Abstract:
An automated vehicle system for laying pipe includes a vehicle (e.g., a stringing trailer) with a bed for storing a plurality of pipes. Tilted gravity members extend across the bed of the vehicle to feed the pipes toward a chute with conveyor running toward the rear of the vehicle. A gate arm and rocker arm mechanism ensure that pipes are fed one at a time onto the conveyor to lay a series of pipes on the ground. Optionally, a joining trailer can be connected behind the vehicle for joining the pipes together before the pipe is placed on the ground.

Description:
CLAIM TO PRIORITY 
     The present continuation application claims priority to and benefit under 35 U.S.C. §120 from pending U.S. patent application Ser. No. 13/645,813, entitled “Automated System for Laying Pipe”, filed on Oct. 5, 2012, all of which is incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates generally to the field of automated systems for laying pipe. More specifically, the present invention discloses an automated vehicle system for laying pipe on the ground or feeding pipe into a joining machine. 
     2. Description of the Related Art 
     The problem with the current process of “stringing” (offloading or laying) the pipe on the ground, and “joining” (connecting the pipe together) in a pipeline is that it is slow, dangerous, costly and sometimes impossible due to weather or terrain. Stringing pipe usually requires one person to drive a truck and two people offloading the pipe from a trailer onto the ground. After the pipe has been offloaded onto the ground, one or more persons must go back and join each pipe together. Workers must push pipe off of a flatbed trailer. Many times work must stop due to adverse weather or difficult terrain. If weather gets too difficult to work in because the trailer cannot maneuver in mud or it becomes too difficult or dangerous for workers to offload pipe in the rain or snow, work must stop. Sometimes terrain gets too steep to where neither the trailer nor the workers can continue working safely and must stop. If the weather or terrain is agreeable and pipe can be offloaded from a trailer successfully it must be picked back up with another crew of workers and moved to join the pipe together or loaded into a machine to be joined together. This process would then involve roughly five workers. 
     SUMMARY OF THE INVENTION 
     In contrast to the prior art, the present invention provides an automated vehicle for laying pipe that requires only one or two workers. In particular, the present invention can be implemented as a string trailer that is towed by a truck or tractor. Optionally, a joining trailer can be connected to the back of the stringing trailer to create a system wherein the pipe can be joined before it touches the ground. The stringing trailer is designed to require only one worker (i.e., the driver), without the assistance of the additional workers on the ground. The driver has the option to feed the pipe into the joining trailer if the joining trailer is connected. If the joining trailer is connected, the pipe can be fed into it and joined together before the pipe exits the rear of the joining trailer and is deposited on the ground. 
     This invention provides an automated vehicle system for laying pipe. The system includes a vehicle (e.g., a stringing trailer) with a bed for storing a plurality of pipes. Tilted gravity members extend across the bed of the vehicle to feed the pipes toward a chute with a conveyor running toward the rear of the vehicle. A gate arm and rocker arm mechanism ensure that pipes are fed one at a time onto the conveyor to lay a series of pipes on the ground. Video is relayed to the driver via closed-circuit television to ensure proper operation of the system. Optionally, a joining trailer can be connected behind the vehicle for joining the pipes together before the pipe is placed on the ground. 
     These and other advantages, features, and objects of the present invention will be more readily understood in view of the following detailed description and the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention can be more readily understood in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a stringing trailer embodying the present invention. 
         FIG. 2  is a side elevational view of the stringing trailer being towed by a truck. 
         FIG. 3  is a detail perspective view of a portion of the pipe-laying mechanism of the stringing trailer. 
         FIG. 4  is a rear view of the stringing trailer. 
         FIG. 5  is a detail view of a portion of one of the upright receivers  10  and pivot plate  12 . 
         FIG. 6  is a detail view of the connection between an upright receiver  10  and a round insert  9 . 
         FIG. 7  is a perspective view of the stringing trailer towing a joining trailer  27 . 
         FIG. 8  is a perspective view of the joining trailer  27 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following is list of the major components of the present invention with their respective reference numbers in the accompanying drawings:
       1 . Fixed upright     2 . Chute arm     3 . Gate arm     4 . Shroud     5 . Support plate     6 . Conveyor belt     7 . Rocker arm     8 . Gravity member     9 . Round insert     10 . Upright receiver     11 . Pivot point     12 . Pivot plate     13 . Base     14 . Receiver slot     15 . Trailer frame     16 . Wheel     17 . Rocker actuator     18 . Base support     19 . Receiver slot handle     20 . Spring     21 . Cable     22 . Chute     23 . Camera     24 . Assembly units     25 . Adjustment pins     26 . Transition cradle     27 . Joining trailer     28 . Doors     29 . Pintle hitch     30 . Sensor     31 . Heater     32 . Air conditioner   

       FIGS. 1 and 2  depict an example of a stringing trailer embodying the present invention. The stringing trailer is made up of a trailer having a number (e.g., four) of modular assembly units  24  that are connected to the frame of the trailer. The first upright is attached to a slide and pin mechanism (similar to a conventional fifth wheel mechanism on a semi-trailer) allowing for travel toward a second upright, thereby allowing shorter length pipe to be used. The assembly units  24  are what hold the pipe and automatically dispense the pipe. Each assembly  24  is made up of a number of other parts which are described below. For the most part, each assembly  24  are essentially the same. The assembly units  24  are equally spaced to hold pipe. The trailer can be made as long or as short as is needed and the assembly units  24  can be spaced between. If a 50 ft. piece of pipe is used, for example, it would be best to have the assembly units  24  spaced so that the two end assembly units  24  are slightly less than 50 ft. apart. The pipe should lay inside the assembly units  24 . 
     The pipe segments are first loaded onto the stringing trailer with a forklift or other device that can lift pipe and set it in between a fixed upright  1  and a round insert  9  that extends upward from an upright receiver  10 , as shown in  FIG. 4 . If such a loading device is used, the stringing trailer should preferably be loaded from the side of the round insert  9 . 
       FIGS. 5 and 6  provide detail views of the round insert  9  and upright receiver  10 . The round insert  9  can slide within the upright receiver  10  between an extended position and a retracted position. The round insert  9  can be lowered into the upright receiver  10  so that when the loading device places the pipe into the stringing trailer it does not drop from a substantial height and damage other parts on the stringing trailer. To lower the round insert  9 , a worker places his hand on the receiver slot handle  19  and pulls down and in, to lock the round insert  9  into its lowered position. A spring  20  biases the round insert  9  upward to enable a worker to easily lift the round insert  9  back up into the extended position after the trailer has been loaded about half way. The remaining pipe can then be loaded with the round insert  9  raised. 
     The upright receiver  10  is welded to a pivot plate  12 . The pivot plate  12  is connected to a pivot point  11  so that if a worker attempting to load the stringing trailer with pipe hits either the round insert  9  or the upright receiver  10 , the metal will not bend or distort. Instead it will pivot about the pivot point  11  which is a pin that runs through the gravity member  8 . The pivot plate  12  is only welded to the upright receiver  10 , but it is not welded to the gravity member  8  or base  13 . It merely slides along the surface of the two to keep the upright receiver  10  and the round insert  9  from moving from side to side. The spring  20  also keeps the upright receiver  10  and the round insert  9  from falling inward toward the center of the trailer. The spring  20  therefore holds a dual purpose of making it easier for a worker to lift the round insert  9  and also keeping the upright receiver  10  from falling inward toward the trailer. It is the cable  21  which makes this possible. The cable  21  is connected with an eyebolt to the base  13  and the bottom of the round insert  9 . When the round insert  9  is in the upright position it pulls the upright receiver  10  down which keeps it in place. 
       FIGS. 3 and 4  illustrate the pipe laying mechanism of the stringing trailer. Any diameter pipe ranging from 4 to 14 in. can be loaded into the stringing trailer as described above. Larger or smaller trailers can be constructed using the present invention for larger or smaller diameter pipe. For example, the entire trailer can be loaded with 6 in. pipe for one load and then 12 in. pipe for another. The trailer cannot be loaded with a mix of different diameter pipe. A few simple adjustments need to be made to the trailer to make it possible to change from one pipe size to another. 
     A gate arm  3  extends laterally inward from the fixed upright  1  of the trailer above the chute and conveyor  6 , as shown in  FIGS. 1 and 4 . The end of the gate arm  3  defines an opening between the gate arm  3  and the gravity member  8  below that allows only one pipe at a time to enter the conveyor  6 . A rocker arm  7  is mounted in this opening to feed a series of pipes (i.e., one at a time) from the bed of the vehicle through the opening and onto the conveyor  6 . 
     To change from one pipe diameter to another, the gate arm  3  can be adjusted up or down and the rocker arm  7  can be adjusted in or out. When the pipe is loaded into the trailer, the tilted gravity members  8  will gravity feed the pipe so that it rolls toward the chute  22 . The gate arm  3  is adjusted to be slightly farther away from the gravity member  8  than the diameter pipe used. For example, if 6 in. outside diameter pipe is used then the opening from the gate arm  3  to the gravity member  8  would need to be about 7 in. If a 12 in. outside diameter pipe is used then the gate arm  3  would need to be about 13 in. away from the gravity member  8 . Thus, the size of the opening defined between the gravity member  8  and gate arm  3  prevents multiple pipes from entering the chute area  22  and rocker arm  7 . In other words, it allows only one pipe at a time to enter the conveyor  6 . 
     The rocker arm  7  is also made from steel or aluminum and can be W-shaped. It is driving by a rocker actuator  17  to pivot back and forth, thereby allowing only one pipe at a time to enter the chute  22  and onto the conveyor belt  6 . Preferably, there are four rocker arms  7 . One is mounted to each of the gravity members  8  that are part of the assembly  24 . They are mounted with a spindle so that they can pivot, thereby allowing one end of the W-shaped rocker arm  7  to rise and then the other in an alternating manner. When one end of each W-shaped rocker arm  7  rises, the other lowers. This allows the rocker arm  7  to stop the next pipe while releasing the one trapped inside the W onto the conveyor belt  6 . The rocker arm  7  is adjustable so that the two ends of the W move closer or farther from the center. This is needed to make it work with different size pipes. The adjustment pins  25  make this possible. The two ends of the rocker arm  7  can be made of square metal tubing that slides over the center portion of the rocker arm  7 . There are holes in both the center portion and the two ends so that a pin can be entered to secure the ends in a particular distance from the center. 
     Preferably, there is one rocker actuator  17  for each rocker arm  7  and all of them function in unison. Each rocker actuator  17  is connected to a central control panel situated on the dash of the truck pulling the stringing trailer. The rocker actuator  17  can be automatically activated by this control panel in the cab of the truck. Once a pipe passes a certain point a sensor  30  triggers the rocker actuator  17  to rotate and the next pipe is loaded onto the conveyor belt  6 . 
     The combination of rocker actuator  17  and rocker arm  7  can be viewed as an actuator mechanism for metering or feeding a series of pipes from the bed of the vehicle through the opening and onto the conveyor  6 , and thereby causing the conveyor  6  to lay a string of pipes behind the vehicle as it travels along the ground. It should also be noted that other means could be used to controlling the rate at which pipe are fed onto the conveyor based on the speed of the vehicle. For example, the actuator mechanism could be controlled by speed data from the vehicle&#39;s speedometer or sensors detecting rotation of the wheels. 
     The conveyor belt  6  is attached using three or four rollers mounted to the base  13 . The conveyor belt  6  is controlled by another sensor that matches the speed of the trailer and the truck pulling the trailer. This way the pipe exits and lands either on the ground, onto stands, or into the joining trailer  27  so that each pipe is dispersed end to end and there are no gaps or overlap between the pipe. Cameras  23  are mounted in a number of locations to assure the pipe is exiting properly and the stringing trailer is working properly as well. It also helps the driver control the stringing trailer from the cab with override buttons if any of the automatic systems is not functioning properly. One is mounted on the fixed upright  1  and the other is mounted on the headache rack of the truck pulling the trailer. 
     When a pipe is exiting the rear of the stringing trailed it is helped onto the ground, in stands, or through an optional joining trailer  27  with the transition cradle  26 . The transition cradle  26  is comprised of steel or aluminum as well, with 4 castor wheels to help guide the pipe while preventing it from being damaged. There may also be a hydraulic cylinder at the base and the side that allows it to be adjusted up and down or left and right. The driver of the truck can see this transition cradle  26  from a digital screen in the cab and can push a button to make it go up and down or left and right accordingly. 
     Optionally, a joining trailer  27  can be used in combination with the stringing trailer as shown in  FIGS. 7 and 8 . The transition cradle  26  guides the pipe into the joining trailer  27 . The pipe enters a set of doors  28  where it then can be joined within the joining trailer  27 . The joining trailer  27  is water tight and is built with either steel or aluminum as well. The joining trailer  27  is temperature controlled with a heater and a cooling unit so that it can join pipe in any weather condition. The joining trailer  27  can be connected to the stringing trailer with a pintle hitch  29 . 
     The following is a discussion of the operational steps in using the present invention. The first step in operating the stringing trailer would be to adjust the gate arm  3  so that it is 1 inch plus the diameter of the pipe away from the gravity member  8  directly below. This prevents more than one pipe from entering the chute  22  at a time. The second step before loading the pipe would be to adjust the rocker arm  7  so that the two ends are the correct distance apart to keep one pipe in position while the other is being released into the chute  22 . Next the round insert  9  should be lowered by grabbing the receiver slot handle  19  and pulling down, thereby locking it into place where the receiver slot  14  is cut out into a J-shape at the bottom. Once the pipe is gently loaded up to the top of the upright receiver  10 , the receiver slot handle  19  can then be raised again and locked into place in the upright position for further loading. The pipe can then continue to be loaded to the top of the round insert  9 . Once the pipe is loaded, the rocker arm  7  can be activated by the driver in the truck cab to allow one of the pipes to roll onto the conveyor belt  6 . The next pipe in line will be stopped by the rocker arm  7 . As the truck and trailer move, the pipe is pushed out the back of the trailer on the conveyor belt  6  at the same speed. As the pipe is exiting the chute  22  it will start to drop at its half-way point due to gravity. The transition cradle  26  can be raised or lowered by the driver in order to help the pipe find the desired path. A shroud  4  is provided at the top of the chute  22  so that if the pipe tips, it will hit the shroud  4  at the top and follow the V-shape of the shroud  4  until it exits the trailer completely. The V-shape of the shroud  4  helps keep the pipe in line as it exits the chute  22 . Once the first pipe reaches a certain point, a sensor  30  actuates the rocker arm  7  automatically and the next pipe drops into place. Alternatively, the rocker arm  7  can be actuated at the driver&#39;s discretion by operation of a joystick, electrical switch, or other manual control. The speed at which the pipe exits the stringing trailer depends on the speed at which the driver is driving because the speed of the conveyor belt  6  is regulated by a signal from a computer in the cab of the truck, or by the driver&#39;s manual control. If, for example, the truck is driving 5 MPH then the pipe will exit the stringing trailer at or around 5 MPH. This process is repeated until all of the pipe has exited the trailer and the driver returns to load more pipe. If there are any problems during the offloading of the pipe, the driver will be able to see because of the cameras  23  mounted on the fixed upright  1  and the headache rack of the truck. 
     The following is a discussion of the steps involved in fabricating the present invention. First, a trailer or other vehicle should be obtained having a bed that is flat for the length of the pipe that is being carried. The fixed upright  1  is then cut and welded to the base  13 . Next, the gravity member  8  with its supports is welded to the base  13 . The round insert  9  is then cut to length, and it would need to be the correct diameter in order to fit snuggly into the upright receiver  10 . The upright receiver  10  is then cut to length, and also the receiver slot  14  is cut into the upright receiver  10 . The top and bottom of the round insert  9  should be welded shut so that the elements would not enter from the top and so that the spring  20  could push against the bottom. A hole is drilled in the bottom plate that was welded onto the round insert  9  so that an eyebolt can be attached and the cable  21  can be attached to the eyebolt. A hole is also drilled into the top of the base  13  directly in the center of where the upright receiver  10  is sitting. This hole, like the one previously mentioned, would be for a second eye bolt and would be used to attach the other end of the cable  21 . The bottom of the upright receiver  10  should be welded shut so that the spring  20  inside could push against it and give the required tension. The pivot plate  12  is then welded to the upright receiver  10  and holes are drilled into it and the gravity member  8  to allow for a spindle to be inserted which would allow it pivot if it were struck by a loader accidentally from the outside. For example, the gravity members  8  can be tilted bars extending across the bed of the vehicle, as shown in  FIGS. 1 and 4 . Each gravity member  8  can be a bar cut at a radius to allow for the travel of the upright receiver  10  and then filled in with steel welded. The portion  2  of the gate arm  3  extending over the chute  22  can be fabricated leaving a hole in the bottom for the swing arm that extends downward from the distal end of the gate arm  3 . 
     The support plates  5  are then welded to the sides of the base  13  and the fixed upright  1 . Each of the conveyor belt castors  6  are then welded to each base. The rocker arm  7  is welded together with steel or aluminum square tube in a W-shape and then fixed to the gravity member  8  with a spindle to allow it to pivot. Once all of the assemblies are welded together they can then be attached to the trailer at equal distances depending on the length of the trailer and the length of the pipe used. Each of these should be supported with a base support  18  which is essentially a triangle welded to both the trailer frame  15  and the assembly  24 . Once all of the assemblies  24  are connected to the trailer frame  15 , the conveyor belt  6  can be attached to the conveyor belt castors  6 . The shroud  4  can also be attached to the chute arm  2  by welding it below. The transition cradle  26  is then fitted with castor wheels and attached to the trailer frame  15  and the assembly with a hinge near the top and a hydraulic cylinder below and to the side. The camera  23  is then attached to the top f the fixed upright  1  and wired to the screen in the cab. The hydraulics are then attached to work the transition cradle  26  and the rocker actuator  17  that rotates the rocker arm  7 . 
     The same result can be reached if this design did not have the pivot plate  12  with the round insert  9 . These added items prevent accidents from occurring and damage to the trailer. The trailer would continue to function without these added features. The trailer will also function without the transition cradle  26  as well. The transition cradle  26  helps with control and prevents wear and tear on the trailer. The big wheels on the trailer set this trailer apart from others because it allows it to function in rough terrain but they would not need to be so big if pipe needed to be laid in a very flat area. 
     The preceding discussion has focused on an embodiment of the present invention as a stringing trailer. It should be understood that the present invention could be installed in the bed of a truck, or moved by a tractor or any other suitable vehicle. Therefore, the term “vehicle” should be broadly construed to cover any of these embodiment of the present invention. 
     The optional joining trailer  27  can be made with steel or aluminum and could use a basic trailer frame with shocks and wheels  16 . The wheels  16  should be off-road and wide like the stringing trailer so that it can function in rough terrain. The box unit on top can be made from fiberglass reinforced with a steel or aluminum frame from inside. A portable heater  31  and air conditioner  32  can be affixed to the ceiling of the joining trailer just as they would on a camper. 
     The above disclosure sets forth a number of embodiments of the present invention described in detail with respect to the accompanying drawings. Those skilled in this art will appreciate that various changes, modifications, other structural arrangements, and other embodiments could be practiced under the teachings of the present invention without departing from the scope of this invention as set forth in the following claims.