Patent Abstract:
A method for packaging conventional silt fencing and a product produced by the method Silt fabric is attached to a number of evenly spaced stakes. The stakes are then bunched together so that the silt fabric hangs between the stakes in descending loops. The bunching is continued until all the stakes lie close together in one plane. The loops of silt fabric are then wrapped tightly around the stakes. Securing bands are then placed around the assembly to create a flat pack.

Full Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
         [0001]    Not Applicable  
         STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0002]    Not Applicable  
         MICROFICHE APPENDIX  
         [0003]    Not Applicable  
         BACKGROUND OF THE INVENTION  
         [0004]    1. Field of the Invention  
           [0005]    This invention relates to the field of soil erosion control. More specifically, the invention comprises a new method of manufacturing and packing sections of silt fence.  
           [0006]    2. Description of the Related Art  
           [0007]    Soil erosion is a constant problem in construction work, where the bare soil must often be left exposed to rain for considerable periods. Traditionally, hay bails were staked to the ground in order to slow water run-off down bare slopes. While effective, this technique was labor intensive and had inherent shipping and storage problems—owing to the weight of the bales. The more modem approach is to use silt fencing.  
           [0008]    A silt fence is a porous barrier fabric which is attached to and stretched between a number of stakes. The stakes are driven into the ground in positions needed to stretch the fabric across the anticipated direction of water flow. The fabric is designed to allow the passage of water, but to encourage the deposition of any sediment being carried in the water. The result is that sediment builds up on the upstream side of the fabric, with the silt fence ultimately tending to bury itself.  
           [0009]    Numerous prior art patents pertain to silt fences and methods of producing and installing them. These prior art patent include U.S. Pat. Nos. 6,158,923, 6,053,665, 5,944,114, 5,921,709, 5,915,878, 5,622,448, 5,345,741, and 4,756,511.  
           [0010]    [0010]FIG. 1 illustrates a typical prior art silt fence. A plurality of evenly spaced stakes  12  are provided. Silt fabric  10  is placed over stakes  12 , then affixed to stakes  12  by staples or other fastening means. The user places the fence in position by driving points  16  of stakes  12  into the ground, with the lower portion of silt fabric  10  being buried in a shallow trench.  
           [0011]    While FIG. 1 illustrates the components of a silt fence, it does not accurately reflect how such fences are typically manufactured. FIG. 2 shows roll  28 , which is formed by a plurality of stakes  12  attached to silt fabric  10 . A silt fence is typically made by chucking center stake  36  in a rotating carriage, then attaching the starting end of silt fabric  10  to it. Center stake  36  is then rotated to wind silt fabric  10  around itself. At fixed intervals, another stake  12  is brought in and stapled to silt fabric  10 . The winding continues until a complete roll  28  is formed. It is then taped, tied, or banded to lock it in position for transportation and storage.  
           [0012]    [0012]FIG. 2 illustrates roll  28  having eight stakes  12 . Roll  28  can be made larger or smaller. Those skilled in the art will realize that the prior art manufacturing process described is an intermittent one; i.e., once a roll is formed, the process is stopped to remove that roll and start forming a new one. This represents a disadvantage, in that it limits the speed of production. It also causes problems with any printing performed on silt fabric  10 . Many purchasers want to have their names and logos printed on the silt fabric itself The best printing methods for this purpose are those using a wet printing plate. The printing dyes employed are dissolved in a liquid carrier, which must be quite volatile (in order for the printing to dry rapidly). Thus, the wet printing process is very sensitive to any pauses in the production. If the feed of silt fabric  10  is halted for significant periods, the dye solutions will dry on the printing plate and the print quality will deteriorate. The prior art intermittent production process therefore compromises printing quality on silt fabric  10 .  
           [0013]    The roll method has two additional drawbacks. First, rolls  28  do not stack efficiently, since their circular cross section inherently produces wasted space. Second, roll  28  is cumbersome to install. Those skilled in the art will realize that roll  28 —as illustrated in FIG. 2—is modestly sized. Often these rolls will be 100 feet long. A typical installation would be in the range of 100 feet to 10,000 feet long. It is very cumbersome to unroll many hundreds of feet of silt fencing packaged in the roll form.  
           [0014]    It is also fairly common to need a length which is less than the entire roll. In such a case, the user must lift roll  28  by its ends and unroll the needed amount. The user then cuts the needed amount free from the rest of the roll. As roll  28  can be heavy, this approach often means that two people are needed.  
           [0015]    Alternatively, the user can unroll roll  28  by rolling it along the ground until the needed amount is laid flat. The user then removes the needed amount and re-rolls roll  28 . This approach requires the user to lift a heavy object (roll  28 ) off the back of a truck, perform the operation, and then lift it back on to the truck.  
           [0016]    Accordingly, the prior art methods of packing silt fencing are limited in that they:  
           [0017]    1. Typically require an intermittent manufacturing process, thereby limiting production speed and compromising print quality;  
           [0018]    2. Do not lend themselves to efficient packing; and  
           [0019]    3. Render the silt fence cumbersome to deploy.  
         BRIEF SUMMARY OF THE INVENTION  
         [0020]    The present invention eliminates the disadvantages inherent in the prior art by placing the silt fence in a flat-pack configuration. With reference to FIG. 4, stakes  12  are evenly spaced and silt fabric  10  is evenly draped over them by any suitable means to form a series of loops  14 . Silt fabric  10  is then attached to each stake  12  at the point where it drapes over each stake  12 .  
           [0021]    Stakes  12  are then moved closer to each other as shown in FIG. 6, with the result that loops  14  grow longer and more narrow. FIG. 7 shows stakes  12  bunched tightly together, with the result that loops  14  are now very long and very narrow. As stakes  12  are held in position, loops  14  are then wrapped around stakes  12  as indicated by the arrow.  
           [0022]    [0022]FIG. 8 shows stakes  12 —still being held in position—with loops  14  wrapped around them. In FIG. 9, securing straps  24  have been placed around the assembly to create flat pack  26 . This entire process can be carried out on a linear assembly line without intermittently stopping the motion.  
           [0023]    The objects and advantages of the present invention are:  
           [0024]    1. To provide an improved method of packing and storing silt fence which can be carried out on a linear assembly line without intermittently stopping the linear motion;  
           [0025]    2. To provide an improved method of packing and storing silt fence which does not waste storage space; and  
           [0026]    3. To provide an improved method of packing and storing silt fence which enables the user to easily pull off a short section of silt fence without having to lift the entire pack. 
       
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0027]    [0027]FIG. 1 is an isometric view, showing a completed silt fence.  
         [0028]    [0028]FIG. 2 is an isometric view, showing the prior art method.  
         [0029]    [0029]FIG. 3 is an isometric view, showing the manufacture of the present invention.  
         [0030]    [0030]FIG. 4 is an isometric view, showing the manufacture of the present invention.  
         [0031]    [0031]FIG. 5 is an isometric view, showing the addition of staples.  
         [0032]    [0032]FIG. 6 is an isometric view, showing the bunching of the loops.  
         [0033]    [0033]FIG. 7 is an isometric view, showing the completion of the bunching of the loops.  
         [0034]    [0034]FIG. 8 is an isometric view, showing the wrapping of the loops around the stakes.  
         [0035]    [0035]FIG. 9 is an isometric view, showing the strapping of the flat pack. 
     
    
     REFERENCE NUMERALS IN THE DRAWINGS  
       [0036]    [0036] 10  silt fabric  
         [0037]    [0037] 12  stake  
         [0038]    [0038] 14  loop  
         [0039]    [0039] 16  staple  
         [0040]    [0040] 18  stake top  
         [0041]    [0041] 20  starting color patch  
         [0042]    [0042] 22  ending color patch  
         [0043]    [0043] 24  securing strap  
         [0044]    [0044] 26  flat pack  
         [0045]    [0045] 28  roll  
         [0046]    [0046] 30  point  
         [0047]    [0047] 32  first stake  
         [0048]    [0048] 34  last stake  
         [0049]    [0049] 36  center stake  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0050]    [0050]FIG. 3 illustrates the major components involved in the process. A plurality of stakes  12  are evenly spaced along a production line by any conventional means. A strip of silt fabric  10  is then fed to the top of the plurality of stakes  12 . The illustration simply shows a long ribbon of silt fabric  10  being draped over stakes  12 . This can also be accomplished by a linear feed of silt fabric  10  (such as off a large master roll) descending down over a line of moving stakes  12 . In the example shown in FIG. 3, an assembly line could move stakes  12  from right to left in the view, as the ribbon of silt fabric  10  is deposited over their tops.  
         [0051]    [0051]FIG. 4 shows silt fabric  10  laid evenly over stakes  12 . However this operation is carried out, significant result is that silt fabric  10  must be placed so as to create a plurality of even loops  14  between stakes  12 . The loops need not be exactly alike, but it is important to have them approximately equal in length.  
         [0052]    While stakes  12  and silt fabric  10  are in the relationship shown in FIG. 4, silt fabric  10  must be attached to stakes  12 . FIG. 5—a detail view—shows the addition of stapes  16 . Two or more staples  16  are driven through each portion of silt fabric  10  that lies on top of a stake  12 . Once staples  16  are in place, the length of each loop  14  is fixed.  
         [0053]    The reader should appreciate that while staples are particularly effective from a strength and cost standpoint, many other types of fasteners could be used. These would include nails, screws, adhesives, stitching, slats, tie cords, and the like.  
         [0054]    The next step in the manufacturing process is shown in FIG. 6. After staples  16  are in place, stakes  12  are pushed closer together—as shown by the arrow. The result is that loops  14  begin to lengthen and become more narrow. This process continues until stakes  12  are bunched closely together in a single plane, as shown in FIG. 7. The reader will note that loops  14  are by this point long and narrow. It is advantageous to use gravity to orient loops  14  by allowing them to descend below the production line during this process. However, the use of gravity is not the only way to accomplish this. A set of guiding rods placed through each loop  14  could be used to pull them in any direction desired. Many other conventional mechanisms could be employed.  
         [0055]    Once the bunching of stakes  12  is complete, the plurality of loops  14  is wrapped around stakes  12  in the direction indicated by the arrow. Stakes  12  are held in position as loops  14  are wrapped snugly around them. This wrapping process serves to pull stakes  12  even closer together.  
         [0056]    [0056]FIG. 8 shows stakes  12  with the plurality of loops  14  wrapped tightly around them. The reader will observe that each loop  14  has been pressed flat. As silt fabric  10  is thin and highly flexible, this operation does not place undue stress on the fabric.  
         [0057]    The assembly shown in FIG. 8 will not remain in its compact state without an additional step. FIG. 9 shows the addition of two securing straps  24 . These can be metal bands, plastic bands, tape, or the like. Their function is to tightly bind the components together. Once bound, the result is a unitary structure referred to as flat pack  26 . Flat pack  26  can be handled as a unit. Many flat packs  26  can be vertically stacked with very little waste of space. Flat packs  26  can also be placed on their narrow edges and stored in that fashion with very little waste of space.  
         [0058]    The reader should appreciate that although stakes  12  have been illustrated as square, the method can be employed for stakes having many different cross-sections and characteristics.  
         [0059]    When a user wants to pull the silt fence out of flat pack  26 , it is important to know which end to start from. The user first removes securing straps  24 . The user then pulls the portions of loops  14  resting over the top of flat pack  26  off to the left in FIG. 9. The user then pulls first stake  32  off to the left. The user then continues moving first stake  32  to the left. This action results in each successive loop  14  being unfurled out into a tight sheet and pulling the next stake  12  out of flatpack  26 .  
         [0060]    Those skilled in the art will realize that flat pack  26  can be made with many more stakes  12  than are shown in FIG. 9. In such a case, the user may not wish to use all of the flat pack. If so, the user simply stops pulling at the desired point and makes a transverse cut across silt fabric  10 . He or she is able to pull off any desired amount without having to lift or move flat pack  26 .  
         [0061]    So long as the user starts with first stake  32 , the unpacking operation will be smooth. Those skilled in the art will realize, however, that if the user starts pulling with last stake  34  (pulling it to the right as shown in FIG. 9), the operation will not be smooth. If the user begins pulling with last stake  34 , he will have to pull the loops under flat pack  26  in order to start pulling last stake  34  free. This is difficult without moving the whole flat pack  26 . The goal is to have flat pack  26  remain stationary while the user pulls off the desired length of silt fencing. Thus, it is important to be sure the user starts pulling on the correct end.  
         [0062]    It is also important to ensure that flat pack is oriented as shown in FIG. 9; i.e., with the ends of loops  14  on its upper surface. If it is inverted, then the user will have difficulty pulling loops  14  out from beneath flat pack  26 .  
         [0063]    To ensure these goals, a color designation system is employed. First stake  32  has starting color patch  20  on its upper surface at its upper end (nearest the viewer in FIG. 9). Likewise, last stake  34  has ending color patch on its upper surface at its upper end. The colors employed should be easily distinguished—such as blue and yellow. These color cues will assist persons stacking flat packs  26 . As an example, when placed on a truck, flat packs  26  should be placed with the color patches facing upward, and with first stake  32  toward the rear of the truck (or toward whichever side the silt fencing will be unloaded from).  
         [0064]    The manufacturing operations described in FIGS. 3 through 9 could be carried out using a variety of mechanisms. The actual mechanisms employed are not significant to the present invention. However, it is important for the reader to understand that all of these operations can be carried out while stakes  12  are moving down a linear assembly line. In FIGS. 3 and 4, silt fabric  10  can be properly fed onto the plurality of stakes  12  as stakes  12  move transversely down an assembly line (with the stakes moving from right to left as shown in FIG. 4). Staples  16  can also be added while the line continues to move.  
         [0065]    The bunching operations described in FIGS. 6 and 7 can be accomplished by transferring stakes  12  onto a decelerating conveyor. A desired length of silt fencing is then cut free and the wrapping of loops  14  (FIGS. 7 and 8) can be performed. There is no need to stop and start the moving assembly line, as in the prior art rolling approach.  
         [0066]    Accordingly, the reader will appreciate that the proposed invention can readily create a silt fence stored in a convenient flat pack. The invention has further advantages in that it:  
         [0067]    1. Can be carried out on a linear assembly line without intermittently stopping the linear motion;  
         [0068]    2. Provides an improved method of packing and storing silt fence which does not waste storage space;  
         [0069]    3. Enables the user to easily pull off a short section of silt fence without having to lift the entire pack; and  
         [0070]    4. Enables the user to easily inventory a stack of silt fencing since the flat pack has little wasted space.  
         [0071]    Although the preceding description contains significant detail, it should not be construed as limiting the scope of the invention but rather as providing illustrations of the preferred embodiment of the invention. As an example, many different methods could be employed to attach silt fabric  10  to stakes  12 . As another example, mechanisms could be employed to align loops  14  in a single orientation, rather than using gravity to align them by suspending them below stakes  12 . Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given.

Technology Classification (CPC): 4