Abstract:
A drum sectioner includes a plurality of wires extending between an upper chamber and a lower chamber. Electrical current through the wires causes the wires to become hot enough to melt/cut plastic. One ore more plastic drums placed in the upper chamber are sectioned by the hot wires without producing any shavings or dust. The drum is sectioned as it descends from the upper chamber to the lower chamber through the wires.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates generally to a drum sectioner.  
         [0002]     Plastic drums are sometimes used for shipping liquids. Some plastic drums that are used to ship beverages are not reused, but are shipped back empty to the supplier. The supplier grinds the plastic drum and recycles the plastic. The empty drums are somewhat burdensome to return, because of the volume that they occupy.  
         [0003]     A known machine uses a combination of band saws and rotating cutters to cut the plastic drums before returning them to the supplier. One band saw cuts the drum longitudinally (along the axis of symmetry of the drum) and two other band saws cut the top and bottom off the drum. This greatly reduces the volume occupied by the empty drum and the cost and effort in shipping it back to the supplier. However, the band saws generate plastic shavings and dust, which is undesirable.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention provides a drum sectioner which cuts an empty plastic drum into a plurality of pieces for return to the supplier, without any shavings or dust. The drum sectioner includes a plurality of hot wires that cut the empty plastic drum cleanly in up to six pieces, depending on the size.  
         [0005]     In a preferred embodiment, the drum sectioner includes a longitudinal wire aligned with the axis of symmetry of the drum and a pair of lateral wires positioned adjacent the top and bottom of the drum. The wires separate an upper chamber from a lower chamber in a sealed housing. One or more whole, empty drums are placed in the upper chamber on top of the wires. As electrical current is passed through the wires, the wires heat and begin to melt the drum. The hot wires cut through the drum as the drum begins to descend (e.g. by force of gravity) from the upper chamber to the lower chamber. The drum is sectioned into smaller pieces that are received in the lower chamber, without dust or shavings. The pieces can easily be shipped back to the supplier or to a recycler. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]     Other advantages of the present invention can be understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:  
         [0007]      FIG. 1  is a perspective view of a drum sectioner according to a first embodiment of the present invention with an empty drum being inserted.  
         [0008]      FIG. 2  is the drum sectioner of  FIG. 1 , with the drum in position for the cutting process to begin.  
         [0009]      FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 2 .  
         [0010]      FIG. 4  is a sectional view taken along line  4 - 4  of  FIG. 3 .  
         [0011]      FIG. 5  is a sectional view taken along line  5 - 5  of  FIG. 3 .  
         [0012]      FIG. 6  is a perspective view of a drum sectioner according to a second embodiment of the present invention.  
         [0013]      FIG. 7  is a schematic top view of the wires inside the drum sectioner of  FIG. 6 .  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0014]     A drum sectioner  10  for sectioning empty plastic drums  12  according to the present invention is shown in  FIG. 1 . The drum sectioner  10  includes a cabinet or housing  14  having upper doors  16  leading to an upper chamber  18  and lower doors  20  leading to a lower chamber  19 .  
         [0015]     A controller  22 , such as a CPU, FPGA, or hard-wired circuitry controls the drum sectioner  10  to perform the functions described herein. The controller  22  controls power supplied through a fused disconnect  24  and by transformers  26 ,  28 . The controller  22  also controls a fume cleaner  30  for removing any fumes generated in the drum sectioning process. An indicator light  32  indicates the status of the drum sectioning process.  
         [0016]      FIG. 2  shows the drum sectioner  10  after the drum  12  has been inserted into the upper chamber  18  and the upper doors  16  have been closed. When the drum  12  is inserted and the upper doors  16  and lower doors  20  have been latched, the controller  22  turns on the power supplies, including the transformers  26 ,  28 .  
         [0017]     Referring to  FIG. 3 , the transformers  26 ,  28  supply power to electrical connectors  40  that send electrical current through a longitudinal wire  42  and a pair of lateral wires  44 . The longitudinal wire  42  is generally aligned with the axis of symmetry of the drum  12 . The lateral wires  44  are aligned against a side wall  36  of the drum  12  and adjacent the upper and lower end walls  38  of the drum  12 . The longitudinal wire  42  and lateral wires  44  are positioned between the upper chamber  18  and the lower chamber  19  ( FIG. 2 ). The drum  12  rests on the wires  42 ,  44  when the drum is in the upper chamber  18 .  
         [0018]     When current is supplied to the wires  42 ,  44 , the wires  42 ,  44  achieve a high enough temperature to melt the plastic of the drum  12 . The weight of the drum  12  pushes the drum  12  through the wires  42 ,  44 , thereby cutting the drum  12  into sections.  
         [0019]     As shown in  FIG. 4 , with the cutting of the drum  12  in process, the lateral wires  44  are cutting through the side wall  36  of the drum  12  to separate the upper and lower ends  38  of the drum  12 . Referring to  FIG. 5 , the longitudinal wire  44  cuts the side wall  36  into two pieces and cuts each of the upper and lower ends  38  into two. The weight of the drum  12  forces the drum  12  slowly through the hot wires  42 ,  44 . Alternatively, the wires  42 ,  44  could move relative to the housing  14  or a device could push the drum  12  through the wires  42 ,  44 .  
         [0020]     When the drum  12  passes completely through the wires  42 ,  44 , the six pieces of the drum  12  drop into the lower chamber  19  of the drum sectioner  10  and can be removed through the lower doors  20  ( FIG. 2 ). Several drums  12  can be sectioned before emptying the lower chamber  19 .  
         [0021]     The hot wires  42 ,  44  cut the drum  12  into manageable pieces that can be shipped in less volume without producing plastic shavings or dust. The drum sectioner  12  is automated and requires very little effort by the user.  
         [0022]     A drum sectioner  110  according to a second embodiment is shown in  FIG. 6 . Elements of the drum sectioner  110  that are similar to those in the drum sectioner  10  of  FIGS. 1-5  are given identical reference numbers. The drum sectioner  110  is designed to section two drums  12  at once. Other drum sectioners that can section more than two at once could also be used and would be within the scope of the present invention. The drum sectioner  110  includes a larger housing  114  and an upper door  116  that pivots down. A template  160  slides in and out of the housing  114  through the open upper door  116 . The template  160  includes a plurality of openings  162  into which are received empty drums  12  (which are supported on the open upper door  116 . The template  160  may include handles  164  for facilitating sliding the template  160  and drums  12  in and out of the housing  114 . When the template  160  is pushed into the housing  114 , the drums  12  are each aligned with and supported on wires  42 ,  44  ( FIG. 7 ) as was the single drum  12  in the first embodiment.  
         [0023]      FIG. 7  is a schematic top view of the wires  42 ,  44  inside the drum sectioner  110  of  FIG. 6 . The drums  12  are shown in phantom to illustrate their alignment with the lateral wires  42  and the longitudinal wires  44  during operation. After the drums  12  are aligned with the wires  42 ,  44 , the wires are heated and the drums  12  are each sectioned as described above with respect to the first embodiment.  
         [0024]     While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. For example, the arrangement and number of wires  42 ,  44  could be changed.