Abstract:
In one case, an erosion control blanket is rolled into a configuration in which an end of the erosion control blanket is folded onto the erosion control blanket. This configuration can improve the unrolling the rolled erosion control blanket. Methods and apparatus for configuring erosion control blankets and configured erosion control blankets are provided.

Description:
[0001]    This application claims priority to U.S. Provisional Patent Application No. 60/950,537, filed Jul. 18, 2007, which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Soil erosion is a process by which wind and water carry away topsoil. Soil erosion is especially problematic where there is poor soil coherence and where the ground is sloped, such as in new slope embankments and channels, which may be created, for example, during construction of buildings and drainage systems. The loose soil can be carried away by water or wind and seeds of plants that might otherwise germinate to provide a root system to hold the soil in place are disturbed. Therefore, loose soil, embankments, and channel surfaces often require reinforcement, particularly during the pre-vegetated stage and early stages of plant growth, to prevent loss of soil, seeds, and seedlings until a mature root system develops to inhibit soil loss. 
         [0003]    One method of preventing soil erosion is to lay down an erosion control blanket over an area of soil that is to be protected. An erosion control blanket is a blanket made of fibrous material that may be placed over an area of soil to protect the soil from the effects of wind and water erosion. Erosion control blankets can be made, for example, of natural fibers, such as wheat straw, coconut fiber, and jute, or synthetic fibers, such as chopped or crimped polypropylene, or a blend of natural and/or synthetic fibers. The fibers can be compressed into a blanket or may be sewn to a net or held between two or more nets to form a blanket. 
         [0004]    After the erosion control blanket is manufactured, it can be formed into a roll using a roll up unit located at the end of the manufacturing process. The rolled erosion control blanket is also known as a rolled erosion control product (RECP). An erosion control blanket is generally between 4 feet and 16 feet wide and between 50 feet to 500 feet in total rolled out length. Of course, other widths and lengths are possible as required for a particular application. 
         [0005]    The finished rolled erosion control blankets can be packaged up into a bundle for shipping, for example, 16 rolls per bundle. The number of rolls per bundle can vary according to the type of rolled erosion control blanket produced. The bundle package is generally designed so that it fits into a normal 53 foot long trailer to transport the maximum amount of product in each trailer, and thus minimize transportation costs. 
         [0006]    To further reduce transportation costs, erosion control blankets can be rolled tighter and tighter to reduce the diameter of each roll and allow more rolls to be loaded into a trailer. For example, an 8 foot wide by 112.5 foot long (100 square yards) erosion control blanket may be rolled to 12 inches in diameter to fit 416 rolls into a trailer or may even be rolled to 10 inches in diameter to fit 500 rolls onto a trailer. 
         [0007]    When the rolled erosion control blanket is ready for use, it can be placed on the ground and unrolled by a user, generally by kicking the roll along the ground. However, one problem with rolling the erosion control blankets more tightly is that the end of the rolled erosion control blanket (i.e., the core of the rolled erosion control blanket) becomes bunched up and does not unroll easily. The user must therefore either spend extra time to unroll the end of the rolled erosion control blanket by hand, leave it rolled up, or cut the end of the rolled erosion control blanket off with a knife. In either case, the extra steps waste time and money. Therefore, the requirement of winding tighter rolled erosion control blankets to reduce transportation costs creates a problem for a user when the user cannot easily unroll all of the rolled erosion control blanket. 
       SUMMARY 
       [0008]    In one example, an erosion control blanket may include a first end, a second end, and a folded portion including the first end folded onto the erosion control blanket to form a folded edge. The erosion control blanket is configured as a roll having the folded portion disposed at a core of the roll. This configuration allows for the erosion control blanket to be rolled tightly, while still being easy for a user to unroll right to the end. To unroll, a user can roll the roll configuration of the erosion control blanket along the ground and then unfold the folded core portion of the erosion control blanket to finish the unrolling process. 
         [0009]    In another example, a method of rolling the erosion control blanket is provided that includes folding a first end of the erosion control blanket onto the erosion control blanket to form a folded edge and rolling the erosion control blanket so that the folded edge forms a core of the rolled erosion control blanket. 
         [0010]    In another example, an apparatus for rolling an erosion control blanket is provided. The apparatus includes at least one roller for forming the blanket into a roll and a diversion unit for diverting a first end of the erosion control blanket away from the at least one roller such that a folded edge of the erosion control blanket is rolled by the at least one roller to form a core of the rolled erosion control blanket. 
         [0011]    Additional examples will be set forth in the description that follows and will be obvious from the description, or may be learned through the practice of the invention. The objects and advantages of the description herein will be attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a diagram of an erosion control blanket folded according to one example; 
           [0013]      FIG. 2  is a diagram of an erosion control blanket rolled according to an example; 
           [0014]      FIG. 3  is a diagram of an erosion control blanket folded according to another example; 
           [0015]      FIG. 4  is a diagram of an erosion control blanket rolled according to another example; 
           [0016]      FIG. 5  is a diagram of a roll up unit according to an example that may be used to produce a rolled erosion control blanket; 
           [0017]      FIG. 6  is a diagram of a roll up unit according to another example that may be used to produce a rolled erosion control blanket; and 
           [0018]      FIG. 7  is a diagram of a roll up unit according to yet another example that may be used to produce a rolled erosion control blanket. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]      FIG. 1  is a diagram of an erosion control blanket  10  folded according to an example prior to being rolled up. An end portion of the erosion control blanket  10  is folded back on itself, creating a folded portion  12  and an unfolded portion  14  of the erosion control blanket  10 . In one example, the folded portion  12  is between 3 to 20 feet long. In another example, the folded portion  12  is 10 feet long. The erosion control blanket  10  is then rolled up starting with the folded edge  16 , (i.e. the crease of the fold). As shown in  FIG. 1 , the folded portion  12  may be folded back on top of the erosion control blanket  10 . Alternatively, the folded portion  12 , may be folded underneath the erosion control blanket  10 , as shown in  FIG. 3 . 
         [0020]      FIG. 2  shows a diagram of the erosion control blanket  10  of  FIG. 1  after it has been rolled up in accordance with an example. Similarly,  FIG. 4  shows a diagram of the erosion control blanket  10  of  FIG. 3  after it has been rolled up in accordance with another embodiment of the invention. As shown in  FIGS. 2 and 4 , the folded portion  12  of the erosion control blanket  10  is rolled first to form the core of the rolled erosion control blanket  10 . The unfolded portion  14  of the erosion control blanket  10  is then rolled around the folded portion  12  of the erosion control blanket  10 . For purposes of illustrations,  FIGS. 2 and 4  show a space  18  between the rolled layers of the rolled erosion control blanket  10 . In another example, the layers of the rolled erosion control blanket  10  can be rolled such that they are compressed together without a space  18  between them. 
         [0021]    After the erosion control blanket  10  is unrolled by a user, as shown in  FIGS. 1 and 3 , the folded portion  12  of the erosion control blanket  10  can be opened by grabbing the edge of the erosion control blanket  20  and unfolding the folded portion  12 . Unfolding the folded portion  12  of the erosion control blanket  10  removes the need to painstakingly unroll the end portion by hand, or cut it off with a knife. In this embodiment, tighter rolls can be formed while eliminating the extra time needed to unroll or cut off an end portion of the end of the erosion control blanket  10 . In one example, up to about 9% of the erosion control blanket  10  can be saved by unrolling, as opposed to cutting off the end of the erosion control blanket  10 . 
         [0022]      FIG. 5  is a diagram of a roll up unit  300  that can be used to roll an erosion control blanket  10  in accordance with an example. The roll up unit  300  can be located at the end of an erosion control blanket manufacturing process to roll up the erosion control blanket  10  as the erosion control blanket  10  is produced. The roll up unit  300  includes a blanket slide  310 , a series of hooks  312 , a driven top roller  314 , a driven first bottom roller  316 , and a driven second bottom roller  318 . 
         [0023]    An exemplary method of operating the roll up unit  300  is described below. The erosion control blanket  10  exits the manufacturing process (not shown) and enters the roll up unit  300  in the direction of arrow A along the blanket slide  310 . Under the power of gravity and the force from the manufacturing process, the blanket slide  310  guides the erosion control blanket  10  down a slope and then onto the hooks  312 , which are located at a first position  312   a . The hooks  312  include a number of hooks attached to a frame (not shown), for example, by welding. The hooks  312  are arranged along the width of the erosion control blanket  10 . The hooks  312  at the first position  312   a  catch or snag the erosion control blanket  10  as it falls off the end of the blanket slide  310 . 
         [0024]    The hooks  312  and frame are connected to actuators (not shown), which are capable of moving the hooks  312  and the end of the control blanket  10  from the first position  312   a  to a second position  312   b  along the direction of arrow B. The actuators and rollers  314 ,  316 ,  318  are programmably logic controlled (PLC) so that they may be moved in a preprogrammed sequence and at preprogrammed speeds. The PLC controls the sequence and timing of events to ensure acceptable product and a reliable process. After the hooks  312  have snagged or caught the erosion control blanket  10 , the actuators raise the end  20  of the erosion control blanket  10  to the second position  312   b  as instructed by the PLC program. Alternatively, the hooks  312  may be raised by hand. The second position  312   b  of the hooks  312  can control the length of the folded portion  12  (shown by arrow  320 ). In one example, the second position  312   b  is located at a distance from the first position  312  such that the length of the folded portion  12  is approximately 10 feet. 
         [0025]    While the actuators lift the end  20  of the erosion control blanket  10 , the manufacturing process continues to make and feed the erosion control blanket  10  down the blanket slide  310 , causing the folded edge  16  of the erosion control blanket  10  to descend down into the rollers  314 ,  316 ,  318 . The folded edge  16  is then pinched between the three rollers  314 ,  316 ,  318  which start rolling the erosion control blanket  10  into a roll. The driven top roller  314  can be weighted and may have rubber material on its surface to prevent slipping. The driven top roller  314  is on the top of the rolled erosion control blanket  10  as it is being rolled up and is designed to move up with the rolled erosion control blanket  10  as the roll diameter gets larger. 
         [0026]    After the erosion control blanket  10  begins to be rolled up, the PLC causes the actuators to allow the hooks  312  to be pulled down from the second position  312   b  to the first position  312   a . This allows the folded portion  12  to be rolled into the core of the rolled erosion control blanket  10 . The speed of the rollers  314 ,  316 ,  318  may be adjusted to control how tightly the erosion control blanket  10  is wound. 
         [0027]    Once the folded portion  12  is rolled up and the hooks  312  have descended back to the first position  312   a , the rollers  314 ,  316 ,  318  will continue to roll up the erosion control blanket  10  and will pull, or rip, the snagged end  20  off of the hooks  312  and into the erosion control blanket  10 . At this point the fold has been achieved and the rollers  314 ,  316 ,  318  continue to roll up the rest of the erosion control blanket  10  until the desired final length is achieved. In one embodiment, the final length may be about 112.5 feet. Once the roll is proper size, the PLC instructs the manufacturing process to cut off the end of erosion control blanket  10 . The rolled erosion control blanket  10  is thus completed. The top driven roller  314  is raised and the finished rolled erosion control blanket  10  is removed from the bottom two rollers  316 ,  318 . The roll up unit is now ready to being the process over to form the next rolled erosion control blanket  10 . 
         [0028]    The fold back capability of the roll up unit  300  may be designed so that it may be turned on or off by a user selectable on/off type feature, such as a switch, so that the roll up unit  300  may produce a rolled erosion control blanket  10  without a folded portion  12  at the core. 
         [0029]      FIG. 6  is a diagram of a roll up unit  400  that may be used to roll an erosion control blanket  10  in accordance with another embodiment of the invention. As with roll up unit  300 , roll up unit  400  may be located at the end of an erosion control blanket manufacturing process. The roll up unit  400  includes a primary blanket slide  410 , a secondary blanket slide  412 , a driven top roller  414 , a driven first bottom roller  416  and a driven second bottom roller  418 . 
         [0030]    An exemplary method of operating the roll up unit  400  is described below. The erosion control blanket  10  exits the manufacturing process (not shown) and enters the roll up unit  400  in the direction of arrow A along the primary blanket slide  410 . Under the power of gravity and the force from the manufacturing process, the blanket slide  410  guides the erosion control blanket  10  down a slope and then straight down onto the secondary blanket slide  412 , which is located at a first position  412   a . The secondary blanket slide  412  at the first position  412   a  catches the erosion control blanket  10  as it falls off the end of the primary blanket slide  410 . The secondary blanket slide  412  is connected to actuators (not shown), which are capable of moving the secondary blanket slide  412  from a first position  412   a  to a second position  412   b  along the direction of arrow C. Similarly, to roll up unit  300 , the actuators and rollers  414 ,  416 ,  418  are programmably logic controlled (PLC) so that they may be moved in a preprogrammed sequence and a preprogrammed speeds. 
         [0031]    The secondary blanket slide  412  includes a driven roller/conveyer (not shown), which moves the end  20  of the erosion control blanket  10  along the surface of the secondary blanket slide  412  in the direction shown by arrow D. The portion of the erosion control blanket  10  collected on the secondary blanket slide  412  will become the folded portion  12 . Once a desired length of the folded portion  12  of the erosion control blanket  10  is collected on the secondary blanket slide  412 , the driven roller/conveyer is turned off and the actuators move the secondary blanket slide  412  with the folded portion  12  of the erosion control blanket  10  to the second position  412   b . In one embodiment, the length of the folded portion  12  collected on the secondary blanket slide  412  is from about 3 to 20 feet in length, preferably about 10 feet in length. In another embodiment, the distance from the first position  412   a  to the second position  412   b  is about 6 inches. At this point, the front edge of secondary blanket slide  412  is located behind the end of the primary blanket slide  410 . The manufacturing process continues to feed the erosion control blanket  10  down the primary blanket slide and so the edge of the fold  16  descends down into the rollers  414 ,  416 ,  418 . 
         [0032]    In this case, the edge of the fold  16  of the erosion control blanket  10  is pinched between the rollers  414 ,  416 ,  418 , which start rolling the erosion control blanket  10  into a roll. This begins to pull the folded portion  12  of the erosion control blanket  10  off of the secondary blanket slide  412  and continues until all of the folded portion is pulled into the rollers  414 ,  416 ,  418 . 
         [0033]    After the folded portion  12  is rolled up, the rollers  314 ,  316 ,  318  will continue to roll up the erosion control blanket  10  until the desired final length is achieved. In one embodiment, the final length may be about 112.5 feet. Once the roll is proper size, the PLC instructs the manufacturing process to cut off the end of erosion control blanket  10 . The rolled erosion control blanket  10  is thus completed and the finished rolled erosion control blanket  10  is removed from the roll up unit  400 . The PLC then resets the roll up unit  400  by causing the actuators to move the secondary blanket slide  412  forward to the first position  412   a . The roll up unit  400  is then ready to being the process over to form the next rolled erosion control blanket  10 . 
         [0034]      FIG. 7  is a diagram of a roll up unit  500  that can be used to roll a erosion control blanket  10  in accordance with another example. Similarly to roll up units  300  and  400 , roll up unit  500  may be located at the end of an erosion control blanket manufacturing process. The roll up unit  500  includes a blanket slide  510 , a driven top roller  514 , a driven first bottom roller  516  and a driven second bottom roller  518 . 
         [0035]    An exemplary method of operating the roll up unit  500  is described below. The erosion control blanket  10  exits the manufacturing process (not shown) and enters the roll up unit  500  in the direction of arrow A along the blanket slide  510 . Under the power of gravity and the force from the manufacturing process, the blanket slide  510  guides the erosion control blanket  10  down a slope. The front edge  20  of the erosion control blanket  10  is grabbed by an operator  512  and is pulled back to a pre-determined position in front of the roll up unit  500 , while the manufacturing process continues to feed the erosion control blanket  10  to the roll up unit  500 . In one embodiment, the front edge  20  may be pulled to a distance of 10 feet from the roll up unit  500 . 
         [0036]    Once the front edge  20  of the erosion control blanket  10  has been pulled to a predetermined position in front of the roll up unit  500 , the operator  512  allows the folded edge  16  of the erosion control blanket  10  to feed into the rollers  514 ,  516 ,  518 . The folded edge  16  is pinched between the rollers  514 ,  516 ,  518 , which start rolling the erosion control blanket  10  into a rolled erosion control blanket  10 . This begins to pull the folded portion  12  of the erosion control blanket  10  into the rollers and winds it up as the core. The operators  512  moves towards the roll up unit  500  the front edge  20  to allow all of the folded portion  12  to be pulled into the rollers  514 ,  516 ,  518  and rolled up. 
         [0037]    After the folded portion  12  is rolled up, the rollers  514 ,  516 ,  518  will continue to roll up the erosion control blanket  10  until the desired final length is achieved. In one embodiment, the final length can be about 112.5 feet. Once the roll is the proper size, the PLC instructs the manufacturing process to cut off the end of the erosion control blanket  10 . The rolled erosion control blanket  10  is thus completed and the finished rolled erosion control blanket  10  is removed from the roll up unit  500 . The operator  512  then grabs the end of the next erosion control blanket  10  to begin the process over to form the next rolled erosion control blanket  10 . 
         [0038]    It is to be understood that application of the teachings of the present invention to a specific problem or environment will be within the capability of one having ordinary skill in the art in light of the teachings contained herein. Furthermore, although certain advantages have been described above, those skilled in the art will recognize that there may be many others. For example, the steps in the methods described herein may be performed in different orders, or may include some variations, such as alternative materials having similar functions. Accordingly, the claimed invention is not limited by the embodiments described herein but is only limited by the scope of the appended claims.