and  41   b  are connected to the rod transfer assembly  40  at a mounting plate  72 . The first and second mounting braces  41   a  and  41   b  remain in a stationary and vertical position during operation. A mounting brace connector  56  connects each top edge of the first and second mounting brace  41   a  and  41   b  to provide stability. The first and second arms  42   a  and  42   b  form a substantially triangular shape and move from a vertical to horizontal position during operation. The first arm  42   a  connects to the first pivot link  44   a  at the end of arm  42   a  opposite connection point  54   a  at a pivot point  58   a . The second arm  42   b  connects to the second pivot link  44   b  also at the end of arm  42   b  opposite connection point  54   b  at a pivot point  58   b . The first pivot link  44   a  is shorter in length than the first and second arms  42   a  and  42   b  and functions to allow socket  50  to pivot during operation of the assembly  38 . The second pivot link  44   b  extends out past the edge of the second arm  42   b . The first and second pivot links  44   a  and  44   b  connect to the top link arm  46  at pivot points  60 . The top arm  46  forms an elongate arm connected to the first mounting brace  41   a  at one end at a pivot point  62   a  and connects to the second mounting brace  41   b  at the opposite end at a pivot point  62   b.    
     Continuing with  FIGS. 2 and 3 , the cylinder  52  connects to the first and second mounting brace  41   a  and  41   b  at pivot point  64 . The opposite end of the cylinder  52  connects to the first and second arms  42   a  and  42   b  at pivot point  66 . 
     In operation the cylinder  52  extends and pushes the first and second arms  42   a  and  42   b  downward. Movement of the first and second arms  42   a  and  42   b  causes movement of the first and second pivot links  44   a  and  44   b  and the top arm  46  and movement of the socket  50  to the horizontal receiving position. 
     The socket  50  attaches to the edges of the second pivot link  44   b  via pins  68   a  and  68   b . Running lengthwise between pin  68   a  and pivot points  60  is pivot arm  48   a . Similarly, running lengthwise between pin  68   b  and pivot points  58  is pivot arm  48   b . Activation of the arms  42   a  and  42   b , middle links  44   a  and  44   b , and top arm  46  causes the pivot arms  48   a  and  48   b  to rotate at pivot points  60  and  58 . In operation, extension of the cylinder  52  causes the first and second arms  42   a  and  42   b  to rotate downwards from a vertical to horizontal position pulling the first and second pivot link  44   a  and  44   b  and the top  46  downwards causing the socket  50  to rotate in the direction of arrow  70  via the rotation of pivot arms  48   a  and  48   b.    
       FIGS. 2 and 3  also show the rod transfer assembly  40 . The rod transfer assembly  40  supports the rod transport assembly  38  and functions to transfer the rod  30 , when in the horizontal receiving position (as shown in  FIG. 4 ), to and from the rod pushing and pulling machine  14 . The rod transfer assembly  40  comprises mounting plate  72 , a frame  74 , a rod receiving member  76 , a cylinder  78 , and a frame arm  80 . The mounting plate  72  forms a substantially rectangular shape and is configured for mounting onto the rod pushing and pulling machine  14 . The first and second mounting brace  41   a  and  41   b  connect to the mounting plate  72  adjacent the frame  74 . The mounting plate  72  comprises an opening  82  to allow movement of the rod  30  between the vertical receiving position and the horizontal receiving position without threading the rod  30  through the mounting plate  72 . 
     The frame  74  comprises a pair of guide arms  84   a  and  84   b  and a connector  86 . The guide arms  84   a  and  84   b  attach to the mounting plate  72  and are connected opposite the mounting plate  72  via connector  86 . The rod receiving member  76  comprises a pair of jaws  88 , a cylinder  90 , and a brace  92 . The rod receiving member  76  is open on one side and configured for receiving and gripping the rod  30  in the horizontal receiving position without threading. The pair of jaws  88  of the rod receiving member  76  work to grip the rod  30  upon being actuated by the cylinder  90 . 
     The rod receiving member  76  shown in  FIGS. 2 and 3  is movable axially about the guide arms  84   a  and  84   b  of the frame  74 . The rod receiving member  76  is capable of moving between mounting plate  72  and link  86 . The cylinder  78  of the rod transfer assembly  40  comprises a rod  94 . The rod attaches to the brace  92  of the rod receiving member  76  via a pin  96 . The cylinder  78  functions to move the rod receiving member  76  axially between the mounting plate  72  and the link  86  of the frame  74 . When the rod  30  is in the horizontal receiving position and gripped by the pair of jaws  88  of the rod receiving member  76 , movement of the rod receiving member  76  axially by extension and retraction of the rod  94  within the cylinder  78  moves the rod  30  to and from the horizontal receiving position and the rod string axis  32  (as shown in  FIG. 1 ). The cylinder  78  connects to the frame arm  80  via a pin  98 . The frame arm  80  is configured for mounting onto the rod pushing and pulling device  14  to help support the cylinder  78 . 
     Turning now to  FIG. 4 , the rod handling assembly  12  is shown with the rod  30  in the horizontal receiving position within the rod receiving member  76  comprising the pair of jaws  88 . The rod transport assembly  38  is shown in a horizontal position with the cylinder  52  all the way extended pushing down on the first and second link arms  42   a  and  42   b . The movement of first and second arms  42   a  and  42   b  down pulls first and second pivot link  44   a  and  44   b  as well as top arm  46  down. This downward movement causes pivot arms  48   a  and  48   b  to rotate and in turn rotates the socket  50  in the direction of arrow  70  (shown in  FIG. 2 ). The rotation of the socket  50  causes the rod  30  to rotate from a vertical receiving position (as shown in  FIG. 2 ) to a horizontal receiving position (as shown in  FIG. 4 ) while at the same time being pulled downwards and placed into the rod receiving member  76 . 
     Continuing with  FIG. 4 , in operation, the rod  30  passes through opening  82  on the mounting plate  72  and is placed within the rod receiving member  76  without threading the rod  30  through the mounting plate  72 .  FIG. 4  shows the rod receiving member  76  at the back of frame  74  near connector  86  due to cylinder rod  94  being fully extended from the cylinder  78 . In this position the rod  30  has not yet been axially advanced to rod pushing and pulling machine  14  in order to be connected to the rod string  26  along the rod string axis  32  (as shown in  FIG. 5 ). 
     Turning to  FIG. 5 , a top view of the rod handling assembly  12  is shown with the rod  30  positioned at the rod string axis  32 . The cylinder  78  is shown in the retracted position wherein the rod receiving member  76  has been axially advanced proximate the mounting plate  72 . The pair of jaws  88  are shown gripping the rod  30 . Movement of the rod receiving member  76  towards the mounting plate  72  pulls the rod  30  from the socket  50 . Once pulled from the socket  50 , the rod  30  is axially advanced to the rod pushing and pulling machine  14  (as shown in  FIG. 1 ) along the rod string axis  32  in preparation for being added to the rod string  26  via the rod pushing and pulling machine  14 . First and second arms  42   a  and  42   b , first and second pivot links  44   a  and  44   b , and top arm  46  are shown pushed downwards in a generally horizontal position in  FIG. 5 . 
     In a method of adding rod sections to makeup the rod string, the operator  20  selects a rod  30  from the rod box  34 . The operator  20  then places the rod  30  within the socket  50  of the rod transport assembly  38 ; the rod transport assembly  38  holding the rod in the vertical receiving position. The cylinder  52  of the rod transport assembly  38  extends pushing the first and second arm  42   a  and  42   b  downwards and causes pivot arms  48   a  and  48   b  to descend and rotate socket  50 . The rod section  30  is simultaneously moved downwards and rotated through opening  82  in mounting plate  72  to a horizontal receiving position and placed into the rod receiving member  76 . The jaws  88  then grip the rod  30  by the activation of cylinder  90 . Cylinder  78  of the rod transfer assembly  40  then retracts pulling the rod receiving member  76  axially towards mounting frame  72  and closer to the rod pushing and pulling machine  14 . This action pulls the rod  30  from the socket  50  and puts the rod  30  in position to be accepted by the rod pushing and pulling machine  14  and connected to the rod string  26  along the rod string axis  32 . After the rod  30  is engaged by the rod pushing and pulling machine  14 , the cylinder  52  retracts pulling the first and second arms  42   a  and  42   b  upwards causing the first and second pivot links  44   a  and  44   b  and the top arm  46  to return to their vertical receiving position. The rod receiving member  76  is retracted axially backwards via extension of rod  94  and prepared for receiving another rod  30 . These steps are repeated until the rod string  26  has been completed. 
     In a method for removing rod sections  30  to breakup the rod string  26 , the rod  30  is first disconnected from the rod string  26  via the rod pushing and pulling machine  14 . The rod receiving member  76  is axially advanced toward the mounting plate  72 , placing it in position for receiving the rod  30  from the rod pushing and pulling machine  14 . The rod receiving member  76  grips onto the rod  30  via the jaws  88  and retracts axially backwards by extension of cylinder  78 . Extension of cylinder  78  places the rod  30  within socket  50 . Once the rod  30  is within socket  50 , the jaws  88  release the rod  30 . The cylinder  52  of the rod transport assembly  38  then retracts pulling the first and second arms  42   a  and  42   b  upwards which causes the pivot arms  48   a  and  48   b  to pivot rotating the socket  50  and rod  30  upwards to a vertical receiving position. Once the socket  50  and the rod  30  are in the vertical receiving position, the operator  20  may remove the rod  30  from the socket  50  and place the rod back in the rod box  34 . The rod transport assembly  38  then returns to the horizontal receiving position and the rod receiving member  76  advances axially forward in preparation for receiving another rod  30  from the rod pushing and pulling machine  14 . These steps are repeated until the rod string  26  has been completely disassembled and removed from the borehole  28 . 
     Although the present invention has been described with respect to several specific preferred embodiments thereof, various changes and modifications may be suggested to one skilled in the art, and it is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims.