Patent Publication Number: US-11378324-B2

Title: Modular cold boxes for transport refrigeration unit

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a 371 of International Application No. PCT/IB2015/002118, filed Oct. 22, 2015, which is incorporated by reference in its entirety herein. 
     BACKGROUND 
     The present disclosure relates to transport refrigeration units and, more particularly, to modular cold boxes for the transport refrigeration unit. 
     Traditional refrigerated cargo trucks or refrigerated tractor trailers, such as those utilized to transport cargo via sea, rail, or road, is a truck, trailer or cargo container, generally defining a cargo compartment, and modified to include a refrigeration system located at one end of the truck, trailer, or cargo container. Refrigeration systems typically include a compressor, a condenser, an expansion valve, and an evaporator serially connected by refrigerant lines in a closed refrigerant circuit in accord with known refrigerant vapor compression cycles. A power unit, such as a combustion engine, drives the compressor of the refrigeration unit, and may be diesel powered, natural gas powered, or another type of engine. In many tractor trailer transport refrigeration systems, the compressor is driven by the engine shaft either through a belt drive or by a mechanical shaft-to-shaft link. In other systems, the engine drives a generator that generates electrical power, which in-turn drives the compressor. 
     The refrigeration units typically cool the entire compartment defined by the cargo container. Opening and closing of container doors may lead to cooling inefficiency and reduced temperature control. Manufacturers and operators of fleets of refrigerated trucks, trailers and/or cargo containers desire to maximize operational efficiency and control of the entire cooling process. 
     SUMMARY 
     A transport containment assembly according to one, non-limiting, embodiment of the present disclosure includes a refrigeration unit; a container; and a plurality of boxes for storage of cargo and configured in series with one-another for the flow of cooling air from the refrigeration unit. 
     Additionally to the foregoing embodiment, each one of the plurality of boxes are insulated. 
     In the alternative or additionally thereto, in the foregoing embodiment, adjacent boxes of the plurality of boxes are detachably engaged to one-another. 
     In the alternative or additionally thereto, in the foregoing embodiment, each one of the plurality of boxes define a cavity and each cavity of the adjacent boxes are in fluid communication with one-another. 
     In the alternative or additionally thereto, in the foregoing embodiment, the transport containment assembly includes a supply duct in fluid communication between the refrigeration unit and a leading box of the plurality of boxes. 
     In the alternative or additionally thereto, in the foregoing embodiment, the supply duct is detachably connected to the leading box. 
     In the alternative or additionally thereto, in the foregoing embodiment, the transport containment assembly includes a return duct in fluid communication between the refrigeration unit and a trailing box of the plurality of boxes. 
     In the alternative or additionally thereto, in the foregoing embodiment, the return duct is detachably connected to the trailing box. 
     In the alternative or additionally thereto, in the foregoing embodiment, the transport containment assembly includes a supply duct in fluid communication between the refrigeration unit and a leading box of the plurality of boxes, and wherein the supply duct is detachably connected to the leading box; and a return duct in fluid communication between the refrigeration unit and a trailing box of the plurality of boxes, and wherein the return duct is detachably connected to the trailing box. 
     In the alternative or additionally thereto, in the foregoing embodiment, at least a portion of the plurality of boxes include a temperature sensor for measuring temperature of the cooling air. 
     In the alternative or additionally thereto, in the foregoing embodiment, each one of the plurality of boxes include a contoured top surface and a contoured bottom surface for stacking and guiding the plurality of boxes on top of one-another. 
     In the alternative or additionally thereto, in the foregoing embodiment, one of the top and bottom surfaces includes at least one groove and the other of the top and bottom surfaces includes at least one rail for receipt in the groove. 
     In the alternative or additionally thereto, in the foregoing embodiment, the grooves and the rails extend longitudinally in the direction of box engagement. 
     In the alternative or additionally thereto, in the foregoing embodiment, each one of the plurality of boxes include an inlet port and an outlet port for the flow of cooling air. 
     In the alternative or additionally thereto, in the foregoing embodiment, the transport containment assembly includes a first isolation device constructed and arranged to close the inlet port; and a second isolation device constructed and arranged to close the outlet port. 
     In the alternative or additionally thereto, in the foregoing embodiment, the first isolation device includes a pivoting damper and a resilient member, wherein the pivoting damper is biased in a closed position by the resilient member. 
     In the alternative or additionally thereto, in the foregoing embodiment, the flow of cooling air produces a differential pressure across the pivoting damper sufficient to open the first isolation device. 
     In the alternative or additionally thereto, in the foregoing embodiment, the second isolation device includes a shutter constructed and arranged to slide over the outlet port. 
     In the alternative or additionally thereto, in the foregoing embodiment, the transport containment assembly includes an alignment feature carried between adjacent first and second boxes of the plurality of boxes for aligning the outlet port of the first box with the inlet port of the second box. 
     A modular box for a transport containment assembly including a refrigeration unit, according to another, non-limiting, embodiment includes a plurality of walls defining a cavity for transport of cargo, wherein inlet and outlet ports are defined by and communicate through at least one of the plurality of walls for the flow of cooling air; a first isolation device constructed and arranged to close the inlet port and supported by at least one of the plurality of walls; and a second isolation device constructed and arranged to close the outlet port and supported by at least one of the plurality of walls. 
     The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. However, it should be understood that the following description and drawings are intended to be exemplary in nature and non-limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiments. The drawings that accompany the detailed description can be briefly described as follows: 
         FIG. 1  is a side view of a tractor trailer system as one, non-limiting, application of a transport containment assembly of the present disclosure; 
         FIG. 2  is a schematic of the transport containment assembly as one, non-limiting, exemplary embodiment of the present disclosure; 
         FIG. 3  is a perspective view of a modular box of the transport containment assembly; 
         FIG. 4  is a cross section of the modular box viewing in the direction of line  4 - 4  in  FIG. 3 ; and 
         FIG. 5  is a partial cross section of two adjacent modular boxes illustrating inlet and outlet ports with associated isolation devices. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , one, non-limiting, application for a transport containment assembly of the present disclosure is illustrated as a tractor trailer system  20 . The tractor trailer system  20  may include a tractor  22 , a trailer  24  and the transport containment assembly  26  that may be refrigerated. The tractor  22  may include an operator&#39;s compartment or cab  28  and an engine (not shown) which is part of the powertrain or drive system of the tractor  22 . The trailer  24  may include a plurality of wheels  30  rotationally engaged to a frame or platform  32  that may be detachably coupled to the tractor  22 . The frame  32  is constructed to support the containment assembly  26  for ground transport to desired destinations. The containment assembly  26  may be an integral part of the frame  32  or may be constructed for removal from the frame. 
     The transport containment assembly  26  may include a container  34  and a refrigeration unit  36 . The container  34  may include top, bottom, two sides, front and rear walls  38 ,  40 ,  42 ,  44 ,  46 ,  48  (also see  FIG. 2 ) that together define the boundaries of a cargo compartment  50 . The refrigeration unit  36  may be an integral part of the container  34  and located at or near the front wall  46 , and is constructed to cool cargo located in the cargo compartment  50 . The container  34  may further include doors (not shown) at the rear wall  48 , or any other wall. It is contemplated and understood that the transport containment assembly  26  may be constructed for other types of transportation other than tractor trailer systems and/or may be adapted for use in multiple types of transportation (e.g., ground, sea, and/or air). It is further understood that the container  34  may be any shape and may not be completely enclosed (e.g., no top wall  38  and/or no side walls  42 ,  44 , etc.). 
     Referring to  FIG. 2 , the transport containment assembly  26  further includes a plurality of boxes  52  that may be modular, a refrigerated air supply duct  54  and an air return duct  56 . The refrigeration unit  36  may include a compressor  58 , a condenser  60 , an expansion valve  62 , an evaporator  64 , and an evaporator fan or blower  66 . The compressor  58  may be powered by an electrical generator driven by an engine system (not shown). The fan  66  drives cooling air (see arrows  68 ) through the evaporator  64 , through the supply duct  54  and into the boxes  52 . From the boxes  52 , the cooling air returns to the refrigeration unit  36  via the return duct  56 . 
     The boxes  52  may be aligned in series with one-another such that cooling air  68  flows from a leading box  70  and to the next adjacent box. The cooling air  68  flows from one cooling box to the next adjacent cooling box, and until the cooling air flows through a trailing box  72 . Upon exiting the trailing box  72 , the cooling air  68  flows through the return duct  56  and back to the refrigeration unit  36 . The supply duct  54  and the return duct  56  may be flexible and are detachably engaged to the respective leading and trailing boxes  70 ,  72 , and each box  52  is detachably engaged, and in fluid communication with, the next adjacent box for the flow of cooling air  68 . The boxes  52  are generally stacked and sorted for easy removal of one box from the remaining boxes once the box has reached its delivery destination. The plurality of boxes  52  may be stacked in a multitude of rows. The shape and size of the boxes  52  may vary along with the height of each row and may be dependent, at least in-part, on the shape and/or various contours of the compartment  50 . 
     Referring to  FIGS. 3 through 5 , each box  52  may be thermally insulated and may include opposite side walls  74 ,  76 , opposite end walls  78 ,  80 , a bottom wall  82 , and a top wall  84 . The walls  74 ,  76 ,  78 ,  80 ,  82 ,  84  together define the boundaries of a thermally insulated cavity  86  for the storage and transport of cargo  88  that may require refrigeration. The end walls  78 ,  80  may each include at least one inlet port  90  with an associated first isolation device  92  and at least one outlet port  94  with an associated second isolation device  96 . The first and second isolation devices  92 ,  96  are configured to close when the associated boxes  52  are removed from the transport container  34  (or are otherwise not associated with an adjacent box). With the box  52  removed from the container  34  and no longer in fluid communication with the remaining boxes, closure of the isolation devices  92 ,  96  in the thermally insulated box  52  preserves the cold environment of the cavity  86 . 
     Referring to  FIG. 5 , an alignment feature  98  is generally carried between adjacent boxes  52  and may be associated with, or proximate to, the respective inlet and outlet ports  90 ,  94 . In one example, the alignment feature  98  may include a collar  100  that projects outward from a leading end wall  80  of a trailing box  52 , and a counter bore  102  in a trailing end wall  78  of the adjacent leading box. The collar  100  may define the boundaries of the inlet port  90  in the leading end wall  80 , and the counter bore  102  (in the trailing end wall  78  of the adjacent leading box) may be concentric to and in fluid communication with the outlet port  94  in the same trailing end wall  78 . When the leading box  52  is adjacent to the trailing box, the collar  100 , projecting outward from the leading end wall  80  of the trailing box, may fit snugly into the counter bore  102  in the trailing end wall  78  of the leading box. 
     As one, non-limiting, example, the isolation device  92  may include a damper  104  pivotally connected to the collar  100  and configured to be pivotally biased in a closed position (i.e. closes-off the inlet port  90 ). The damper  104  may be biased toward the closed position by a resilient member  106  that may be a spring. A force created by a differential pressure across the inlet port  90  (i.e., induced by the cooling air  68  flow) may be sufficient to overcome the biasing force of the resilient member  106  and thereby open the isolation device  92 . As one, non-limiting, example, the isolation device  90  for the outlet port  94  may include a shutter  108  that is manually slid over the outlet port  94  when the associated box  52  is removed from the container  34 . 
     It is further contemplated and understood that each end wall  78 ,  80  of each box  52  may include both inlet and outlet ports  90 ,  94  for versatility of positioning the boxes  52  within the container  34 . Moreover, the bottom and top walls  82 ,  84  may have similar inlet and outlet ports for the flow of cooling air  68  between rows of boxes  52  (see  FIG. 2 ) and detachable engagement of the supply and/or return ducts  54 ,  56 . It is further contemplated and understood that the isolation devices  92 ,  96  may be mechanically actuated by the act of coupling one box  52  to the next adjacent box (i.e., act of indexing one box  52  to the next adjacent box). In this example, the isolation devices  92 ,  96  may be identical and the inlet and outlet ports  90 ,  94  may be the same (i.e., direction of airflow through ports  90 ,  94  is dependent upon the positioning of the box  52 ). 
     Referring to  FIGS. 3 and 4 , the boxes  52  may be stacked directly adjacent to one another with the top wall  84  of a lower box in contact with a bottom wall  82  of an upper box. An indexing feature  110  may be carried between the upper and lower boxes  52  that aligns the boxes axially with respect to centerlines  112  of the coupling inlet and outlet ports  90 ,  94 . The indexing feature  110  may further guide the coupling of leading and trailing boxes. The indexing feature  110  may include at least one rail  114  (i.e. two illustrated) and at least one groove  116  for sliding receipt of the rail  114 . The rail  114  (i.e., two illustrated) may be defined by the contours of an external, bottom, surface  118  carried by the top bottom wall  82 . The groove  116  may have boundaries defined by the contours of an external, top, surface  120  carried by the top wall  84 . It is further contemplated and understood the location of the rails  114  and grooves  116  may be interchanged. 
     Referring to  FIG. 2 , each modular box  52  may include a temperature sensor  122  that outputs a temperature signal  124  to an electronic, central, device  126  that may monitor and record temperatures within each box and/or may utilize the temperature signal  124  to, at least in-part, control the refrigeration unit  36 . It is further contemplated and understood that not all boxes may require temperature sensors  122 . Moreover and for the purpose of controlling the refrigeration unit  36 , the temperature sensor(s) may be located in the supply and/or return ducts  54 ,  56  (not shown). 
     While the present disclosure is described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the present disclosure. In addition, various modifications may be applied to adapt the teachings of the present disclosure to particular situations, applications, and/or materials, without departing from the essential scope thereof. The present disclosure is thus not limited to the particular examples disclosed herein, but includes all embodiments falling within the scope of the appended claims.