Abstract:
A method of recompressing bales of fibrous material which uses longer bales and a lesser pressure force at the plunger head to achieve higher quality recompressed bales having nearly the same density of those made through the standard process.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Technical Field.  
           [0002]    This invention relates to the recompression of large bales of fibrous material, and more particularly to an improved method of recompressing said bales.  
           [0003]    2. Background.  
           [0004]    Hay and other forages for feeding and bedding animals must often be transported over great distances from the place of production to the location of the animals. It is not uncommon to ship large quantities of hay and straw to dairies, feed lots, or race tracks located near or in metropolitan areas, and to other locations to where hay, grass and straw cannot be grown, or where there is limited availability of land on which to grow hay, grass and straw.  
           [0005]    For purposes of this disclosure, the term “hay” will be used in a generic sense to describe cut foliage, particularly normal hay, such as that made from alfalfa, grasses used as feed, and straw. Also, while this invention is ideally used to recompress bales of “hay,” said generic term is intended to include any material that may be recompressed using the invented method, including, but not limited to cotton, cardboard, etc.  
           [0006]    Hay is typically harvested in the United States by use of hay balers, either of the type that produce square bales or, round bales. The use of square bales is by and far the most common method of harvesting hay. These bales are constructed of predetermined densities by the bale machines within a certain normal range of densities. In determining the density of the hay in the standard field bale, consideration is given to optimizing storage life, optimizing food value of the product, minimizing damage through high or low moisture contents and the actual weight of the bale that has to be handled by the farmer or stockman.  
           [0007]    However, it is uneconomical and impractical to ship these same standard field bales overseas. The freight costs because of the low density and high volumes is often prohibitive. Therefore, a number of methods have been developed to increase the density of the hay bales so as to minimize freight costs. One of these methods involves taking a field bale, or portion thereof, and recompressing it (typically after cutting the field bale into smaller portions) to approximately half its original volume. Then, these recompressed bales can be stacked into standard dry cargo freight containers which can then be transported to a seaport and loaded aboard a containerized cargo ship for shipment overseas.  
           [0008]    Through such a process, a field bale of alfalfa or grass hay with approximate dimensions of 32″×35″×96″ (32″×48″×96″) bales are also common) and a density of 12-14 pounds per cubic foot is cut and recompressed into 12″×16″×22″ (or 16″×18″×22″) bales which have a density of ˜28 pounds per cubic foot. U.S. Pat. No. 5,893,309 (Ast) protects this process. This 22″ length is the industry standard export bale length. These 12″×16″×22″ bales weigh on average 65 pounds, and the 16″×18″×22″ bales weigh on average 100 pounds.  
           [0009]    There are two drawbacks with this process. The first drawback revolves around the amount of pressure required to recompress the bale. As with any typical bale of fibrous material, the bale is held together through use of a plurality of ties or straps. These straps/ties are typically baling straps, twine or wire.  
           [0010]    In order to strap/tie the recompressed bale, the bale must be overcompressed six to ten inches to allow for proper operation of the strapping/tying apparatus. With regard to a 22″ bale, the resulting overcompression is 6 to 10 inches (anywhere from 27% to 46% of the length of the bale). Thus, the prior art press actually overcompresses the bale down to roughly 13 inches long, ties the strapping, and then releases the compression, thereby allowing the bale to expand back to the desired 22 inch length. This degree of overcompression requires high pressure on the face of the hydraulic plunger, often ranging from 800 to 1300 pounds per square inch.  
           [0011]    Using high pressure to recompress the bale has two undesired side effects. The first is that if the fibrous material has a percentage of moisture which is more than 1-2% above ideal, the hay will tend to mat into essentially a 22″ long hay pellet or brick. Obviously, buyers are not pleased when they cut the strings on a hay bale and find a matted bale which does not flake apart into easy to handle and easy to eat portions.  
           [0012]    The second side effect is if the hay is a little dry and fine stemmed, the high force will disintegrate the stem, thereby turning the hay into powder. Obviously, buyers are not pleased when they cut the strings on a hay bale and a portion of the bale disintegrates into dust.  
           [0013]    The second “drawback” with the 22-inch bale process is in stacking them inside a standard cargo container. A standard cargo container is 92 inches wide, and thus four 22-inch bales can fit lengthwise across a container, with 4 inches of wasted space (air).  
           [0014]    What is needed is a method of recompressing bales of fibrous material which does so using low pressure, thereby reducing matting and dusting, using less power, needing less iron/steel framework to contain the lowered pressure needed, and causing less wear and tear on the compression equipment. What is also needed is a method of recompressing bales of fibrous material which eliminates wasted space in cargo containers when said bales are stacked therein. The present invention solves these needs.  
         SUMMARY OF THE INVENTION  
         [0015]    The present invention is a method of producing recompressed bales of fibrous material from previously compressed fibrous material. One embodiment of this method comprises the steps of first selecting a quantity of previously compressed fibrous material from 55 to 65 inches long. Then, this material is introduced into a recompression chamber and is recompressed down to 18 to 22 inches long. This recompressed material is tied at 18 to 22 inches long. This recompressed material is transferred, under compression, to a decompression chamber where the material is held for a sufficient period of time for trapped air to escape from the recompressed material and for the material to lose resiliency. This recompressed material is then ejected from the decompression chamber, whereupon the material expands out to a bale of approximately 28 inches in length.  
           [0016]    Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description wherein I have shown and described only the preferred embodiment of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiment are to be regarded as illustrative in nature, and not as restrictive. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    [0017]FIG. 1 is a schematic representation of the side view of the recompressing apparatus embodying the principles of the invention.  
         [0018]    [0018]FIG. 2 is a schematic representation of the side view of the recompressing apparatus of FIG. 1 showing a step following the view of FIG. 1.  
         [0019]    [0019]FIG. 3 is a schematic representation of the side view of the recompressing apparatus of FIG. 1 showing a step following the view of FIG. 2.  
         [0020]    [0020]FIG. 4 is a schematic representation of the side view of the recompressing apparatus of FIG. 1 showing a step following the view of FIG. 3.  
         [0021]    [0021]FIG. 5 is a schematic representation of the side view of the recompressing apparatus of FIG. 1 showing a step following the view of FIG. 4.  
         [0022]    [0022]FIG. 6 is a schematic representation of the side view of the recompressing apparatus of FIG. 1 showing a step following the view of FIG. 5.  
         [0023]    [0023]FIG. 7 is a perspective view of a needle and knotter assembly. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]    First referring to FIGS. 1 and 2 the fibrous material bale recompressor  10  is shown to advantage. The bale recompression chamber  13  is defined by end plate  34 , top plate  36  and side plates (not shown). In the preferred embodiment the recompression chamber  13  unenclosed and is open at the bottom to decompression chamber  14  which is defined by end plate  34 , side plates (not shown) and decompression front plate  35 .  
         [0025]    It is common with fibrous material bale recompression to create a continual column of hay formed by aligning a plurality of bales, or portions of bales end to end. A length of material or “charge” from this continual column of hay is selected and recompressed. A charge is typically longer than a standard field bale, however the term “charge” as used herein is also intended to include appropriately lengthed field bales. It is preferred for this invention that an uncompressed charge  37  of fibrous material be 55 to 65 inches long, depending on the weight and density of the continual column of hay.  
         [0026]    Referring to FIG. 1, a charge  37  is placed onto the bottom slide plate  26  in a position where the charge  37  is correctly positioned for insertion into the recompression chamber  13 . FIG. 1 shows a side plate entrance for the charge, however other entrances, such as a bottom entrance, are also envisioned and would work as well.  
         [0027]    Once the charge  37  has been properly positioned on bottom slide plate  26 , in position to be recompacted, a recompression plate(s)  15 , attached to a recompression ram  16 , pushes the charge  37  into the recompression chamber  13 , as shown in FIG. 2.  
         [0028]    In one embodiment, in the process of being pushed into recompression chamber  13 , charge  37  preferably intercepts a wrapping means comprising four or more strings of bale twine  32 , which originates from four or more twine spools  33 , said twine  32  being threaded through needles  20  and attached to knotter  19 . Charge  37  pushes the twine  32  ahead of it. When the front of charge  37  reaches end wall  34  it has wrapped bale twine  32  around the bottom front and top of the charge  37 . When the recompressed bale  37 , as shown in FIG. 2, is in a fully compressed state, needle activation device  23  activates to swing needles  20 , attached to needle yoke  22 , by means of needle arms  21 , up through slots  30  in bottom slide plate  26 .  
         [0029]    As is shown in FIG. 8, slots  31  are provided in recompression plates  15  so as to permit travel of needles  20  from slots  30  in the bottom slide plate up to needle opening  44  in top plate  36 . Needles  20  in the process of sliding upward through slots  30  and bottom slide plate  26 , carry with them bale twine  32 . When needles  20  are fully extended, as is shown in FIG. 2, they engage conventional knotters  19  which operate to: tie knots in the twine which has been wrapped around the recompressed bale; to cut the twine; and to retain the bitter end of the cut twine  32  which is threaded through needles  20 , as needles  20  are retracted by needle activation device  23 . Also envisioned is the use of a standard bale strapping means, or any means of tying the bale.  
         [0030]    In another embodiment, the means of tying the recompressed bale is a standard plastic strapping system which applies plastic straps to the recompressed bales. Other means of tying are also envisioned, including, but not limited to, baling wires.  
         [0031]    The end preferred length of a recompressed charge  37  is approximately 28 inches long, thus, the charge  37  is recompressed from 55 to 65 inches down to ˜28 inches in length. To arrive at this 28 inch length, the charge  37  must additionally be overcompressed 6 to 10 inches (down to roughly 19 inches long) in order for the wrapping means to operate to tie the charge  37 . After the wrapping means ties the charge, the charge  37  is allowed to expand back out to the ˜28 inch length. Thus, this overcompression is between 21% and 36% of the length of the end product. This degree of overcompression, however, only needs roughly 550 pounds per square inch of pressure at the plunger head—in comparison to the ˜1200 pounds needed for the prior art method. The preferred resulting recompressed bale or charge has approximate measurements of 16″×12″×28″ (or 16″×18″×28″, depending on the wishes of the operator), with a weight of approximately 80 pounds (or 120 pounds for the 18″ version), and a density of on average 27 pounds per cubic food. However, these measurements will vary depending on the fibrous material recompressed.  
         [0032]    The desired density range for the export bale market is 23 to 28 pounds per cubic foot. From experimentation, the inventor has been able to use the invented method to produce bales in the desired density range (23-28 pounds per cubic foot) through using between 400 and 625 pounds per square inch of pressure on the plunger head (recompression plate). Compared to the prior art method, which must use between 800 and 1350 pounds per square inch of pressure on the plunger head to achieve the same density, the inventor is very pleased with the performance of the present invention.  
         [0033]    Because the overcompression in this method is between 21% and 36% (remembering that the overcompression in the prior art method was 27% to 46%), less force is required at the recompression plate(s)  15 . While the prior art method typically requires a 450 hp engine to exert the required 800-1300 pounds per square inch of force at the plunger head, with the invented method, a 225 hp engine can easily be used because the required pounds of force is reduced to ˜550 pounds per square inch at the plunger head, a savings of at least one-half.  
         [0034]    Referring to FIG. 4, once bale  37  has been tied, and the twine  32  cut, with the bitter end retained by knotters  19 , and the needles  20  withdrawn, and prior to withdrawal of recompression platen  15 , ejection ram  17  is activated so that ejection platen  18  pushes recompressed bale  37  into decompression chamber  14 . As is shown in FIG. 3, the end of recompression platen  15  is aligned with the decompression chamber front plate  35  so that recompressed bale  37  will slide into decompression chamber  14  while remaining in a fully compressed state.  
         [0035]    Next referring to FIGS. 3, 4,  5 , and  6 , operation of the recompression apparatus  10  utilizing decompression chamber  14  is shown to advantage. First referring to FIG. 3, it is shown that recompressed charge  37 , is pushed into decompression chamber  14  only far enough to define a defacto bottom plate for recompression chamber  13 . In FIG. 4, a second charge  38  is being recompressed. In FIG. 5, the second recompressed charge  38  is pushed by ejection platen  18  into decompression chamber  14 , thereby pushing or displacing the first recompressed charge  37  down into the second position of decompression chamber  14 .  
         [0036]    When a third charge  39 , as is shown in FIG. 6, is recompressed and pushed into decompression chamber  14 , first charge  37  is ejected by the displacement action in decompression chamber  14 . As can be seen, first charge  37 , and each charge thereafter remains in the decompression chamber  14  for two full cycles of recompression operation by recompression apparatus  10 . The result is that each recompressed charge is held long enough for trapped air to escape and for the fibrous material to loose some of its resiliency prior to the time the bale twine  32  is subjected to the full recoil, expansion stress of a recompressed charge.  
         [0037]    While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto but may be variously embodied to practice within the scope of the following claims.