Abstract:
A refrigerated case top duct member ( 122 ). The top duct member is the unitarily molded combination of a main panel ( 132 ) and a number of turning vanes ( 150, 152 ) at a forward end of the main panel. The member may be formed by vacuum molding.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to refrigerator cases. More particularly, the invention relates to structural integration of insulated panels in walls of such cases. 
         [0002]    Refrigerator cases (generically including freezers) are used in a variety of commercial situations. One key use is for retail display and vending. Many such cases include a closed rear wall and either an open front or a glass door front. 
         [0003]    Providing a forced air flow through the compartment of such cases is important for a number of reasons. Maintaining the desired food temperature in view of exposure to room air is an important factor. Moisture transport is another (e.g., to control undesirable condensation). One common forced flow scheme involves a cold air curtain downwardly discharged from a front top area of the compartment. a return flow is drawn through an intake at the bottom front of the compartment. 
         [0004]    The return flow may be drawn across a cooling heat exchanger (e.g., an evaporator) in a base of the case. The cooled air passes upward through a rear duct at the back of the compartment. The cooled air then passes forward through a top duct, at the front of the top duct, the air is turned downward by turning vanes to form the air curtain. The rear and top ducts may respectively be defined between rear and top insulated panels and non-insulated rear and top duct panels along the rear and top of the compartment. 
         [0005]    In addition to basic efficiency concerns, insulation may be appropriate to avoid or control condensation on components external to the compartment. This may be motivated by sanitary considerations in addition to refrigerator case longevity. 
         [0006]    A variety of top duct and vane assemblies are known. Exemplary assembly configurations are shown in U.S. Pat. Nos. 5,357,767, 5,475,987, 5,517,826, and 6,722,149. 
       SUMMARY OF THE INVENTION 
       [0007]    Accordingly, one aspect of the invention involves a refrigerated case top duct member. The top duct member is the unitarily molded combination of a main panel and a number of turning vanes at a forward end of the main panel. The member may be formed by vacuum molding. 
         [0008]    The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a view of a refrigerator case. 
           [0010]      FIG. 2  is a partially schematic side sectional view of the case of  FIG. 1 . 
           [0011]      FIG. 3  is a transverse horizontal sectional view of the case of  FIG. 2 . 
           [0012]      FIG. 4  is a view of a top duct panel of the case of  FIG. 1 . 
           [0013]      FIG. 5  is a longitudinal sectional view of the panel of  FIG. 4 , taken along  5 - 5 . 
       
    
    
       [0014]    Like reference numbers and designations in the various drawings indicate like elements. 
       DETAILED DESCRIPTION 
       [0015]      FIG. 1  shows a refrigerator case  20  having a front  22 , a back  24 , and left and right ends  26  and  28 . For purposes of reference, front, back, left, and right, are taken from the point of view of the case itself rather than a user facing the case. The case includes a base structure  30 , a rear wall structure  32 , and a top structure  34 . The case has a cooled interior volume or compartment  36 . The exemplary case has a series of vertical groups of shelves  38 . The exemplary case is a closed case having a sliding or hinged glass door front structure  40  and patch end or partition structures  42  and  44 . Partitions are used where cases are arrayed side-by-side; patch ends are used at the two ends of the array. Alternative cases are open-front. 
         [0016]    The exemplary base  30  includes front and back transverse rails  50  and  52  for supporting the remainder of the base and, therethrough, the remainder of the case atop a ground/floor surface. The exemplary base  30  contains the refrigeration equipment (e.g., an evaporator, and the like shown schematically as  60  in  FIG. 2 ). The evaporator may be connected to a central compressor and condenser elsewhere in the facility. Alternatively, the case equipment could be self-contained.  FIG. 2  further schematically shows an air flowpath having a first portion  510  carrying cooled air from the equipment  60  to a rear air flowpath section or duct  62 . A second portion  512  flows upward through the rear duct  62 . A third portion  514  flows forward from the top of rear duct  62  through a top duct  64 . A fourth portion  516  exits the top duct near the forward end of the top  34  and is discharged downward along the front  22 . A return portion  518  is drawn back into the equipment  60  through a grate  66  near the forward top portion of the base  30  immediately in front of a base cover member  68 . 
         [0017]      FIG. 3  shows further details of the rear duct  62 . The duct  62  is segmented by a series of interior uprights including a left upright  70 , a right upright  72 , and a series of intermediate uprights  74 . Forwardly, the duct segments are each bounded by an associated duct panel  80  (e.g., mounted by fasteners  81  to side portions of forward flanges  82  of the adjacent two uprights). As is discussed in further detail below, each shelf  38  may be mounted to these uprights (e.g., a single width shelf spanning and mounted to exactly two adjacent such uprights via mounting apertures in root portions of the flanges  82 ). Rearwardly, the duct segments are collectively bounded by the forward surfaces of panels of an insulated panel assembly  84 .  FIG. 2  shows the panel assembly  84  as including an upper panel  86  and a lower panel  88 . 
         [0018]      FIGS. 2 and 3  further show the base  30  as including a series of support brackets or braces  90  extending front-to-back spanning the rails  50  and  52 . Mounted to and extending upward from a rear end portion of each brace  90  is a rear external support  92 . Each support  92  has a lower end  94  mounted to the rear end portion  96  of the associated brace  90  and has an upper end  98 . As is discussed in further detail below, the panel assembly  84  is sandwiched between the uprights  70 ,  72 , and  74  along the front and the supports  92  along the rear. 
         [0019]    The top duct  64  may be similarly segmented or may be substantially unsegmented.  FIG. 2  shows the top duct  64  defined between a top insulated panel  120  and a side-by-side array of interior top duct panels  122 . Each of the panels  122  is unitarily molded as a single piece of a polymeric material (e.g., ABS or polystyrene). The exemplary panels  122  are generally rectangular in planform extending from a rear end  124  to a front end  126  and between left and right edges  128  and  130 . The panel  122  has a main body portion  132  also generally rectangular in planform. A short rear wall  134  depends from a rear edge of the main body  132  to engage and seal with the associated rear duct panel  80 . At a front edge of the main body  132  a shorter wall  136  depends. Edge flanges  138  and  140  extend upward along edges of the panel including along the main body  132 . First and second turning vanes  150  and  152  extend between the flanges  138  and  140  and are supported thereby. Each exemplary vane  150 ;  152  extends from a leading edge  154 ;  156  to a trailing edge  158 ;  160 . A leading portion  162 ;  164  of each vane extends from the leading edge generally parallel to the main body  132 . These portions split the flow  514  into an exemplary two portions  515 A and  515 B to, in turn, merge at an outlet  170  formed at the trailing side downstream edges  158  and  160  to form the flow  516 . To turn the flow, the exemplary vanes each have an intermediate portion  172 ;  174  transverse to the leading portion  162 ;  164  (e.g., perpendicular thereto in the exemplary embodiment). A downstream end portion  176 ;  178  extends from the associated intermediate portion to the associated downstream/trailing edge  158 ;  160 . In the exemplary embodiment, these portions are oriented to provide a total flow turn of approximately 120°, more broadly about 80-120°. The panel  122  has an exemplary width W of 0.5-1.5 m and an exemplary depth D of 0.5-1.5 m. An exemplary thickness of the main body portion  132  is 1-5 mm. 
         [0020]    In various implementations, the top duct panel  122  may be formed as a drop-in replacement for an existing panel assembly. The panel  132  may thus duplicate the overall dimensions and flow exit angle(s) of the existing panel. Exemplary discharge angles are 70-140° and may be other than a single angle (e.g., a fanned group of vanes). 
         [0021]    One or more embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, the foregoing teachings may be applied in the reengineering of an existing case configuration. In such a reengineering, details of the existing configuration will influence or dictate details of any particular implementation. Accordingly, other embodiments are within the scope of the following claims.