Abstract:
A method of forming a higher density bale of waste paper from two or more lower density bales of waste paper includes positioning the lower density bales intact and in side-by-side relationship with respect to each other, moving them to a compression zone, and compressing the bales together in the compression zone to form a higher density bale. The higher density bale can then be strapped to maintain its higher density configuration and shape. Thus, a larger tonnage of waste paper in bales can be loaded into a shipping container for transport. A rebaler for carrying out the method includes side feed and side retrieval of bales, significantly improving over traditional top feed machines.

Description:
TECHNICAL FIELD 
       [0001]    This disclosure relates generally to paper and more specifically to the baling of waste paper into bales for transport and handling. 
       BACKGROUND 
       [0002]    The recycling of old corrugated cardboard (OCC), OCC scrap, and other waste paper is ecologically responsible, cost effective, and more efficient than making of virgin cardboard and other paper. Currently, waste paper recycling supports a large and growing industry in the Unites States and elsewhere. Generally, OCC and waste paper is compacted into relatively compact bales and transported to recycling centers for processing. For example, a grocery or retail store may have a small paper baler on-site that it uses to compress empty cardboard boxes into bales that can be picked up and transported to a recycling center. Paper bales created at such on-site locations may typically weight around one thousand pounds each and are known in the industry as low density bales. 
         [0003]    Low density paper bales generally have been acceptable for transporting domestically from individual store locations to recycling centers and the like. However, markets for OCC and other scrap paper are growing rapidly in China and other countries. Transporting baled OCC and other waste paper internationally to these countries involves filling shipping containers with bales and transporting the containers abroad by container ship, which is expensive. A typical shipping container has a target weight capacity of between about 50,000 pounds and 60,000 pounds to obtain the most economical shipping cost per container. However, a container load of low density paper bales weighs significantly less than this target. Thus, it has been common to rebale these low density bales into higher density bales that meet the target weight when loaded into shipping containers to transporting abroad. It can also be more efficient to transport high density paper bales domestically since a higher tonnage can be transported on a single truck. 
         [0004]    Paper rebaling generally has been done at central locations such as retail distribution centers to which low density paper bales are back-hauled from individual stores, or at recycling centers. This is due in part to the fact that machines for rebaling paper from low density paper bales into high density paper bales have been large, very expensive, and relatively complex to operate. In a typical high density rebaler, low density bales are placed on a conveyor and the binding wires are cut by an operator to free the baled paper. The conveyor carries the unbound bales up to the inlet of a vertically fed hydraulic baling machine, where they fall from the end of the end of the conveyor into the hopper of the baling machine. In the process, the unbound bales fall apart and the loose paper drops into the breach of the baling machine. When the breach is full, a hydraulic compression ram driven by a main cylinder compresses the paper into a compression chamber to form a high density mass of paper. The ram may cycle two or three times in this manner until a sufficient mass of compressed paper is pressed into the compression chamber to comprise a high density bale. The resulting high density bale is then bound with wire or other bindings and ejected from the baler for storage and transport. The process is generally inefficient due at least partially to the multiple cycling of the ram per bale and the process is sufficiently complex that it generally must be monitored and controlled by computer controllers. In addition, at least two workers generally are required to load bales onto the conveyor and cut the bindings before the bales are conveyed to the hopper of the baling machine. 
         [0005]    There is a need for a waste paper rebaler for creating high density paper bales from lower density paper bales that is smaller, is fed from the side rather than the top, is simpler to operate, less expensive, and that does not require that the bindings of low density bales be removed or that the low density bales be unbound and their paper re-disbursed prior to the rebaling process. It is to the provision of such a rebaler and to a corresponding method of rebaling that the present disclosure is primarily directed. 
       SUMMARY 
       [0006]    Briefly described, a waste paper rebaler comprises a horizontally oriented rectangular housing defining an internal chamber having an upstream end and a downstream end. A breach is defined at the upstream end of the chamber. A feed port is formed in the side of the housing at the upstream end adjacent the breach and is sized to receive two low density paper bales in side-by-side relationship. A compression chamber is formed at the downstream end of the housing and has a size corresponding to that of a paper bale. A hydraulically driven compression cylinder extends through the upstream end of the housing and drives a rectangular compression plate or ram through the breach and toward the compression chamber. An ejection port is formed, again in the side of the housing at the compression chamber, and a hydraulically driven ejector cylinder extends through the housing on the opposite side of the compression chamber. The ejector cylinder drives a rectangular ejector ram through the compression chamber and toward the ejector port. Significantly, both the feed port and the ejector port are formed in the sides of the housing and are positioned to be accessible by a fork lift truck. 
         [0007]    In use, two low density paper bales, with wire bindings intact if desired, are loaded into the breach of the housing&#39;s internal chamber through the side loading feed port by a fork lift truck and operator. The machine is then activated, whereupon the compression ram pushes the two low density bales toward and progressively into the compression chamber and compresses the bales into a single high density bale. The high density bale may then be bound with bindings. The ejector ram then pushes the high density bale out of the compression chamber through the side mounted ejection port, from where they can then be moved by the fork lift operator to storage or staging locations. 
         [0008]    The waste paper rebaler of this disclosure has a small footprint, is substantially less expensive to fabricate and operate than traditional rebalers, can be operated by a single worker with a forklift without the need for computer controls, and is efficient due in part to the fact that only a single cycle rather than 3 or more as in the prior art is required to create each high-density bale. Further, the side loading and removal features of the rebaler significantly simplify the loading of low density bales and the unloading of high density bales as compared to traditional top-load conveyor style balers. These and other features, aspects, and advantages of the waste paper rebaler of this disclosure will become more apparent upon review of the detailed description set forth below taken in conjunction with the accompanying drawing figure, which is briefly described as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a perspective view of a waste paper rebaler that embodies principles of the invention in one preferred embodiment. 
           [0010]      FIG. 2  is a top plan view of the rebaler illustrating loading of low density bales and ejection of a high density bale. 
       
    
    
     DETAILED DESCRIPTION 
       [0011]    Referring now to the drawing figures, wherein like reference numerals indicate like parts throughout the views, a waste paper rebaler  11  is shown for compressing two (or more) low density waste paper bales into one high density waste paper bale. The invention may be described herein within the context of rebaling OCC, but the invention is not limited to OCC and any paper or other material (such as hay for example) may be recompressed into higher density bales with the rebaler disclosed herein. Further, the OCC need not necessarily be “old” or used, but can be industrial scrap, post consumer waste, or any other paper that can be baled and recycled. 
         [0012]    The rebaler  11  comprises a generally rectangular housing  12  having a top  13 , a bottom  14 , sides  10 , an upstream end  16 , and a downstream end  17 . The housing defines and internal chamber, also having an upstream end and a downstream end. A rectangular feed port  18  is formed in a side  10  of the housing adjacent the upstream end portion of the housing  12  and a smaller rectangular ejection port  19  is formed in the side  10  adjacent the downstream end portion of the housing. A loading platform  21  may be provided beneath and outboard of the feed port and a retrieval platform  23  may be located beneath and outboard of the ejection port  19 . Doors  22 , which may be closable with a hydraulic or mechanical closer (not shown) may be provided at the feed port for purposes described in more detail below. The ports and platforms provide for side loading and side retrieval of bales with fork lift or other transport device, which represents a great improvement over traditional balers having a conveyor that carries unbound bales up to be dumped into a top load hopper. A breach  20  of the rebaler  11  is formed within the upstream portion of the housing  12  adjacent the feed port  18 . Similarly, a compression chamber  15  is defined within the downstream portion of the housing  12  adjacent the ejection port  19 . 
         [0013]    A rectangular compression plate or ram  26  is, in a rest position, disposed at the upstream end of the housing  12 . The compression ram  26  is attached to the shaft of an extendable hydraulic cylinder  27  that extends through the upstream end of the housing  12 . The hydraulic cylinder  27  can be activated to drive the compression ram  26  in a downstream direction through the breach and toward the compression chamber  15  as indicated by arrow  28 . A rectangular ejection ram  31  is located at the downstream end portion  17  of the housing  12  and has a rest position against the side  10  of the housing opposite the ejection port  19 . The ejection ram  31  is connected to the shaft of a hydraulic cylinder  32  that extends through the side  10  of the housing and can be actuated to drive the ejection ram  31  toward the ejection port  19 , as indicated by arrow  33 . It will be understood by those of skill in the art that  FIG. 1  is a simplified drawing illustrating main components of the rebaler of this disclosure for clarity and ease of description. Of course, various supports, controls, power supplies, hydraulic reservoirs, pumps, etc. will be present, but are eliminated in the figures for clarity. Further, components may be configured differently than shown and some may be eliminated within the scope of the invention, only one embodiment of which is illustrated by the drawings. 
         [0014]      FIG. 2  is an overhead perspective that illustrates operation of the waste paper rebaler according to a preferred embodiment. An operator in a fork lift truck  36  retrieves low density paper bales from a remote location and delivers them to the feed platform  21  of the rebaler  11 . The feed platform  21  and the feed port  18  in the illustrated embodiment ( FIG. 1 ) are sized to accept two low density bales side-by-side. The operator may place a bale on the feed platform and then back up and push the bale into the breach  20  of the housing with the forks of the fork lift truck. In  FIG. 2 , one low density bale is shown positioned in the breach  20  while the operator is pushing the second low density bale into the breach with the fork lift truck, as indicated by arrows  41 . It will be clear from this figures that the side-loading feature of the rebaler represents a significant enhancement over traditional top loading balers. Once moved into the breach, the bales are positioned in side-by-side relationship with respect to each other. Of course, the bales may be loaded into the breach by other methods such as, for instance, with a conveyor, a hand truck, an overhead crane, with pneumatic doors that close behind the bales and push them into the breach, or with any other technique designed to move the bales into the breach in a side-by-side relationship. All and any such techniques should be considered to be within the scope of the invention. 
         [0015]    With the two low density bales positioned in the breach intact and, if desired, with their bindings still in place, the pneumatic cylinder  27  is activated. This drives the compression ram  26  in direction  28  through the breach and toward the compression chamber  15  at the downstream end of the housing  12 . When the bales reach the compression chamber, they engage an appropriate stop (not shown) at the downstream end of the housing, and the compression ram continues to advance. This causes the low density bales to begin to be compressed together into a smaller volume, thus increasing the density per unit volume of the combined bales. When the bales have been compressed to approximately the volume and size of a single bale, they may be strapped together in know ways so that they are held in their compressed condition by the straps. In this state, the volume and size of the combined bales is approximately the same as the volume of each low density bale before compression. Consequently, the density of the resulting bale is approximately twice the density and twice the weight of a low density bale, but about the same size. It is thus referred to as a high-density bale. 
         [0016]    With the high density bale created, the compression ram  26  can be retracted back to its ready position at the upstream end of the housing  12 . The hydraulic cylinder  32  is then activated to drive the ejection ram  31  in a transverse direction as indicated by arrow  33 . This pushes the high density bale out of the compression chamber  15 , through the side facing ejection port, and onto the retrieval platform  23 , from where it can be retrieved with a fork lift truck and moved to a storage location awaiting loading into a shipping container. It will be recognized by those of skill in the art that the above disclosed process is more efficient, faster, and effective than prior art waste paper rebaling techniques. It does not require that the low density bales be unbound and their paper re-disbursed, it completes the compression step each time with a single stroke of the compression ram, and delivers the resulting high density bale to a convenient location for retrieval. Further, the side loading and side retrieval of bales with the rebaler of this invention significantly improves over traditional top loading balers. As a result, the apparatus of this disclosure can be operated by a single operator with a fork lift truck to produce high-density bales at similar or likely higher rates than prior art rebalers, all with a reduced workforce. 
         [0017]    The invention has been described herein in terms of preferred embodiments and methodologies considered by the inventor to represent the best mode of carrying out the invention illustrated thereby. It will be understood by those of skill in the art, however, that a wide range of additions, deletions, and modifications, both subtle and gross, might well be made to the illustrated embodiment without departing from the spirit and scope of the invention, which is defined only by the claims.