Abstract:
A temperature controlled container comprises exterior wall structure, interior wall structure positioned within the exterior wall structure, the interior wall structure at least partially defining an interior space configured to hold one or more products for shipping, and a chamber defined between the interior and exterior wall structure, the chamber configured to retain thermal storage medium to provide a thermally insulative layer at least partially protecting the interior space.

Description:
FIELD 
       [0001]    The subject application relates to containers and in particular to a temperature controlled container. 
       BACKGROUND 
       [0002]    It is common to ship products over vast distances by ground, sea and/or air transportation. In many instances, the products being shipped are placed in containers. When the products are not temperature-sensitive, there is typically no need to provide the containers with temperature control systems. When the products are temperature-sensitive, it is necessary to provide the containers with temperature control systems so that the internal temperature of the containers can be controlled thereby to avoid product spoiling due to low or high temperatures. As a result, refrigerated or heated containers are often used to maintain a substantially uniform and constant temperature throughout the interior of the containers in order to avoid spoilage. Many designs for temperature controlled containers have been considered. 
         [0003]    For example, U.S. Patent Application Publication No. 2009/0293524 to Vezina et al. discloses a method and apparatus for protecting temperature sensitive products during air, ground, or sea transportation. Specific embodiments relate to a chamber built inside a trailer or sea container where temperature sensitive products are placed to have additional protection against the environmental conditions encountered during the transportation and distribution periods. The dimensions and modularity of the chamber can vary depending on the trailer or sea container the chamber is designed to be used with. The chamber can be preassembled and inserted into the desired trailer or sea container or can be assembled inside the trailer or sea container. The chamber can include insulated and or non-insulated walls, a conveyor system, a ventilation system and temperature and asset (trailer or sea container) location tracking. The location tracking can utilize, for example, cellular (GSM) and/or satellite communication, with or without GPS tracking. Each wall of the chamber can be composed of a single material or a combination of dissimilar materials. One or more of the materials in the wall can possess insulating and/or phase changing properties. Different layers of the wall may incorporate different materials. 
         [0004]    U.S. Pat. No. 4,422,305 to Grosskopf discloses a cold storage element containing an eutectic brine cooled to a given freezing point by one or more refrigerant-conducting pipelines, the element being arranged interiorly of the body structure of a refrigerating vehicle. The cold storage element comprises a plastics material shell which has a rectangular configuration and a longitudinal rib interconnecting the opposing sidewalls. The pipeline for the refrigerant passes in a hair-pin configuration through both an upper compartment and a lower compartment defined by the longitudinal rib. Mounting assemblies and air control slats for the cold storage element are also provided. 
         [0005]    Although temperature controlled containers have been considered, improvements are desired. It is therefore an object to provide a novel temperature controlled container. 
       SUMMARY 
       [0006]    Accordingly, in one aspect there is provided a temperature controlled container, comprising exterior wall structure, interior wall structure positioned within the exterior wall structure, the interior wall structure at least partially defining an interior space configured to hold one or more products for shipping, and a chamber defined between the interior and exterior wall structure, the chamber configured to retain thermal storage medium to provide a thermally insulative layer at least partially protecting the interior space. 
         [0007]    In an embodiment the thermal storage medium is held in a confined space within the chamber. The confined space at least partially extends throughout the chamber. In an embodiment, the thermal storage medium is a cooling medium in the form of ice slurry. In another embodiment, the thermal storage medium is a heating medium in the form of glycol. 
         [0008]    According to another aspect there is provided a method of retro-fitting a conventional container having exterior wall structure, the method comprising installing interior wall structure within the conventional container, the interior wall structure positioned such that at least a portion of the interior wall structure is in a generally parallel-spaced relationship with at least a portion of the exterior wall structure, thereby defining a chamber, and at least partially filling the chamber with thermal storage medium. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Embodiments will now be described more fully with reference to the accompanying drawings in which: 
           [0010]      FIG. 1  is an isometric view of a temperature controlled container; 
           [0011]      FIG. 2  is a cross-sectional view of the temperature controlled container of  FIG. 2 ; 
           [0012]      FIG. 3  is a rear view of the temperature controlled container of  FIG. 1 ; 
           [0013]      FIG. 4  is a rear view of another embodiment of a temperature controlled container; 
           [0014]      FIG. 5  is a cross-sectional view of another embodiment of a temperature controlled container; 
           [0015]      FIGS. 6A and 6B  are rear and cross-sectional views, respectively, of another embodiment of a temperature controlled container; and 
           [0016]      FIG. 7  is an isometric view of another embodiment of a temperature controlled container. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0017]    Turning now to  FIGS. 1 to 3  a temperature controlled container is shown and is generally identified by reference numeral  10 . The container  10  is used to ship one or more temperature sensitive products by ground, sea and/or air transportation. For example, to ship products by ground transportation, the container  10  is configured to be placed on a semi-trailer. To ship products by sea transportation, the container  10  is configured to be placed on a cargo ship. To ship products by air transportation, the container  10  is configured to be placed on a cargo airplane. 
         [0018]    The container  10  comprises exterior wall structure  100  and interior wall structure  200  positioned within the exterior wall structure  100 . A space between the exterior wall structure  100  and interior wall structure  200  defines a chamber  300  for holding a thermal storage medium. A drainage member  350  is coupled to the chamber and is configured to permit the egress of thermal storage medium from the chamber  300 . An interior space  400  for holding one or more temperature sensitive products is defined by the interior wall structure  200 . 
         [0019]    The exterior wall structure  100  comprises a floor  120 , a ceiling  130  and two spaced apart side walls  140   a  and  140   b  extending between a front wall  150  and a rear wall  160 . The rear wall  160  comprises a door  170  such as for example a swing-type trailer door or a roll-type trailer door. 
         [0020]    The interior wall structure  200  is made of a rigid material and is positioned within the exterior wall structure  100 . In this embodiment, the interior wall structure  200  comprises side walls  210   a  and  210   b  and a top wall  220 . Each of the side walls  210   a  and  210   b  is positioned in a substantially parallel-spaced relationship with respect to a respective side wall  140   a  and  140   b  of the exterior wall structure  100 . The top wall  220  extends between the side walls  210   a  and  210   b  and is positioned in a substantially parallel-spaced relationship with respect to the ceiling  130  of the exterior wall structure  100 . 
         [0021]    The chamber  300  is defined between the ceiling  130  and side walls  140   a ,  140   b  of the exterior wall structure  100  and the top wall  220  and side walls  210   a ,  210   b  of the interior wall structure  200 , respectively. 
         [0022]    The draining member  350  is positioned at the bottom of the chamber  300 . In this embodiment, the draining member  350  comprises a mesh filter  360  positioned above a basin  370 . The mesh filter  360  is configured to drain any liquid material forming part of the thermal storage medium from the chamber  300  to the basin  370 , as will be described. 
         [0023]    The interior space  400  is defined between floor  120 , front wall  150  and rear wall  160  of the container  100  and the top wall  220  and side walls  210   a ,  210   b  of the interior wall structure  200 . The interior space  400  holds one or more temperature sensitive products for transport. 
         [0024]    In this embodiment, a thermal storage medium in the form of ice slurry is injected into the chamber  300  via an external piping system (not shown). The ice slurry creates an igloo-like effect around interior space  400 , thereby maintaining a generally uniform temperature within the interior space  400  for a period of time. As such, during shipping or storage operations within the period of time, any product placed within the interior space  400  will not spoil due to extreme high or low temperatures. Over time, as the ice slurry melts, any resultant liquid drains through the mesh filter  360  and into the basin  370 . As desired, the liquid may be disposed of or recycled for future use. As will be appreciated, varying the composition of the thermal storage medium varies the temperature of the interior space  400 . 
         [0025]    Turning now to  FIG. 4 , another embodiment of a container is shown and is identified by reference numeral  20 . In this embodiment, like reference numerals will be used to indicate like components. As can be seen, the container  20  is similar to container  10  with the addition of an insulation layer  500 . In this embodiment, the insulation layer  500  comprises three (3) vacuum insulated panels (VIP)  510   a ,  510   b  and  510   c  positioned interior of a respective one of the side walls  140   a  and  140   b  and ceiling  130  of the exterior wall structure  100 . In this embodiment, the chamber  300  is defined between the VIPs  510   a  to  510   c  and the top wall  220  and side walls  210   a ,  210   b  of the interior wall structure  200 . The container  20  may also comprise the draining member  350  shown in  FIG. 3 . 
         [0026]    Turning now to  FIG. 5 , another embodiment of a container is shown and is identified by reference numeral  30 . In this embodiment, like reference numerals will be used to indicate like components. As can be seen, container  30  is similar to container  10  with the exception of the side walls. As shown in  FIG. 5 , side wall  210   b  supports a plurality of collectors  600  which in this embodiment are generally U-shaped. The collectors  600  are dispersed about the exterior planar surface of side wall  210   b  and extend into the chamber  300 . In this embodiment, the collectors  600  are made of a rigid material. The collectors  600  support the thermal storage medium contained within the chamber  300  to ensure large portions of the side walls  210   a  and  210   b  are not left without thermal storage medium. For example, in the event that the thermal storage medium is ice slurry, the collectors  600  support portions of the ice slurry as it melts. Container  30  may also comprise the draining member  350  shown in  FIG. 3 . It will be appreciated that the collectors  600  may additionally or alternatively be positioned on the interior planar surface of the side walls  140   a  and  140   b  of the exterior wall structure  100 . 
         [0027]    Turning now to  FIGS. 6 a  and 6 b   , another embodiment of a container is shown and is identified by reference numeral  40 . In this embodiment, like reference numerals will be used to indicate like components. Container  40  is generally similar to that of container  10 , with the following exceptions. In this embodiment, interior wall structure  650  comprises side walls  660   a  and  660   b , a top wall  670  and a front wall  680 . Each of the side walls  660   a  and  660   b  is positioned in a substantially parallel-spaced relationship with respect to a respective side wall  140   a  and  140   b  of the exterior wall structure  100 . The top wall  670  extends between the side walls  660   a  and  660   b  and is positioned in a substantially parallel-spaced relationship with respect to the ceiling  130  of the exterior wall structure  100 . The front wall  680  extends front the top wall  670  to the floor  120  and is positioned in a substantially parallel-spaced relationship with respect to the front wall  150  of the exterior wall structure  100 . The interior wall structure  650  is made of a generally rigid and thermally conductive material. 
         [0028]    The thermal storage medium is held within a constricted space in the chamber  300 . In this embodiment, the constricted space is defined by a piping system  700 . The piping system  700  is thermally coupled to the interior wall structure  6500 . The piping system  700  comprises a plurality of pipes  705 , in this embodiment six (6), each of which comprises an inlet  710 , an outlet  720  and a pipe body  730  extending therebetween. The inlet  710  is positioned adjacent to the rear wall  160  of the exterior wall structure  100 . As shown in  FIG. 6 b   , the pipe body  730  extends generally parallel to the ceiling  130  towards the front wall  150  of the exterior wall structure  100 . The pipe body  730  bends at a right angle at a position adjacent to the front wall  150  and extends at an angle towards the floor  120  and towards one of the side walls  140   a  and  140   b  of the exterior wall structure  100 . The pipe body  730  bends at a right angle at a position adjacent to the intersection of the front wall  150  and the floor  120 . The pipe body  730  continues back towards rear wall  160  of the exterior wall structure  100  within the chamber  300 . The pipe body  730  ends at the outlet  720  which is positioned adjacent to intersection of the floor  120  and the rear wall  160  of the exterior wall structure  100 . 
         [0029]    In this embodiment, a thermal storage medium in the form of ice slurry is pumped into the inlet  710  of each one of the pipes  705  via a pumping unit (not shown). The ice slurry is pumped until each pipe body  730  is full of ice slurry. As each of the pipes  705  is thermally coupled to the interior wall structure  650 , thermal energy is exchanged therebetween. As the interior wall structure  650  surrounds the interior space  400 , a generally uniform temperature is maintained within the interior space  400  for a period of time. During shipping or storage operations within the period of time, any product placed within the interior space  400  will not spoil due to extreme high or low temperatures. In this embodiment, the ice slurry contained in each of the pipes  705  may be removed by pumping air through the inlet  710 , forcing the ice slurry out of the outlet  720 . Alternatively, the pipes  705  may be readily refilled by pumping new ice slurry into the pipes  705  via the inlet  710 , forcing old or melted ice slurry out of the pipes  705  via the outlet  710 . The pipes  705  may also be drained using gravity. As will be appreciated, varying the composition of thermal storage medium varies the temperature of the interior space  400 . 
         [0030]    Turning now to  FIG. 7 , another embodiment of a container is shown and is generally identified by reference numeral  50 . In this embodiment, like reference numerals will be used to indicate like components. As can be seen, container  50  is similar to container  40  with the exception that the piping system  700  comprises two (2) pipes  705 . In this embodiment, the inlet  710  and outlet  720  of each of the pipes  705  extends through the rear wall  160  of the container  100  such that they are accessible from outside of the interior space  400 . The pipe body  730  of each of the pipes  705  extends about the chamber  300  adjacent to one of the side walls  140   a  and  140   b  to define a serpentine channel configured to direct the ingress of thermal storage medium received via the inlet  710 . During use the inlet  710  and outlet  720  of each pipe  705  are each sealed with a removable cap (not shown). 
         [0031]    In this embodiment, a thermal storage medium in the form of ice slurry is pumped into the inlet  710  of each one of the pipes  705  via a pumping unit. The ice slurry travels around the serpentine channel defined by the pipe body  730 . Once each pipe  705  is fully of ice slurry, the inlet  710  and  720  are each sealed with a removable cap. As each of the pipes  705  is thermally coupled to the interior wall structure  200 , the pipes  705  transfer thermal energy to the interior wall structure  200  thereby maintaining a generally uniform temperature is within the interior space  400 , as described above. The ice slurry contained in each of the pipes  705  may be removed or the pipes may be refilled with new ice slurry as described above. 
         [0032]    In another embodiment, the constricted space may be defined by a removable conductive structure having a chamber defined therewith. In this embodiment, the chamber within the removable conductive structure may be filled with a thermal storage medium and then placed inside the container using a track system. In another embodiment, the removable conductive structure may have compartments defined therein to ensure thermal storage medium is dispersed throughout. In another embodiment, the removable conductive structure may be collapsible such that it can be collapsed when not in use. 
         [0033]    Those skilled in the art will appreciate that conventional containers may be retro-fit to be a temperature controlled container such as that described in any of the above embodiments. To retro-fit a conventional container, interior wall structure, such as that described above, is installed in the conventional container such that the interior wall structure is in a parallel-spaced relationship with the wall structure of the conventional trailer, thereby defining a chamber. The chamber may then be filled with thermal storage medium in a manner described in any of the above embodiments. 
         [0034]    Although in some embodiments above the side walls of the interior wall structure are described as being made of a rigid material, those skilled in the art will appreciate that the side walls of the interior wall structure may be made of a rigid, thermally conductive material. 
         [0035]    In some embodiments above the system is described as utilizing an insulation layer. Those skilled in the art will appreciate that any of the above described embodiments may utilize an insulation layer. 
         [0036]    Although in embodiments above the insulation layer is described of being made of a plurality of VIPs, those skilled in the art will appreciate that other types of insulation may be used. 
         [0037]    Although in embodiments above the thermal storage medium is described as being ice slurry, those skilled in the art will appreciate that alternative types of thermal storage medium may be used. For example, in another embodiment, a heating liquid such as for example glycol may be used or a phase change material such as a paraffinic wax. 
         [0038]    In another embodiment, an air gap may be defined intermediate the container side walls and ceiling and the interior wall structure (or intermediate the insulation layer and the interior wall structure) and a fan unit may be provided to circulate air that is heated/cooled by the thermal storage medium positioned within the chamber or contained within the piping system. 
         [0039]    Although in embodiments above the collectors are described as being generally U-shaped, those skilled in the art that alternatives are available. For example, in another embodiment the collectors may be V-shaped or may be generally flat. Alternatively, the collectors may be obstacles in the form of circles, triangles, squares, diamonds, etc. In another embodiment, the collectors may be provided with a mesh bottom, such that any solid material forming part of the thermal storage medium will be retained by the collectors, and any liquid material forming part of the thermal storage medium will be drained through the mesh bottom. 
         [0040]    Although in embodiments above the collectors are described as being made of a rigid material, those skilled in the art will appreciate that the collectors may be made of a rigid, thermally conductive material. 
         [0041]    Although in embodiments above the rear wall is described as being provided with a door such as for example a swing-type trailer door or a roll-type trailer door, those skilled in the art will appreciate that alternative types of doors may be used. For example, in another embodiment the door may be provided with an insulation layer. 
         [0042]    Although in embodiments above the system is described as comprising a draining member comprising a mesh filter positioned above a basin, those skilled in the art will appreciate that variations are available. For example, in an embodiment, the basin may comprise a draining opening configured to drain liquid out of the container. As will be appreciated, in this embodiment, the liquid may drain out of the container during travel. In another embodiment, the draining member may only comprise a basin, that is, the draining member may not have a mesh filter. In another embodiment, the basin may be positioned exterior of the container such that liquid may drain out of the container and into the basin. 
         [0043]    Although embodiments have been described above with reference to the accompanying drawings, those of skill in the art will appreciate that variations and modifications may be made without departing from the scope thereof as defined by the appended claims.