Abstract:
A refrigerated cargo container includes a refrigeration unit and a cargo container. The refrigeration unit includes a support frame formed from at least one layer of composite material and at least one layer of insulative foam material. The support frame is supportive of one or more components of the refrigeration unit and insulative of a cargo portion of the cargo container.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The subject matter disclosed herein relates to transportation refrigeration systems. More specifically, the subject matter disclosed herein relates to support structures for transportation refrigeration systems. 
         [0002]    Transportation refrigeration systems, such as those for refrigerated shipping containers typically include an insulated support frame to support and contain the components of the refrigeration system such as a compressor, condenser, evaporator, fan and other refrigeration system components. The support frame is typically formed from multiple aluminum sheets and extrusions, which are assembled by welding and riveting, then sealed. Insulating foam is injected between front an rear aluminum panels of the support frame. The aluminum frame is susceptible to corrosion, especially when used in overseas shipping containers. Further, the manufacture and assembly of the aluminum frame is costly and is also heavy which adds to costs of utilizing the container. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0003]    In one embodiment, a refrigerated cargo container includes a refrigeration unit and a cargo container. The refrigeration unit includes a support frame formed from at least one layer of composite material and at least one layer of insulative foam material. The support frame is supportive of one or more components of the refrigeration unit and insulative of a cargo portion of the cargo container. 
         [0004]    In another embodiment, a support frame for a refrigeration unit of a refrigerated cargo container includes one or more layers of composite material and at least one layer of thermally insulative material secured thereto. The support frame is supportive of one or more components of the refrigeration unit and is thermally insulative of a cargo portion of the cargo container. 
         [0005]    These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0007]      FIG. 1  is a schematic of an embodiment of a refrigerated cargo container; 
           [0008]      FIG. 2  is a schematic view of an embodiment of a refrigeration system for a cargo container refrigeration unit; 
           [0009]      FIG. 3  is a schematic view of an embodiment of a frame support for a cargo container refrigeration unit; 
           [0010]      FIG. 4  is a schematic view of another embodiment of a frame support for a cargo container refrigeration unit; 
           [0011]      FIG. 5  is a schematic of yet another embodiment of a frame support for a cargo container refrigeration unit; and 
           [0012]      FIG. 6  is a schematic view of still another embodiment of a frame support for a cargo container refrigeration unit. 
       
    
    
       [0013]    The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawing. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    Shown in  FIG. 1  is an embodiment of a refrigerated cargo container  10 . The cargo container  10  is configured to maintain a cargo  12  located inside the cargo container  10  at a selected temperature through the use of a refrigeration unit  14  located at the container  10 . The cargo container  10  is utilized to transport the cargo  12  via, for example, a truck, a train or a ship. The refrigeration unit  14  includes a compressor  16 , a condenser  18 , an expansion valve  20 , an evaporator  22  and an evaporator fan (not shown) located at, for example, a first end  26  of the container  10 . 
         [0015]    Referring to  FIG. 2 , the first end  26  comprises a frame  28 . The frame  28  separates a cargo portion  30  of the container  10  from the refrigeration unit  14  and insulates the cargo portion  30 . In some embodiments, the components of the refrigeration unit  14 , such as the compressor  16 , condenser  18 , expansion valve  20 , evaporator  22  and evaporator fan  24 , as well as any connecting tubing or piping and any additional components (not shown) are located at and secured to the frame  28 . In some embodiments, the frame  28  includes a recessed pocket  32  in which some components of the refrigeration unit  14  is located and secured. The frame  28  is configured to support the refrigeration unit  14  and to carry substantial loads of the container  10  such as racking and end loads. 
         [0016]    Referring to  FIG. 3 , the frame  28  is a molded composite structure including outer skin  34  and inner skin  36  formed from, for example, fiber reinforced polymer matrix composite (FRPMC) material. A layer of insulation  40 , such as a foam insulation, is disposed between the outer skin  34  and inner skin  36 . In some embodiments, the insulation  40  is pre-manufactured and formed to a selected shape and integrated into the frame  28  structure by a composite manufacturing process such as vacuum infusion (VI), resin transfer molding (RTM), lite resin transfer molding (LRTM), or the like. As such, the outer skin  34 , inner skin  36  and insulation are co-cured. Alternatively, the outer skin  34  and the inner skin  36  are pre-manufactured with sheet molding compound (SMC) and compression molding and assembled. The insulation  40  is then installed by, for example, injection of the insulation  40  as a foam. 
         [0017]    Referring now to  FIG. 4 , the frame  28  may include a stiffener  42  formed from a metal, such as aluminum or an alloy thereof to provide additional stiffness to the frame  28  structure if necessary or desired, especially in areas such as a perimeter of the frame  28 . To incorporate the stiffener  42  into the frame  28  structure, the stiffener  42  may be bonded into the frame  28  in a composite frame cure cycle. Alternatively, the stiffener  42  may be assembled to the completed outer skin  34 , inner skin  36  and insulation structure  40 , either by bonding with adhesives and/or with mechanical fasteners such as bolts (not shown). 
         [0018]    Referring to the embodiment shown in  FIG. 5 , the stiffener  42  is located in the frame  28  between the inner skin  36  and the outer skin  34 . The stiffener  42 , inner skin  36  and outer skin  34  are secured by, for example, bonding. Foam insulation  40  is then injected between the layers of the frame  28 . 
         [0019]    In another embodiment, shown in  FIG. 6 , the stiffener  42  is formed by stamping, welding or other suitable means, then pre-formed frame panels  44  are secured to the stiffener  42 . The frame panels  44 , as in other embodiments, include an outer skin  34  and inner skin  36 , with a layer of insulation  40  between the outer skin  34  and the inner skin  36 . 
         [0020]    The composite frame  28  structure secures the components of the refrigeration system  14 , while also carrying loads and providing insulation of the cargo portion  30  of the container  10 , while reducing weight and being less susceptible to corrosion. 
         [0021]    While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.