Abstract:
A method of providing operating electrical power from a stationary power source to a mobile conveyor utilized in material handling at a mine site as the conveyor moves over a predetermined path at the site without having to move long lengths of cable as the conveyor moves away from the power source. The method utilizes a cable reel that features a power receptacle into which a cable connector can be easily plugged and unplugged.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Application No. 61/580,748, filed Dec. 28, 2011. 
     
    
     FIELD OF INVENTION 
       [0002]    The present invention relates to material handling and, more particularly, relates to apparatuses and methods for stacking material such as ores, minerals or agglomerated material at mine sites. In more particularity, this invention relates to a method of powering large mobile equipment such as very large and slow moving equipment used in such applications. 
         [0003]    BACKGROUND AND DESCRIPTION OF THE PRIOR ART 
         [0004]    Conveyors may be used in stackers to stack material or in devices configured to reclaim material from a stack. Typically, systems designed for stacking and reclaiming material utilize a number of conveyors. One set of conveyors is typically used to convey material to a stacker for stacking in a particular area. Another set of conveyors is used to reclaim the material stacked in that area. Examples of systems used to stack material or reclaim material are disclosed in U.S. Pat. Nos. 7,191,888, 6,782,993, 6,085,890, 5,609,397, 5,562,194, 5,090,549, 4,139,087, 3,604,757, 2,851,150 and 1,996,488. 
         [0005]    Conveyor systems used to stack material or reclaim material often include a system of conveying devices. For example, overland conveyors are often used to transport material over relatively long distances to different locations. An overland stacking conveyor may be configured to move material from a material receiving location to a storage pile. An overland reclaiming conveyor may be configured to convey material from a storage area to an area designated for using the material. Typically, a mobile bridge conveyor or other conveyor is positioned adjacent to a stacking overland conveyor. An overland tripper may be configured to feed material from an overland conveyor to a mobile bridge conveyor. A mobile overland tripper straddles the overland and typically travels a long distance (e.g. 2000 m or more). The mobile overland tripper may feed material from a stacking overland conveyor onto a mobile stacking and reclaiming apparatus for stacking the material. 
         [0006]    The tripper is powered electrically and often supplies power to downstream equipment, thus requiring multiple cables and power connections. It is impractical for mobile trippers to carry the entire amount of power cable needed to travel over such distances, as the size of cable reel required can become impractically large for very long cables. Although a cable drum can hold significantly more cable than a cable reel, its use adds substantially more length and cost to the tripper conveyor compared to a cable reel. In addition, weight is an issue for trippers, which can weigh 200,000 pounds or more. 
         [0007]    The power cable used for tripper conveyors is comparatively thick (˜2½-3″ diameter) and heavy (˜1000 kg/100 m). Therefore, to conserve both space and weight on the tripper, tripper conveyors will typically carry about 100-400 m of cable on a reel, which will be not nearly as long as the path that the tripper has to traverse, which can often be in excess of 2000 m. Therefore, it will be necessary during the operation of the tripper to move the cable carried by the tripper from power outlet to power outlet. If the tripper carries, as an example, 200 m of cable, it will be necessary to move over 2000 kg of bulky, hard to maneuver cable to the next power outlet. Reattaching and attaching the cable to another position along the tripper&#39;s path can easily take half a day, with it being necessary to put the cable on a pallet or dolly drag it to the next outlet. Such a procedure is very manpower intensive, and increases the risk of potential back injury to personnel handling the cable. 
         [0008]    Therefore it would be advantageous, and it is an object of this invention, to have a method of reattaching and attaching a power cable used to electrically power large mobile conveyors for the distance of the path the tripper takes while in operation. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention provides a method of supplying operating electrical power from a stationary power source to a mobile conveyor utilized in material handling at a mine site as the conveyor moves over a predetermined path at the site without having to move long lengths of cable as the conveyor moves away from the power source. The method utilizes a cable reel that features a power receptacle into which a cable connector can be easily plugged and unplugged. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIGS. 1-8  show a prior art method of powering a mobile conveyor using electrical cable. 
           [0011]      FIGS. 9-19  sequentially set forth one embodiment of the present invention&#39;s method of powering a mobile conveyor. 
           [0012]      FIG. 20  is a side view of the novel cable reel of the present invention. 
           [0013]      FIG. 21  is an elevation view of the cable reel of the present invention. 
           [0014]      FIG. 22  is an elevation view of the cable reel including the diverter showing removable parts. 
           [0015]      FIG. 23  depicts the flipover including a removable cover plate. 
           [0016]      FIG. 24-26  sequentially depicts the use of a flipover in conjunction with the movement of the cable reel. 
           [0017]      FIG. 27-34  sequentially set forth another embodiment of the present invention&#39;s method of powdering a mobile conveyor in which two cable reels are employed. 
           [0018]      FIG. 35  depicts a plan view of the two reel embodiment. 
           [0019]      FIG. 36  depicts an elevation view of the two reel embodiment. 
       
    
    
       [0020]    The figures are not necessarily drawn to scale. 
       DESCRIPTION OF THE INVENTION 
       [0021]      FIG. 1  depicts a prior art layout of cables prior to the movement of the mobile conveyor. Individual cables  101 ,  102  and  103 , each  400   m  in length, are laid out in combination parallel to the path that the conveyor will move, which is in the direction of arrow A. Cable  101  has on one end  101   a,  which in the depicted view is the left end, an electrical connector or plug (not shown) that is wired into the electric house  104  which provides electrical power to the cable. On cable  101 &#39;s other, i.e. right, end there is electrical plug  101   b.  Cables  102  and  103  each have an electrical plug, respectively  102   a  and  103   a  on each cable&#39;s left end that is located closer to electric house  104  and a plug, respectively  102   b  and  103   b,  on each cable&#39;s opposite, i.e. right, end that is located further from electric house  104 . 
         [0022]      FIG. 2  is the first in a sequence showing the procedure, according to one prior art method, for powering a mobile conveyor as it traverses a path in a mining environment in the direction of arrow A. Reel  105 , from which cable  106  has been unwound, is fixedly mounted on a mobile conveyor  108 . In the position depicted in  FIG. 2 , the mobile conveyor has advanced approximately half the distance of cable  101 , i.e. approximately 200 yards in the direction of arrow A. Cable  106  has been unwound to its complete length and has an electrical plug  106   a  on one end, with a plug on its other end  106   b  being hard wired into the junction box (not shown) proximate to the reel. Plug  106   a  is connected to plug  101   b  of cable  101  to thereby provide power from the electric house  104  to the mobile conveyor  108 . 
         [0023]      FIG. 3  depicts reel  105  having drawn up essentially all of cable  106  while the mobile conveyor  108  moved approximately 200 m in the direction of arrow A. Mobile conveyor  108  still maintains electrical connection with electric house  104 . 
         [0024]    In  FIG. 4 , the mobile conveyor  108  has moved another  200  m in the direction of arrow A, in the process unwinding essentially all of cable  106  from reel  105 . With the cable having been completely drawn out from reel  105 , mobile conveyor cannot to move any further in the direction of arrow A and still maintain an electrical connection with electric house  104 . The relocation of cable  106  is now required. 
         [0025]    In  FIG. 5  the path the relocation of cable  106  will take, as represented by dotted line  107 , is depicted. Plug  106   a  must be disconnected from plug  101   b  and the cable is moved over 400 meters after which plug  101   b  is connected to the male plug  102   b  at the far right end of cable  102 , that is, the end of cable  102  furthest from the electric house  104 . This requires moving cable weighing over 2000 kg 400 meters in a matter that will not unduly stress the cable. 
         [0026]    In  FIG. 6  the movement of the cable has been completed. Furthermore, plug  106   a  is connected with plug  102   b  and plug  101   b  is connected to plug  102   a  to complete the connection of electric house  104  to reel  105 . 
         [0027]    In  FIG. 7  cable  106  is drawn up by reel  105  as the mobile conveyor has moved another 200 meters in the direction of Arrow A to be roughly aligned with the right end of cable  102 . 
         [0028]    In  FIG. 8  the mobile conveyor  108  has moved another 200 meters to the right in the direction of arrow A and the cable has been drawn out from reel  105 . For the mobile conveyor to continue to move in the direction of arrow A cable  106  must be again moved in the manner depicted in  FIG. 5 , that is cable  106 &#39;s plug  106   a  must be disconnected from plug  102   b,  moved 400 meters in the direction of Arrow A, and connected to plug  103   b.  To complete the connection to reel  105 , plug  102   b  is connected to plug  103   a.    
         [0029]      FIGS. 9-19  depict one embodiment of the present invention for powering a mobile conveyor such as a mobile tripper  208 . 
         [0030]    As shown in  FIG. 9 , the cables  201 - 204  (also referred to as, respectively, the first, second, third and fourth laid out cables) are laid out in a manner roughly adjacent to and in combination approximately parallel to the mobile conveyor&#39;s predetermined path. The cables however are not laid out end to end in the manner shown in  FIG. 1 , but are folded back upon themselves, approximately in the form of a thin letter “V”, so that when so laid out the ends of each cable, and therefore the plugs located at the ends ( 201   a  and b,  202   a  and  202   b  and so on), are placed proximate to each other and are located nearer to a stationary power source, i.e. electrical house  214 , than the foldover points (also referred to as the “fold”) in each cable at the base or point of the “V”, represented as  201   c,    202   c,    203   c  and  204   c.  As depicted, the cables are  400   m  in length, although it is understood that this is not a required length of the cables, and the length can vary depending upon the requirements of the practitioner. Another feature of the present invention is that reel  215  is constructed with a plug that is adaptable to be wired into an adjacent junction box on the conveyor, which plug is designed to be easily and quickly connected to and disconnected from a plug from a power cable. Thus, a cable delivering power to the reel from a power source removed from the conveyor does not have to be hard wired into the junction box. Thus, as depicted in  FIG. 9 , plug  201   b  is connected to the electric house and its opposite plug  201   a  is connected to a mating plug (not shown in the Figure) on reel  215 . It is one of the advantages of this embodiment of the present invention that a dedicated cable (in the manner of cable  106  as seen in  FIGS. 1-8 ) is not needed for reel  215 . Therefore, when reel  215  is electrically connected to a junction box located on mobile conveyor  208 , and cable  201  is used to supply power from electrical house  214  to reel  215 , mobile conveyor  208  will be supplied with electrical power. 
         [0031]    With reference to  FIG. 10 , as the mobile conveyor  208  moves in the direction of arrow A, and toward fold  201   c,  reel  215  picks or spools up cable  201  until the reel is full when conveyor  208  comes up adjacent to fold  201   c.  At this point the cable, which was folded back upon itself when initially laid out, is easily flipped over at point  201   c  in the manner described herein. Reel  215  will commence to unwind cable  201  as the conveyor moves in the direction of arrow A toward cable  202 . 
         [0032]      FIG. 11  shows conveyor  208  having advanced another  200  meters, that is, with essentially the entire length of cable  201  having spooled out and the reel being substantially empty of cable. 
         [0033]    In  FIG. 12 , plug  201   a  is disconnected from reel  215  and connected with plug  202   b  of cable  202 . As depicted line  202  is live, but no power is depicted going to conveyor  208 . 
         [0034]    In  FIG. 13 , plug  202   a  is connected to reel  215 , with conveyor  208  therefore becoming live. It is seen that by utilizing the present method there is much less cable handling and moving than in prior art systems, as moving the cable over long distances is not required. 
         [0035]    This sequence will be repeated for each of cables  203  and  204  as mobile conveyor  208  continues to move in the direction of arrow A.  FIG. 14  shows the mobile conveyor at the end of the run in the direction of arrow A with plug  204   a  being connected into the conveyor and all of the cables being live. 
         [0036]    In  FIG. 15  conveyor  208  now begins to move on its reverse path in the direction of arrow B. Reel  105  has drawn up its maximum capacity of cable  204 . 
         [0037]    In  FIG. 16  cable  204  has been substantially unreeled is folded back upon itself at point  204   c  as the reel continues to move from right to left in the direction of arrow B. 
         [0038]    In  FIG. 17  plug  204   a  is disconnected from reel  215 . Mobile conveyor  208  is therefore without power. 
         [0039]    In  FIG. 18  plug  204   b  has been disconnected from female plug  204   a,  Cable  204  is therefore no longer live, and is now folded back upon itself and is in the initial position depicted in  FIG. 9 . Plug  203   a  has been connected to reel  215 , thus reestablishing power to reel  215  and therefore the mobile conveyor. 
         [0040]    This sequence is repeated as the mobile conveyor continues to retrace its path in the direction of arrow B.  FIG. 19  shows the conveyor at the far left of its run, where it is in the same position as it was in  FIG. 9 . The sequence as shown can be repeated indefinitely, if desired. 
         [0041]      FIGS. 20-21  depict the cable reel  400  advantageously used in the present invention. One unique feature of cable reel  400  is plug  401  which is wired into the reel and which permits a mating plug  402  on one end of a power cable, such as cable  403  in the Figure, to be quickly connected and disconnected. Reel  400  further comprises cable reel drive unit  404 . Cable diverter  406  is associated with and is proximate to the reel, and aids in directing the power cable utilized in conjunction with the reel, particularly at the foldover points. Cable diverter  406  has cover  411 , with diverter  406  being mounted on machine frame  405 . Cable reel  400  further has section  410 , which is also depicted in  FIG. 22 , which is removable as shown by arrow D to permit a power cable to have access to the interior of the reel. 
         [0042]      FIG. 22  shows the reel section  410  which is removable as per arrow D, diverter cover plate  411 , removable as per arrow F, which together allow the cable  403 , with plug  402  attached to it, to be conveniently removed as per arrows E and to thereafter permit the rapid installation of the next cable in the series. 
         [0043]      FIG. 23  illustrates flipover  420 , including a removable cover plate  421 , on the flipover to allow convenient installation/removal of the cable in the flipover. The flipover is optionally utilized at a foldover point in the cable, i.e.  201   c,    202   c  etc. It&#39;s advantageous to have a flipover at that point when the cable begins to loop back in the opposite direction when the conveyor passes by. When the cable begins to fold back on itself—that is, from the V position to a straight cable or vice versa, a flipover is employed to support the cable so it doesn&#39;t fold too severely back on itself so when conveyor passes over at that point and sweeps along the cable the cable won&#39;t become damaged from too much stress. On the mobile conveyor&#39;s return run the flipover will reverse the process and begin turning the cable over on itself. 
         [0044]    The use of a flipover is further illustrated in  FIGS. 24-26 .  FIG. 24  shows the cable reel  400  and mobile conveyor  430  on the left side of flipover  420  while moving in the direction of 
         [0045]    Arrow A. In the case where the mobile conveyor  430  is traveling toward the flipover  420 , the cable reel  400  is rotating counterclockwise and reeling in the cable. Flipover  420  is configured in part with a left semicircle  422  and a right semicircle  423 , both adaptable to receive cable  403 . Diverter  406  diverts the cable  403  to the right in the direction of flipover  420 , in which the cable loops around left semicircle  421  and folds back on itself. 
         [0046]      FIG. 25  shows the cable reel  400  and mobile conveyor  430  directly over the flipover  420 . The diverter  406  directs the cable  403  straight down toward flipover  420 . 
         [0047]      FIG. 26  shows the cable reel &amp; MOT on the right side of the filpover and moving away from the flipover in the direction of arrow A. As the MOT is traveling away from the filpover, the cable reel is rotating clockwise and spooling out the cable  403 . Diverter  406  diverts the cable  403  to the left in the direction of flipover  420 , in which the cable loops around right semicircle  423  and folds over as it begins to be laid out more or less straight. 
         [0048]      FIGS. 27 to 36  depict an alternate embodiment of this invention, in which two cable reels are utilized. In this embodiment the cables do not have to be folded back on themselves when laid out. 
         [0049]      FIG. 27  shows the initial position of cable reels  315  and  325 . Both reels are loaded with cable to their full capacity, which in this case is  400  m of cable, with reel  315  holding first section of cable  301  and reel  325  holding second section of cable  302 . Both reels are wired into a junction box (not shown) on the conveyor and each reel has a plug electrically connected to the junction box which is capable of easily being connected to and disconnecting a mating plug on the end of a power cable. As depicted, plug  301   a  of cable  301  is connected into reel  315 , and plug  301   b  is connected to electric house  314 . Thus cable  301  is powered up along with reel  315 , and therefore the conveyor—to which the reel is electrically connected—has power. Conversely, while plug  302   a  of cable  302  is connected into a plug in reel  315 , plug  302   b,  on the opposite end of cable  302 , remains unconnected. Therefore, reel  325  is not powered. Cables  303  and  304  (respectively the third and fourth section of cable) are laid out sequentially, although not all the cable has to be laid out in advance of the conveyor&#39;s operation, and one or more cables can be laid out while the conveyor is in operation. Cables  303  and  304  are laid out end to end and approximately parallel to the path to be taken by conveyor  308 . 
         [0050]    In  FIG. 28  conveyor  308  has moved approximately  400  m to the right in the direction of arrow 
         [0051]    A. Reel  315  has unspooled cable  301 . Alternatively, the relative positions of the cables and reels as shown in  FIG. 28  can be arrived at if reel  325  initially starts out empty, but in connected to cable  302 , with cable  302  being laid out in the same manner as cables  303 ,  304  and  305 . In such a case as the conveyor moved in the direction of Arrow A reel  325  would have spooled up cable  302  while reel  315  was unspooling and laying out cable  301  in the manner depicted in  FIGS. 27 and 28 . 
         [0052]    In  FIG. 29 : (a) plug  301   a  has been disconnected from reel  315  and is connected with the plug  302   b,  whose opposite member plug  302   a  is connected in reel  325 ; and (b) cable  303 &#39;s plug  303   a  is been connected with reel  315 . Reel  325  is now powdered up, while reel  315  is not. 
         [0053]      FIG. 30  depicts the conveyor having moved further to the right in the direction of Arrow A. Reel  325  has substantially unspooled cable  302 , and reel  315  has drawn up cable  303 . 
         [0054]    In  FIG. 31  plug  302   a  has been disconnected from reel  325 , which is empty, and plug  302   a  is now connected with plug  303   b.  As a result full reel  315 , in which plug  303   a  remains connected, is now powdered up by having a direct electrical connection with electric house  314 . Plug  304   a  is now connected with empty reel  325 , and reel  325  is not powered up. 
         [0055]    In  FIG. 32  the conveyor has moved further to the right. Reel  315  has unspooled cable  303  and reel  325  has drawn up cable  304 . 
         [0056]    In  FIG. 33 , plug  303   a  has been disconnected from reel  315  and connected with plug  304   b,  thus powering up full reel  325 . Empty reel  315  is no longer powered up. 
         [0057]    In  FIG. 34  the conveyor has again moved  400  m in the direction of arrow A. Reel  325  has unspooled cable  304 . Reel  315  remains empty. The conveyor  308  is now positioned to start on return leg in the direction of arrow B, with reel  325  remaining powered as it begins to take up cable. 
         [0058]    As shown, for the majority of the conveyor&#39;s run when one reel is spooling up cable the other reel is unspooling. During the run of the conveyor in the direction of arrow A, the reel unspooling the cable is live in that it maintains a direct connection with the electric house, while the reel spooling up cable is not powered up. In the return run in the direction of arrow B, the opposite is the case, in that the reel spooling up the cable is “live”, while the reel unspooling cable is not powered up. 
         [0059]      FIG. 35  is a plan view of the two reel embodiment of the present invention. Preferably, there is a small horizontal offset →X→ between the two cable reels  315  and  325 . This offset is to avoid interference between the cables and as they are picked up and laid down by the reels, and make it easier to swap cable ends at the transition points. 
         [0060]      FIG. 36  is an elevation view of the two reel embodiment showing the reels  315  and  325 , diverters  320   a  and  320   b,  as mounted on the conveyor  308  framework. 
         [0061]    It is to be understood that the form of this invention as shown is merely a preferred embodiment. Various changes may be made in the function and arrangement of parts; equivalent means may be substituted for those illustrated and described; and certain features may be used independently from others without departing from the spirit and scope of the invention as defined in the following claims.