Patent Publication Number: US-2007119850-A1

Title: Composite dumpster

Description:
FIELD OF THE DISCLOSURE  
      The present disclosure relates generally to dumpsters.  
     BACKGROUND OF THE DISCLOSURE  
      Dumpsters are used to store waste material. For example, there are municipal waste dumpsters used to store municipal waste and which can be loaded onto and off of a vehicle for transporting the dumpster between a waste collection site and a landfill or other location.  
     SUMMARY OF THE DISCLOSURE  
      According to an aspect of the present disclosure, there is provided a dumpster that comprises a relatively high strength-to-weight fiber-reinforced composite material. Exemplarily, the dumpster comprises a metallic frame and a plurality of fiber-reinforced polymer panels secured to the metallic frame to define an interior waste storage volume for storing waste in the dumpster.  
      Illustratively, according to another aspect of the disclosure, the dumpster comprises opposed first and second side walls, first and second end walls interconnecting the first and second side walls at opposite longitudinal ends of the dumpster, and a floor to which the first and second side walls and the first and second end walls are secured. The first and second side walls, the first and second end walls, and the floor cooperate to define the interior waste storage volume. Further, the first end wall comprises a door pivotably mounted at the top thereof for discharge of waste from the interior waste storage volume. Exemplarily, each of the first side wall, the second side wall, the first end wall, the second end wall, and the floor comprises at least one of the fiber-reinforced polymer panels.  
      The above and other features of the present disclosure will become apparent from the following description and the attached drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of a composite dumpster;  
       FIG. 2  is a fragmentary perspective of the dumpster;  
       FIG. 3  is a side elevation view showing tilting of the dumpster to empty waste therefrom upon opening of a door;  
       FIG. 4  is a fragmentary end elevational view of a first end of the dumpster showing a U-shaped gasket which is viewable in the absence of a door of the first end;  
       FIG. 5  is a sectional view taken along lines  5 - 5  of  FIG. 4 ;  
       FIG. 6  is a sectional view taken along lines  6 - 6  of  FIG. 4 ;  
       FIG. 7  is an end elevational view of a second end of the dumpster opposite to the first end; and  
       FIG. 8  is a bottom view of the dumpster. 
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS  
      While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific exemplary embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that there is no intent to limit the disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives following within the spirit and scope of the invention as defined by the appended claims.  
      Referring to  FIGS. 1-3 , there is shown a composite dumpster  10 . The dumpster is made of a fiber-reinforced composite material so that the dumpster  10  has a relatively high strength-to-weight ratio. As such, the dumpster  10  is useful for storing all sorts of waste materials including, but not limited to, municipal solid waste in an interior waste storage volume  12  defined in the dumpster  10 . For example, the dumpster  10  may be placed at or near a work site or other waste collection site for temporary storage of waste material as needed. When the dumpster  10  is full or it is otherwise time to remove the dumpster  10 , the dumpster  10  can be loaded onto a vehicle and transported to a landfill or other location where the dumpster  10  can be emptied of its contents ( FIG. 3 ). The dumpster  10  can then be transported to the same or another site and unloaded from the vehicle for re-use. Use of the fiber-reinforced composite material in the dumpster  10  not only promotes a relatively high strength-to-weight ratio for the dumpster  10 , it also promotes the longevity of the useful life of the dumpster  10 .  
      The fiber-reinforced composite material may be embodied in a variety of ways. For example, the material may be embodied as a fiber-reinforced polymer (FRP) having a reinforcing agent in a polymer resin matrix. The FRP material may be embodied as any FRP structure including, but not limited to, a solid laminate or a sandwich panel (e.g., a panel having first and second skins with a core sandwiched therebetween and possibly fiber insertions extending from the first skin through the core to the second skin). As such, the FRP structures may be embodied, for example, as either 2-D or 3-D structures (e.g., a 2-D or 3-D laminate or panel). An exemplary sandwich panel for use in the dumpster  10  is TRANSONITE® available from Martin Marietta Materials, Inc. of Raleigh, N.C.  
      The matrix may include a thermosetting resin, although thermoplastic resins are also contemplated for use. Examples of thermosetting resins which may be used include, but are not limited to, unsaturated polyesters, vinyl esters, polyurethanes, epoxies, phenolics, and mixtures and blends thereof.  
      The reinforcing agent may include E-glass fibers, although other reinforcements such as S-glass, carbon, KEVLAR®, aramids, metal, UHMW (ultra high molecular weight) materials, high modulus organic fibers (e.g. aromatic polyamides, polybenzamidazoles, and aromatic polyimides), and other organic fibers (e.g. polyethylene and nylon) may be used. Blends and hybrids of the various reinforcing materials may be used. Other suitable composite materials may be utilized including whiskers and fibers such as boron, aluminum silicate, and basalt.  
      In the case of where the FRP structure is embodied as a sandwich panel, the core type may include, but is not limited to, balsa wood, foam, open-cell material, closed-cell material, and various types of honeycomb.  
      The FRP structures may be embodied as any of the structures disclosed in U.S. Pat. Nos. 5,794,402; 6,023,806; 6,044,607; 6,070,378; 6,081,955; 6,108,998; 6,467,118 B2; 6,645,333; 6,676,785, the entirety of each of which is hereby incorporated by reference. It should be appreciated that the structures disclosed in the above-identified patents may be sized, scaled, dimensioned, orientated, or otherwise configured in any desired manner to fit the needs of a given design of the FRP structure.  
      Illustratively, the dumpster  10  is configured as an open top hollow rectangular box, although other geometric or irregular shapes are also contemplated (e.g., cubic or other polygonal shapes). In the illustrative rectangular box example, the dumpster  10  has opposed side walls  14 , a first end wall  16  interconnecting the side walls  14  at a first longitudinal end of the dumpster  10 , a second end wall  18  interconnecting the side walls  14  at an opposite second longitudinal end of the dumpster  10 , and a floor  20  to which the walls  14 ,  16 ,  18  are secured. The walls  14 ,  16 ,  18  and the floor  20  cooperate to define the interior waste storage volume  12 . In addition, the walls  14 ,  16 ,  18  cooperate to provide the dumpster  10  with a top opening  22  for reception of waste material into the volume  12 . The top opening  12  may be covered or uncovered.  
      Exemplarily, the dumpster  10  is about 20 feet long, about 8 feet wide, and about 12 feet high and weighs less than 10,000 pounds (4,536 kg). For example, the dumpster  10  weighs about 6300 pounds (2,858 kg). This is less than the weight of all-metal dumpsters weighing 10,500 pounds (4,763 kg) or, in some cases, 10,150 pounds (4,604 kg).  
      Further exemplarily, the dumpster  10  is constructed to satisfy ISO (International Organization for Standardization) 1496-1:1990(E) which is hereby incorporated by reference herein. Under a load of about 52,911 pounds (24,000 kg) (the load including the weight of both the dumpster  10  and cargo therein), a wall  14  of the dumpster  10  deflected only about 2 15/16inches (7.46 cm), within the ISO envelope. The wall  14  returned to its original state upon removal of the cargo. Each wall  14  is thus resiliently deflectable.  
      To provide the dumpster  10  with the thus-described shape or other shape, the dumpster  10  comprises a frame  24  and a number of FRP panels  26  secured thereto and sized according to their particular use and location within the dumpster  10 . The structural members of the frame  24  may all be metallic, may all be made of a fiber-reinforced composite material, or may be a mix of metallic and fiber-reinforced composite members. In the case where the frame  24  has at least one metallic structural member, the frame  24  may be referred to as a metallic frame, as in the illustrative example of the dumpster  24  which has a number of metallic structural members made of carbon steel or other metal.  
      In the illustrated embodiment, each side wall  14  is provided by a number of frame members and a number of panels  28 . In particular, exemplarily, each side wall  14  is provided by an upper horizontal longitudinal tubular beam  30 , a lower horizontal longitudinal channel  32 , a pair of vertical corner posts  34 , and joints  36  in the form of castings interconnecting the posts  34 , the beam  30 , and the channel  32 .  
      There are, for example, three panels  28   a ,  28   b ,  28   c  which form the main body of the wall  14 . The panels  28   a ,  28   b ,  28   c  are secured to the beam  30 , the channel  32 , and the posts  34  by use of additional frame members. For example, on the outside of the panels  28   a ,  28   b ,  28   c , there are a horizontal upper channel  38 , a pair of corner angle bars  40 , and a pair of vertical tubular bars  42 , and, on the inside of the panels  28   a ,  28   b ,  28   c , there are a number (e.g., three) of horizontal upper angle bars  44 , a horizontal lower angle bar  46 , and a pair of vertical T-shaped bars  48 . Each of the panels  28   a ,  28   b ,  28   c  of the wall  14  is secured to the upper channel  38 , the lower channel  32 , one of the upper angle bars  44 , and the lower angle bar  46 . The intermediate panel  28   b  is also secured to both tubular bars  42  and both T-shaped bars  48 , each of which extends between the intermediate panel  28   b  and an adjacent end panel  28   a ,  28   c . Each end panel  28   a ,  28   c  of the wall  14  is also secured to one of the tubular bars  42 , one of the T-shaped bars  48 , and one of the corner angle bars  40 . The panels  28   a ,  28   b ,  28   c  may be secured to their respective frame members by use of, for example, an adhesive or other bonding agent and/or one or more fasteners.  
      An access hole  50  may be formed in any of the panels  28   a ,  28   b ,  28   c  of the wall  14 , illustratively, the intermediate panel  28   b . The hole  50  may be closed with a plug  52  when not in use.  
      The first end wall  16  is provided, for example, by a number of the frame members and a door  54 . The frame members include a pair of posts  34  and horizontal upper and lower transverse tubular bars  56 ,  58  interconnecting the posts  34  via joints  36 . Gussets  59  may be secured to beams  30  and the bar  56 .  
      The door  54  is mounted at its top to the upper transverse bar  56  by hinges  60  for pivotable movement between a closed position shown in  FIGS. 1 and 2  and an opened position  FIG. 3 . The door  54  may be locked in the closed position by a lock mechanism including a first latch  62  mounted to the door  60  and a second latch  64  mounted to each panel  28   a . The door  54  includes a panel  28   d  secured to vertical tubular bars  66  and horizontal tubular bars  68 .  
      Referring to  FIGS. 4-6 , a deformable gasket  70  is provided to establish a sealed connection between it and the panel  28   d  upon closure of the door  54  to prevent leakage from volume  12 . Illustratively, the gasket  70  is generally U-shaped such that it has a pair of vertical portions  72  and a connecting horizontal portion  74 . Each vertical portion  72  is secured to a vertical plate  76  secured to a respective panel  28   a . The horizontal portion  74  is secured to the horizontal plate  78  secured to a panel  28   e  of the floor  20 . The gasket  70  is compressed (e.g., about 25%) when the door  54  is closed and returns to its relaxed state to assume a generally D-shaped configuration when the door  54  is opened. Exemplarily, the gasket  70  is made of medium density neoprene although other materials suitable for effecting the seal may be used.  
      Referring to  FIG. 7 , the second end wall  18  is provided, for example, by a number of frame members and a panel  28   f . Horizontal upper and lower transverse tubular bars  80 ,  82  are secured to corner posts  34  via joints  36 . The panel  28   f  is secured to these frame members by the use of additional frame members. On the outside, the panel  28   f  is secured to a horizontal upper channel  84  secured to the bar  80 , a horizontal lower angle bar  86  secured to the bar  82 , and a pair of vertical angle bars  88  secured to the posts  34 . As shown in  FIG. 2 , on the inside, the panel  28   f  is secured to a horizontal upper angle bar  90  secured to the bar  80 , a horizontal lower angle bar  92  secured to the bar  82 , and a pair of vertical corner angle bars  94  secured to the panel  28   f  and the respective panel  28   c . Additional gussets  59  may be secured to beams  30  and bar  80 .  
      Referring to  FIG. 8 , the floor  20  is provided, for example, by a number of frame members and the panel  28   e . Exemplarily, the panel  28   e  is one relatively large panel extending most of the length of the dumpster  10  although the panel  28   e  may be formed of a plurality of smaller panels. The panel  28   e  (or panels) are secured to the two longitudinal channels  32  and a plurality of transverse channels  94  secured to the channels  32 .  
      As for the materials of the frame members, as alluded to above, the frame members may be made of metal and/or a fiber-reinforced composite material. Exemplarily, all of the frame members are made of metal (e.g., steel) except frame members  46 ,  48 ,  92 , and  94 .  
      An exemplarily construction of each panel  28  is shown in  FIGS. 5 and 6  with reference to panels  28   a ,  28   d ,  28   e . The panel  28  is configured, for example, as a sandwich panel comprising first and second skins  96 ,  98 , a core  100  sandwiched between the skins  96 ,  98 , and a plurality of fiber insertions  102  extending from the first skin  96  through the core  100  to the second skin  98 . The skins  96 ,  98  are made, for example, of a glass-fiber-reinforced polyester resin polymer and the core  100  is made, for example, of urethane foam, although any of the reinforcing agents and matrix materials mentioned above can be used in the panel  28 .  
      While the concepts of the present disclosure have been illustrated and described in detail in the drawings and foregoing description, such illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.  
      There are a plurality of advantages of the concepts of the present disclosure arising from the various features of the systems described herein. It will be noted that alternative embodiments of each of the systems of the present disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of a system that incorporate one or more of the features of the present disclosure and fall within the spirit and scope of the invention as defined by the appended claims.