Patent Publication Number: US-8528288-B1

Title: Insulated panel arrangement

Description:
This application is a continuation-in-part of U.S. patent application Ser. No. 13/086,125, filed Apr. 13, 2011. 
    
    
     BACKGROUND 
     The present invention relates to an insulated panel arrangement for insulated panels such as those used in walk-in coolers. 
     Walk-in coolers and environmental test chambers are typically constructed of individual, insulated panels which are then latched together with hooks on one panel which engage pins on a second panel. The hooks are mounted on a cam arrangement so they can be rotated to pull the panels tightly together. The panels typically are fabricated from an expanded polyurethane foam insulation which is blown in between walls of relatively thin metal skins (typically 22 gauge steel or stainless steel). The panel ends are designed to match up in a tongue and groove configuration with the ends of the metal skins abutting each other. 
     The latch mechanisms are encased in the foam insulation. If the latch mechanisms shift relative to their respective panels, the fit between the panels may become loose, which is undesirable, as it allows air to leak through the gaps that are created between the panels and may affect the structural strength of the enclosure. 
     Prior art attempts to prevent shifting of the latch mechanisms relative to their respective panels have included the addition of “wings”, as shown in U.S. Pat. No. 6,299,224 “Finkelstein”, which is hereby incorporated herein by reference. The “wings” provide a large bearing surface for the latch mechanism to bear against the foam insulation to try to reduce the amount of shifting of the latch. However, in some instances, particularly when the foam insulation is subjected to very high temperatures or when it is exposed to high relative humidity, the foam insulation begins to break down, and the latches still become loose. 
     In very high temperature applications, such as in oven chambers, mineral wool insulation is used in the core space instead of foam insulation. Mineral wool insulation is not capable of bearing any weight, so it cannot be used as a structural member. Since the temperature differential in these panels is even greater than in the foam insulated panels, it is especially desirable to keep the heat transfer between the inner skin of the panel (inside the oven chamber) and the outer skin of the panel to a minimum. 
     SUMMARY 
     An embodiment of the present invention provides a means for transferring the latching forces to the metal skins of each panel. The forces are transferred in such a manner that, when two panels are tightened snugly together, the forces are applied to the metal skins directly opposite to each other. This provides greater latching strength and prevents deformation of the metal skins and shifting of the latches relative to the panels, so the panels remain snugly against each other, even if the insulation begins to break down due to heat and humidity or other factors. In at least one embodiment, there are two spaced-apart hooks on each latching mechanism, which adds even greater strength. The latching arrangements shown here are particularly useful for panels that are used outdoors, where there may be high wind load conditions such as hurricanes, and for high temperature conditions, high humidity conditions, and a combination of all these negative conditions. Also, by holding a tight seal even under high temperature conditions, this latching arrangement provides greater fire resistance than prior art latching arrangements. 
     In one embodiment, where mineral wool insulation is used instead of foam insulation, discrete spacers provide structural support to the skins of the panel while minimizing the contact area between inner and outer skins so as to reduce heat transfer. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of two insulated panels made in accordance with the present invention, with the panels partially broken away to show two of the latch mechanisms; 
         FIG. 2  is a view along line  2 - 2  of  FIG. 1 ; 
         FIG. 3  is a view along line  3 - 3  of  FIG. 1 ; 
         FIG. 4  is a view along line  4 - 4  of  FIG. 6 ; 
         FIG. 5  is a view showing a prior art latching arrangement just before it is latched; 
         FIG. 6  is a view taken along line  6 - 6  of  FIG. 1 ; 
         FIG. 7  is a view similar to  FIG. 6 , but with the insulated panels still apart from each other, before they have been latched together; 
         FIG. 8  is a view similar to  FIG. 6 , but with the hooks engaging the pin, before the panels are snugged up tightly together; 
         FIG. 9  is a side view of the rod support member of  FIGS. 6-8 ; 
         FIG. 10  is a side view, similar to  FIG. 7 , but for another embodiment of a latching arrangement; 
         FIG. 11  is a side view, similar to  FIG. 10 , but for another embodiment of a latching arrangement; 
         FIG. 12  is a side view, similar to  FIG. 8 , but for another embodiment of an insulated panel made in accordance with the present invention; 
         FIG. 13  is a side view, similar to  FIG. 7 , but for another embodiment of a latching arrangement; 
         FIG. 14  is a side view, similar to  FIG. 7 , but for another embodiment of a latching arrangement involving a wall panel and a ceiling panel; 
         FIG. 15  is a side view of the rod support member of  FIGS. 6-8 ; 
         FIG. 16  is a view similar to that of  FIG. 6 , but for a prior art latching arrangement for use in very high temperature panels; 
         FIG. 17  is a view similar to that of  FIG. 16 , showing the prior art panels before they are snugged up together, but with the mineral wool insulation omitted for clarity; 
         FIG. 18  is a side view of an insulated panel made in accordance with the present invention, with the panel partially broken away to show one of the latch mechanisms; 
         FIG. 19  is a view along line  19 - 19  of  FIG. 18 ; 
         FIG. 20  is a view along line  20 - 20  of  FIG. 19 , but showing also a mating panel, similar to the view of the latching arrangement of  FIG. 11 ; and 
         FIG. 21  is a view along line  21 - 21  of  FIG. 18 . 
     
    
    
     DESCRIPTION 
       FIGS. 1 and 2  show two rectangular insulated panels  10  fitted snugly together to form a wall. Each panel  10  is made up of an inner planar skin  14  and a parallel outer planar skin  16 . A urethane expanded foam insulation core  12  fills the interior space between the inner and outer skins  14 ,  16 . In this particular embodiment, the core  12  is five inches thick and the inner and outer skins  14 ,  16  are 22 gauge steel sheets. 
     Each of the planar skins  14 ,  16  has a top edge  11  at the top end of the panel  10  and an opposed bottom edge  13  at the bottom end of the panel  10 . Each of the planar skins  14 ,  16  also has a left edge  15  at the left end of the panel  10  and an opposed right edge  17  at the right end of the panel. Latching arrangements  18  hold the panels together. As shown in  FIG. 4 , a hook assembly  20 , mounted on one panel  10 , mates with a pin assembly  22  mounted on a second, adjacent panel  10  such that, as the hook assembly  20  is rotated in the direction of the arrow  24 , the hook  26  on the hook assembly  20  engages the pin  28  on the pin assembly  22 . Further rotation of a hex head wrench (not shown) on the rod  29  of the hook assembly  20  rotates the hook  26  and results in a cam action wherein the hook  26  retracts into its panel  10 , pulling the pin  28  of the pin assembly  22  toward the hook assembly  20  to draw the insulated panels  10  together for a snug fit, as described in more detail later. The hook  26  is mounted on the rod  29  and rotates with the rod  29  and about the axis of the rod  29 . The cam-action hook assembly  20  for this embodiment is part number 1168, supplied by Kason Industries of Woodmere, N.Y.. 
     As shown in  FIGS. 1-3 , in this particular embodiment, the hook assemblies  20  are mounted on the left end and top end of each panel  10 . The corresponding pin assemblies  22  are mounted on the right end and bottom end of each panel directly opposite their respective hook assemblies  20 . For example, the hook assemblies  20  on the left end are at the same elevations as the respective pin assemblies  22  on the right end, which puts each hook assembly  20  directly opposite a pin assembly  22  so that, when the left end of one panel abuts the right end of another panel, the hook assemblies  20  on the left end of the one panel are properly aligned with the respective pin assemblies  22  of the other panel. Similarly, the hook assemblies  20  on the top end are directly opposite the pin assemblies  22  on the bottom end so that, when one panel  10  is placed below another with their left and right ends aligned, the hook assemblies  20  on the top end of the bottom panel are properly aligned with the pin assemblies  22  on the bottom end of the upper panel. 
     In this particular embodiment, each panel  10  has three hook assemblies  20  on its left end, three pin assemblies  22  on its right end, two hook assemblies  20  on its top end, and two pin assemblies  22  on its bottom end. This arrangement allows the hooks  26  on the left end of one panel  10  to engage the corresponding pins  28  on the right end of the next adjacent panel  10  to the left. It also allows the hooks  26  on the top end of one panel  10  to engage the corresponding pins  28  on the bottom end of the next adjacent panel  10  above (not shown). 
     The insulated panels  10  have a tongue  38  and groove  40  configuration along the panel ends so they can match up to each other. As shown best in  FIG. 7 , the left and right opposed edges  15 ,  17  of the inner and outer skins  14 ,  16  are bent toward the other of the skins  16 ,  14 , respectively, to form left and right opposed end faces  42 ,  44 . In this particular embodiment, the end faces  42 ,  44  are perpendicular to the planar skins  14 ,  16 , and the edges are also bent back parallel to the planar skins  14 ,  16  to form return legs  43 . The left and right end faces  42 ,  44  and return legs  43  run the full length of their respective edge  15 ,  17 . This same arrangement occurs at the top and bottom edges  11 ,  13 . 
     Gaskets  46  are placed on the outer surface of one or both of the end faces  42  to provide a tighter seal between the insulated panels  10 . 
     It should be pointed out that, in the prior art arrangement shown in  FIG. 5 , the hook assembly  20 P and the pin assembly  22 P are both encased in and anchored to the foam insulation  12 . Wings  32  on the hook assembly  20 P and similar wings  34  and  36  on the pin assembly  22 P help anchor their respective assemblies  20 P,  22 P to the foam insulation  12 . 
       FIGS. 6-8  show the latching arrangement  18  in more detail. In this particular embodiment, there are two hook assemblies  20  engaging a single pin assembly  22 . However, as shown in  FIG. 13  and explained in more detail later, the number of hook assemblies  20  may vary from a single hook assembly  20  to three or more hook assemblies  20 . The number of pin assemblies  22  also may vary, as shown for a different embodiment in  FIG. 10 . 
     Referring now to  FIG. 6 , the latching arrangement  18  includes two hook assemblies  20 , each of which is substantially identical to the hook assembly  20 P of  FIG. 5 . A hexagonal cross-section rod  29  extends between the hook assemblies  20  and connects them together. The pin assembly  22  uses a single pin  28  extending substantially the full thickness of the insulated panel  10 . The latching arrangement  18  also includes two rod support members  54 , two pin support members  55 , and a spacer  56 , as described in more detail below. 
       FIG. 15  is a side view of one of the pin support members  55  of  FIGS. 6-8 . (This pin support member  55  is identical to the rod support member  54  of  FIG. 9 , except for the location of the holes  76 ,  74  respectively, as described in more detail later) The pin support member  55  has a generally T-shaped cross-section, with three legs  60 ,  62 ,  64 . The first leg  62  and second leg  64  have planar skin abutment surfaces  62 A,  64 A, respectively, which, when installed, lie flat along the interior surface of their respective planar skin  14 ,  16 . The first leg  62  has an end surface  66 , which is at right angles to the planar skin abutment surface  62 A. As shown in  FIG. 7 , this end surface  66  abuts and bears against the interior surface of one of the end faces  44  of the skin of the insulated panel  10 . (Similarly, the end surface  66  of the rod support member  54  abuts and bears against the interior surface of one of the end faces  42  of the skin of the insulated panel  10 .) A concave recessed surface  68  is located opposite the leg  60 . Small V-notches  70 ,  72  on the leg  60  and on the concave recessed surface  68 , respectively, mark the spot for drilling holes into or through the leg  60 , as required, to receive the pin  28  or the hex rod  29 , as described later. 
     The pin support member  55  (and the rod support member  54 ) may be made in any of a number of known ways, such as an extrusion, preferably made of extruded aluminum, or a casting, preferably made of metal, or even a bent steel piece. The length of the support members  54 ,  55  (extending in a direction perpendicular to the page in  FIGS. 9 and 15  and in the vertical direction in  FIG. 4 ) may vary depending on the application, but the length typically ranges from 6 inches to 18 inches. As may be appreciated from  FIG. 6 , the support member  54 ,  55  is a universal piece which is flipped about its axis for use on opposite walls  14 ,  16  and on opposite sides of the insulated panel  10 . 
       FIG. 15  shows in dotted lines a drilled hole  74  aligned with the V-notch  70  for receiving the pin  28 .  FIG. 9  shows in dotted lines a drilled hole  76  aligned with the V-notch  72  for receiving the rod  29 . These holes  74 ,  76  may be drilled depending on the application, such that only the support members  55  to be used to receive the pin  28  are drilled with the hole  74 , and only the support members  54  to be used to receive the hex rod  29  are drilled with the hole  76 . The hole  76  in the rod support member  54  is drilled completely through the rod support member  54  on at least one side of the panel  10 , so a hex wrench can access the rod  29  to rotate the rod  26  and the hooks  26  that are mounted on the rod  29 . 
     To assemble the latching arrangement  18 , the ends of a pin  28  are inserted into the holes  74  of two opposite pin support members  55 , and this pin assembly  22  is pushed into the mold (prior to blowing in the foam insulation  12 ) such that the end surfaces  66  of the support members  55  are abutting the interior surfaces of their respective end faces  44  of their inner and outer skins  14 ,  16 . Likewise, two hook assemblies  20  are mounted on a common hex rod  29  which extends through the openings  76  of two rod support members  54 , with a spacer  56  extending between the two adjacent hook assemblies  20 , and this complete assembly  80  is pushed into the mold (prior to blowing in the foam insulation  12 ) such that the end surfaces  66  of the rod support members  54  abut the interior surfaces of the end faces  42  of the inner and outer skins  14 ,  16 . The hex rod  29  projects into the cavity formed by the concave recess  68  to allow a user to use a socket head wrench to rotate the rod  29 , which rotates both of the hook assemblies  20  to engage with or disengage from the pin  28  of the adjacent panel  10 . The spacer  56  is a hollow cylinder mounted concentrically with and surrounding the hex rod  29 . 
     The pin  28  has an inner end portion adjacent to the inner skin  14 , an outer end portion adjacent the outer skin  16 , with the pin  28  lying between and extending perpendicular to the inner and outer planar skins  14 ,  16 . The inner pin support member  55  has surfaces  62 A,  64 A that abut the interior surface of the inner skin  14 , and the outer pin support member  55  has surfaces  62 A,  64 A that abut the interior surface of the outer skin  16 . 
     The rod  29  has an inner end portion adjacent to the inner skin  14  and an outer end portion adjacent to the outer skin  16 , with the rod  29  lying between and extending perpendicular to the inner and outer planar skins  14 ,  16 . The inner rod support member  54  has surfaces  62 A,  64 A that abut the interior surface of the inner skin  14 , and the outer rod support member  54  has surfaces  62 A,  64 A that abut the interior surface of the outer skin  16 . 
     An insulated panel  10  will typically have hook assemblies  20  along two adjacent ends of the insulated panel  10  (typically in the tongue portions of the tongue and groove profiles of the insulated panel  10 ), and pin assemblies  22  along the other two ends of the insulated panel  10  (typically in the groove portions of the tongue and groove profiles of the insulated panel  10 ), as shown in  FIGS. 1-3 . Once the hook assemblies  20  and the pin assemblies  22  have been installed into a mold in the desired locations along the ends of the insulated panel  10 , the foam insulation  12  may be blown in to fill the space between the walls  14 ,  16 , including the area surrounding the hook assemblies  20  and the pin assemblies  22 . If no measure has been taken to prevent the foam insulation  12  from covering up the portions of the pin  28  which engage the hooks  26  of the hook assemblies  20 , it may be necessary to cut out and remove small channels (not shown) of the foam insulation  12  to provide such access. 
     The assembly of adjacent insulated panels  10  is shown in  FIGS. 6-8 . First, the insulated panels  10  are brought together such that the tongue portion  38  of one insulated panel  10  is lined up with the groove portion  40  of the adjacent insulated panel  10 , as shown in  FIG. 7 . In this configuration, the hook assemblies of the first panel  10  line up with the pin assembly  22  of the adjacent panel  10 . 
     The installer then brings the two panels closer together, as shown in  FIG. 8 , and uses a socket head wrench (not shown) to engage one end of the hex rod  29  and rotates the hex rod  29  which also rotates the hooks  26  of the hook assemblies  20  to a first position wherein the hooks  26  engage the pin  28  of the pin assembly  22 . Further rotation of the hex rod  29  results in a cam action which retracts the hooks  26  back into their respective panel  10 , as shown in  FIG. 6 . This brings the adjacent ends of the two adjacent panels  10  snugly together. 
     As shown in  FIG. 6 , this final tightening action results in the following load forces:
         a) The force Fp resulting from the hooks  26  of the hook assemblies  20  pulling on the pin  28 . This force Fp is transmitted to the pin support members  55  by the pin  28 , and is in turn transmitted to the end faces  44  (See  FIG. 8 ) of the inner and outer skins  14 ,  16  of one of the insulated panels  10  as forces Fp/2.   b) An equal magnitude, opposing force Fc on the rod  29  resulting from the resistance by the pin  28 . This force Fc is transmitted to the rod support members  54  by the hex rod  29 , and is in turn transmitted to the end faces  42  (see  FIG. 8 ) of the inner and outer skins  14 ,  16  of the other insulated panel  10  as forces Fc/2.       

     It should be pointed out that these pairs of opposing forces Fp/2, Fc/2 are substantially of the same magnitude but acting directly against each other, as shown also in  FIG. 4 . Furthermore, the full magnitude of these opposing forces Fp/2, Fc/2 only comes into play when the end faces  42 ,  44  of the adjacent panels  10  are abutting each other, as shown in  FIGS. 4 and 8 . Since the forces Fp/2, Fc/2 are of the same magnitude but act in opposite directions on their corresponding end faces  42 ,  44 , and since these corresponding end faces  42 ,  44  abut each other when the panels  10  are snugged up tightly against each other, these forces Fp/2, Fc/2 cancel each other out and do not act to deform the skins  14 ,  16 . Finally, even if the foam insulation  12  in the insulated panels  10  deteriorates or breaks down, this latching arrangement  18 , being substantially independent of the foam insulation  12 , does not shift relative to the panels  10 , so the panels  10  remain snugly engaged with each other. 
     It should be noted that it is not necessary for the full lengths of the end faces  66  of the opposing support members  54 ,  55  to be exactly coextensive with each other. However, it is desirable for at least a portion of one of the end faces  66  of one support member to lie directly opposite the end face  66  of the opposing support member and even more desirable for a large portion of the opposing end faces  66  to lie directly opposite each other in order to prevent deformation of the skins  14 ,  16 . 
       FIG. 10  shows a second embodiment of a latching arrangement  18 ′. Comparing  FIG. 10  with the embodiment of  FIG. 7 , it is readily apparent that the only substantial difference is the fact that this embodiment has two separate pins  28 ′ which extend only a short distance into the panel  10 ′ instead of a single, longer pin  28  which extends substantially the full width of the panel. In this embodiment, each pin assembly  22 ′ individually transfers the clamping load of the opposite hook assembly  20  to its corresponding support member  55 , which in turn transfers its load to its corresponding end face  44 . In this case, there will be a bit of a cantilevered load on the pin  28 ′, tending to cause the leg  64  of the pin support member  55  to want to rotate toward the interior about the leg  62 . However, the opposing force from the foam  12  prevents any rotation, and the main force is still transmitted to the end face  44  as in the previous embodiment. Other than this structural difference, the latching arrangement  18 ′ operates in substantially the same manner as the latching arrangement  18  described above. 
       FIG. 11  shows another embodiment of a latching arrangement  18 *. In this instance, the T-shaped support members  54 ,  55  have been replaced with rectangular support members  54 *,  55 * which serve substantially the same function, that is, to transfer the clamping loads to the end faces  42 *,  44 *. In this case, the end faces  42 *,  44 * are deeper such that the end surfaces  66 * of the support members  54 * fit against the end faces  42 * along with the ends of the hook assemblies  20 , so both the support members  54 * and the hook assemblies  20  apply force to the end faces  42 *. 
     While  FIG. 11  shows an embodiment in which there are two pins  28 *, similar to the arrangement of  FIG. 10 , it should be clear that a single pin arrangement, similar to that of  FIG. 6 , may be substituted for the two pins  28 *. The latching arrangement  18 * works in substantially the same manner as the latching arrangement  18  described earlier. 
       FIG. 12  shows another embodiment of an insulated panel  10 **. Comparing this insulated panel  10 ** with the insulated panel  10  of  FIG. 8 , it may be appreciated that the latching arrangement  18  remains unchanged. The main difference here is that substantially all of the interior surface of the outer skin  16  has been lined with a high temperature insulating barrier  82 ** to further protect the foam insulation  12  from temperature extremes. Various high temperature barrier materials could be used for the liner  82 **, such as Fiberfrax by Unifrax LLC from Niagara Falls, N.Y.. This insulating liner  82 ** may be placed on the interior surface of either or both of the skins  14 ,  16  of the insulated panel  10 **. 
     In this embodiment, a high temperature moisture barrier  84 ** has been applied to all the exposed ends of the foam insulation  12 . The high temperature moisture barrier  84 ** prevents moisture migration into the foam insulation  12  to protect the foam insulation  12 , even in high humidity and high temperature applications. The moisture barrier  84 ** may be a silicone coating, a moisture proof tape such as aluminum duct tape, a combination of a silicone coating and tape, or other moisture resistant materials. 
       FIG. 13  shows another embodiment of a latching arrangement  18 ″. A comparison with the embodiment of  FIG. 6  shows that this latching arrangement is substantially identical except for the use of a third hook assembly  20  and the use of two shorter spacers  56 ″ between adjacent hook assemblies  20 . Other than this structural difference, this embodiment operates in the same manner as the latching arrangement of  FIG. 6 . 
       FIG. 14  shows one more embodiment of a latching arrangement which may be used to connect a regular wall panel  10  to a ceiling panel  10 C (which may also be a floor panel). The hook arrangement  80  is identical to the hook arrangement  80  of  FIG. 8 . The pin assembly  22 C is similar to the pin assembly  22  of  FIG. 8 , except that the leftmost pin support member  55 L is an angle iron which serves the same purpose as the support member  55 , of transferring the force from the pin  28  to the skin  14 C but is better suited to the physical configuration of the ceiling or floor panel. Other than this structural difference, this embodiment operates in the same manner as the latching arrangement  18  of  FIG. 8 . 
       FIGS. 16 and 17  are section views showing two prior art panels  100  used in very high temperature applications, such as in walk-in oven chambers. These panels  100  are filled with mineral wool insulation  102  because the more conventional urethane foam insulation discussed earlier cannot withstand the high temperatures encountered in this type of application. However, since mineral wool insulation  102  is not weight-bearing, it cannot be relied upon for structural support. As is better appreciated in  FIG. 17 , the panels  100  include “C” channel members  108  extending substantially the full length (height) of the panel  100  along both the left and the right ends of the panel  100  between the inner skin  104  and the outer skin  106 . 
     During assembly, these panels  100  are brought together so that their corresponding “C” channel members  108  interlock with each other, as shown in  FIG. 16 . The space between these “C” channel members  108  is filled with mineral wool insulation  110  during this assembly process, and then the panels  100  are screwed together with self-tapping zip screws  112 , as shown in  FIG. 16 . This assembly process is time-consuming and tedious. It is next to impossible to check whether the installer forgot to place the mineral wool insulation  110  in the space between the “C” channel members  108  until after start-up, when the problem manifests itself in higher than expected temperatures on the cold side  106  at the connection of the panels  100 . The “C” channel members  108  also provide a large contact area which results in undesirable heat transfer from the hot side  104  to the cold side  106  of the panels  100 . 
     Referring to  FIGS. 18-21 , the high temperature panels  115  made in accordance with an embodiment of the present invention include inner and outer skins  104 ′,  106 ′. 
     Referring to  FIG. 20 , the left and right opposed edges  114 ,  116  of each of the inner and outer skins  104 ′,  106 ′ are bent toward the other of the skins  106 ′,  104 ′, respectively, to form left and right opposed end faces  118 ,  120 . (The top and bottom edges also are bent inwardly in the same manner.) Gaskets  122  are installed on at least one of these left and right opposed end faces  118 ,  120  to aid in sealing the panels  115  against each other. Mineral wool insulation is placed in the space  108  between the inner and outer skins  104 ′,  106 ′. 
     Rod support members  124  and pin support members  126 , similar to the rod support members  54 * and pin support members  55 * of  FIG. 11 , are placed inside the opposing faces  118 ,  120  respectively of the panels  115 . These support members  124 ,  126  are secured to the inside of the opposing faces  118 ,  120  by suitable means, such as by an adhesive or by welding. As shown in  FIG. 20 , each rod support member  124  is directly opposite a respective pin support member  126 , and each hook  130  is directly opposite an opening to the pin  136 . The rod  138  has a hexagonal shape, and, when it is rotated, it rotates both hooks  130 . 
       FIG. 21  shows a detail of the installation of the rod support members  124  when welding is chosen as a securing option. Through openings  128  are drilled or punched through the face  118  of the inner and outer skins  104 ′,  106 ′ at the desired height of the support members  124 . The support members  124  are then placed inside the face  118  and the support members  124  are tack welded to the face  118  through the openings  128 . It should be noted that the pin support members  126  are mounted in a similar manner to the inside of their respective face  120 . 
     As shown in  FIGS. 20 and 21 , each of the end faces  118  extends from its respective inner or outer planar skin  104 ′ or  106 ′ toward the other planar skin  106 ′ or  104 ′ and extends beyond one of the hook assemblies  130  and beyond the two rod support members  124  for that respective hook assembly  130 , terminating at a peripheral edge  107  or  109 . The peripheral edges  107 ,  109  are spaced apart from each other, with the spacers  132  maintaining a fixed spacing between the peripheral edges  107 ,  109 . The two rod support members  124  for each hook assembly  130  are located on the inner and outer sides of the respective hook assembly  130 , with both of the rod support members  124  for each hook assembly  130  bearing against the same end face  118  of the same planar skin  104 ′ or  106 ′. In addition to the through openings  128  that are used for tack welding the support members  124  to their respective skin  104 ′,  106 ′, each of the end faces  118  also defines a slotted through opening  131  aligned with its respective hook  26  to provide a space that permits the respective hook  26  to extend through the end face  118  of the respective planar skin  104 ′ or  106 ′ to reach the pin  28  of the next panel. 
     A pin support member  126  is located opposite each of the rod support members  124 , with two pin support members  126  for the pin  136  bearing against the second end face  120  of the inner planar skin  104 ′ and two pin support members  126  for the pin  136  bearing against the second end face  120  of the outer planar skin  106 ′. 
     As was mentioned earlier, the mineral wool insulation  108  is not weight-bearing, so it cannot be relied upon to maintain the inner and outer skins  104 ′,  106 ′ in spaced apart relationship to each other. On the end  114  of the panel  115 , which has the rod support members  124  (which rotationally support the hook assemblies  130  (See also FIG.  18 )), “C” shaped spacers  132  are placed at regular intervals along the length of the panel  115  to keep the inner and outer skins  104 ′,  106 ′ in a uniform, spaced apart relationship. These spacers  132  are very short relative to the overall length of the panel  115 . In one embodiment, the spacers  132  are tack welded at their four corners  134  (See also  FIG. 21 ) to the faces  118  of the inner and outer skins  104 ′,  106 ′. Since the spacers  132  contact such a small surface area of the skins  104 ′,  106 ′, this results in a very small surface area available for heat transfer from the hot, inner skin  104 ′ to the cold, outer skin  106 ′. 
     At the other end  116  of the panel  115 , the pin  136 , supported by the pin support members  126 , functions as a spacer to keep the inner and outer skins  104 ′,  106 ′ in spaced apart relationship. The ends of the pin  136  contact the inside of the inner and outer skins  104 ′,  106 ′ to keep these skins in a uniform, spaced apart relationship. 
     Note that the spacers  132  are used on the end  114  of the panel  115  which has the rod support members  124  because at least one end of the rod  138 , which is rotationally supported by the support members  124 , is exposed through an opening  140  (See  FIG. 20 ) to allow the user access to rotate the hook assemblies  130  during the assembly or disassembly process, as described earlier with respect to previous embodiments, and therefore cannot be used to hold the skins apart in the same manner as the pins  136 . 
     Referring to  FIG. 18 , it may be appreciated that two ends of the panel  115  (in this instance the top and right ends) include the hook assemblies  130 , and therefore use spacers  132  to maintain the inner and outer skins  104 ′,  106 ′ in spaced apart relationship. The other two ends (in this instance the bottom and the left ends) include the pins  136  and the pin support members  126 , with the pins  136  also serving as spacers to maintain the inner and outer skins  104 ′,  106 ′ in spaced apart relationship. Other than these structural differences, this embodiment operates in the same manner as the latching arrangement  18 * of  FIG. 11 . 
     The embodiments described above show several latching arrangements for use with insulated panels. It will be obvious to those skilled in the art that modifications may be made to the embodiments described above without departing from the scope of the invention as claimed.