Abstract:
A ruggedized case for transportation and protection of electronic equipment used in harsh commercial or military environments. The ruggedized case is 30-70% lighter than other similar competing cases through the use of lightweight, low-density, superior strength composite materials. The ruggedized case includes a multi-panel case body open at each end and two removable covers. A chassis which may be vibration and shock isolated, and a removable rack mount frame are also provided. Each component of this ruggedized case, including recessed cover latches, and handles, weather and airtight seals, adjustable rack mount frame lock mechanisms, and vibration isolators, have been significantly improved to provide more ergonomic form and functionality.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to container systems for commercial and military packaging which protect electronic equipment against damage caused by shipping and other rough handling, and more particularly to a ruggedized container system for housing and environmental isolation of sensitive electronic equipment utilizing lightweight superior strength composite structural materials and unique component designs for superior weight reduction, functionality, and longevity. 
     2. Description of Related Art 
     Electronic equipment of the type typically used in commercial or military environments has not been designed to withstand extreme military transport, high impact or shock environment. Therefore, a variety of reinforced and ruggedized container systems have been developed to protectively house and transport electronic equipment. One such system is disclosed in U.S. Pat. No. 5,808,866 invented by Porter bearing these design goals and attributes. 
     A company called ECS Case located in Grants Pass, Oreg., manufactures and distributes ECS composite rack mount cases which include removable shock mounted aluminum racks, scoveres and quick release fasteners, composite center bodies and composite removable covers. Although being commercially viable, ECS rack mount cases are lacking structural and component sophistication. 
     Hardigg Industries of South Deerfield, Mass. also manufactures and distributes a line of rotomolded plastic rack mount containers designed to protect house and transport sensitive electronic equipment mounted therein. While these HARDIGG containers meet all of the environmental requirements and federal test method standards, nonetheless the overall size, weight and bulkiness, lack of sophistication of manufacturing techniques, and various other component and accessory functionality leave much to be desired from this product line. 
     The commercial off-the-shelf transportation cases are typically not intended for use in the harsh military environment. The requirements of military transit cases are lightweight, crush proof, stackable, air and water tight, and securely transportable for harsh environments particularly environments characterized by high vibration/shock levels, rough shipping and handling and temperature extreme. The weight of the case used in military environment may be critical, for example, in a battlefield where the electronics package should be sufficiently light to be transported and placed in a selected position by at most two persons. In addition, it is very important to build into these containers a shock mitigation system which is capable of protecting sensitive electronic equipment from possible damages during harsh transport. 
     The present invention addresses all of the needs currently unmet by the so-called lightweight, superior strength ruggedized enclosures for protecting housings and transporting sensitive electronic equipment and modules subjected to a harsh environment of severe vibration and physical impact, corrosive atmosphere and temperature extremes. Several embodiments of both overall case structure and component features, along with manufacturing methodology are disclosed. The net effect of this disclosure is to provide an extremely light, highly sophisticated and superior strength ruggedized enclosure better suited for protecting, housing, and transporting environmentally sensitive electronic equipment particularly use in military settings. 
     PATENTED PRIOR ART 
     U.S. Pat. No. 4,741,972 to Hardigg 
     U.S. Pat. No. 4,998,636 to Hardigg 
     U.S. Pat. No. 5,370,254 to Hardigg et al. 
     U.S. Pat. No. 5,416,284 to Steele et al. 
     U.S. Pat. No. 5,808,866 to Porter 
     U.S. Pat. No. 5,873,480 to Wells, Jr. 
     U.S. Pat. No. 6,158,745 to Deighton 
     U.S. Pat. No. 6,203,075 to Wells, Jr. et al. 
     U.S. Pat. No. 6,622,881 to Hardigg 
     U.S. Pat. No. 6,698,608 to Parker et al. 
     U.S. Pat. No. 6,953,126 to Parker et al. 
     U.S. Pat. No. 6,955,381 to Parker et al. 
     U.S. Pat. No. 7,312,984 to Richardson et al. 
     U.S. Pat. No. 7,533,782 to Parker et al. 
     U.S. Pat. No. 7,724,513 to Coglitore et al. 
     U.S. Patent Application Publication 2006/0289470 to Sparague et al. 
     U.S. Patent Application Publication 2007/0245651 to Hardigg et al. 
     U.S. Patent Application Publication 2009/0178946 to Patstone et al. 
     U.S. Patent Application Publication 2009/0200300 to Parker et al. 
     U.S. Design Pat. D327,646 to Hardigg 
     U.S. Design Pat. D357,180 to Stover 
     U.S. Design Pat. D439,407 to Parker 
     U.S. Design Pat. D441,954 to Parker 
     U.S. Design Pat. D462,519 to Gaydos et al. 
     U.S. Design Pat. D464,196 to Parker 
     U.S. Design Pat. D465,330 to Parker 
     U.S. Design Pat. D467,424 to Hardigg et al. 
     U.S. Design Pat. D467,425 to Hardigg et al. 
     U.S. Design Pat. D467,426 to Hardigg et al. 
     U.S. Design Pat. D482,529 to Hardigg et al. 
     U.S. Design Pat. D523,242 to Hardigg et al. 
     U.S. Design Pat. D530,917 to Conforti 
     The foregoing examples of the related art and limitations related therewith are intended to be illustrative and not exclusive. Other limitations of the related art will become apparent to those skilled in the art upon a reading of the specification and a study of the drawings. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention is directed to a ruggedized case for transportation and protection of electronic equipment used in hash commercial or military environments. The ruggedized case is 30-70% lighter than other similar competing cases through the use of lightweight, low-density, superior strength composite materials. The ruggedized case includes a multi-panel case body open at each end and two removable covers. A chassis which may be vibration and shock isolated, and a removable rack mount frame are also provided. Each component of this ruggedized case, including recessed cover latches, and handles, weather and airtight seals, adjustable rack mount frame lock mechanisms, and vibration isolators, have been significantly improved to provide more ergonomic form and functionality. This construction is also non-deforming under temperature extremes, chemical resistant, robust stacking characteristics integrated into the case body itself. The preferred materials and processing methodology incorporate continuous carbon fiber reinforced thermoplastics from either Bond Laminates GMBH or Schappe Technique of France. 
     A beneficial feature of the ruggedized transit case of this invention is lightweight. The present design will be 30-70% lighter than any other similar cases through the use of lightweight, low-density structural composite materials. In this invention, the density of the continuous carbon fiber reinforced thermoplastic materials will be approximately 0.05896 lbm/in 3  which translates into nearly a 50% weight savings over aluminum while providing far greater design flexibility and substantially increasing the structural rigidity of the enclosure components. 
     Since continuous carbon fiber reinforced composite materials exceed the structural properties of aluminum in the same thickness, part thickness is decreased thereby reducing the weight even further. Enclosure wall thicknesses will be up to 0.25″ thinner than those of roto-molded competitors&#39; products. Composite to composite bonding or joining of components may be done through traditional methods such as by gaskets and fasteners, structural glue or epoxy, ultrasonic welding, vibration welding, in-situ molding processes, co-molding, or two shot molding. 
     It is an object of the present invention to provide a removable rack mount frame for a case, which is capable of supporting electronic equipment and modules within the case to prevent damage caused by impacts and vibration. 
     It is another object of the present invention to provide a rotation lock mechanism for a case wherein the removable frame is retained to the chassis by dual rotation lock mechanisms at both sides of the enclosure visible only when the top or bottom wall is off; the lock mechanism can be rotated, therefore releasing and relocking the removable frame in multiple indexed positions and also allowing secure access to the suspended electronics without complete removal from the transit case. 
     It is another object of the present invention to provide recessed cover latches for a case which sit flush when not in use with no sharp edges capable of cutting or snagging a passerby. The recessed latch permits rapid opening of the sealed cased and rapid reinstallation and resealing of cover to the case body. 
     It is another object of the present invention to provide spring loaded handles for a case which are ergonomically designed to allow swiveling on axis up to 180° and rotating outward from a flush recess to a 90° position, and automatic rotating back to a non-use position once released from use. Articulating handles facilitate maneuvering of the case through tight openings while the ergonomic design allows for enhanced management of centers of gravity. 
     It is another object of the present invention to provide an improved means for sealingly connecting the outer panels together mechanically to form a sealed interior volume of the housing assembly. 
     It is another object of the present invention to provide a weight reduced chassis that includes eight shock absorbers symmetrically positioned between the framework of the chassis assembly and the wall of the ruggedized case, wherein the shock absorber is located in a 45° orientation at each one of 8 corner locations. 
     It is still another object of the present invention to use light-weight, superior strength composite materials to fabricate the case, all panels being constructed from high pressure compression molded polymer composite, which consists of 70˜30% by volume continuous carbon fiber, and 30˜70% by volume PA 6,6 resin. 
     The instant invention is further described with reference to the accompanying drawings. Other features and the advantages of the invention will be apparent from the following detailed description of the preferred embodiment. 
     The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative and not limiting in scope. In various embodiments one or more of the above-described problems have been reduced or eliminated while other embodiments are directed to other improvements. In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following descriptions. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         FIG. 1  is a perspective view of the ruggedized composite rack mount transport case  10  according to the invention. 
         FIG. 2   a  is a perspective view of the case cover  14  of  FIG. 1 ; 
         FIG. 2   b  is a bottom plan view of  FIG. 2   a.    
         FIG. 2   c  is an exploded perspective view of  FIG. 2   a.    
         FIG. 3   a  is a perspective view of the cover latch  22  of  FIG. 1 ; 
         FIG. 3   b  is an exploded view of  FIG. 3   a.    
         FIG. 4   a  is a top plan view of the cover parting bracket  48  and blade  50  of  FIG. 2   a.    
         FIG. 4   b  is a broken side perspective view of  FIG. 4   a.    
         FIG. 5  shows an exploded view of the case body  12  of the ruggedized composite rack mount transport case. 
         FIG. 6   a  is a perspective view of panel  56 -A. 
         FIG. 6   b  is a perspective view of panel  56 -B. 
         FIG. 7   a  is a front perspective view of the case handle  16 . 
         FIG. 7   b  is a rear perspective view of the case handle  16 . 
         FIG. 7   c  is an exploded perspective view of the handle  16 . 
         FIG. 8   a  is a plan view of rotary housing  130  of case handle  16 . 
         FIG. 8   b  is a lower perspective view of  FIG. 8   a.    
         FIG. 9   a  is a plan view of the parting bracket  66  and gasket  122  of case body. 
         FIG. 9   b  is a broken side perspective view of  FIG. 9   a.    
         FIG. 9   c  is an enlarged view of area  9   c  in  FIG. 9   b.    
         FIG. 10   a  is a vertical section view of  FIG. 1 . 
         FIG. 10   b  is an enlarged view of area  10   b  in  FIG. 10   a.    
         FIG. 11   a  is a perspective view of the removable rack mount frame  70 . 
         FIG. 11   b  is an enlargement of area  11   b  in  FIG. 11   a.    
         FIG. 11   c  is an enlargement of area  11   c  in  FIG. 11   a.    
         FIG. 11   d  is an exploded perspective view of  FIG. 11   a.    
         FIG. 12  is an exploded perspective view of lock mechanism  100 . 
         FIG. 13  shows lock mechanism  100  attached to each end of one piece of chassis  69 . 
         FIG. 14   a  is a top plan view of the chassis  69 , removable rack mount frame  70 , and lock mechanism  100  and vibration/shock absorber  98 . 
         FIG. 14   b  is a perspective view of  FIG. 14   a.    
         FIG. 14   c  is an enlargement of area  14   c  in  FIG. 14   b.    
         FIG. 14   d  is a view of  FIG. 14   a  showing removal of the rack mount frame  70 . 
         FIG. 15  is a partial exploded perspective view of vibration/shock absorber  98 . 
     
    
    
     Exemplary embodiments are illustrated in reference figures of the drawings. It is intended that the embodiments and figures disclosed herein are to be considered to be illustrative rather than limiting. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Nomenclature 
     
         
           10 . ruggedized case assembly 
           12 . case body 
           14 . removable cover 
           16 . handle 
           21 . air pressure relief valve 
           22 . cover latch 
           24 . T-handle 
           26 . latch cap 
           28 . latch sleeve 
           32 . hex nut 
           34 . spring 
           36 . O-ring 
           40 . latch rivet 
           42 . latch pin 
           44 . recessed cup 
           46 . cam 
           48 . cover parting bracket 
           50 . cover parting blade 
           52 . nut 
           54 . cover panel 
           56 A. panel 
           56 B. panel 
           58 . corner panel 
           60 . side panel 
           62 . plate 
           64 . locker 
           66 . case body parting bracket 
           68 . parting guide 
           69 . chassis 
           70 . rack mount frame 
           72 . frame member 
           74 . corner joint 
           76 . frame slide member 
           78 . C-channel rail 
           80 . slide 
           82 . slide 
           84 . adjustable mounting rail 
           86 . stop bracket 
           90 . steel plate 
           94 . steel plate 
           98 . vibration/shock absorber 
           99 . shock absorber bracket 
           100 . lock mechanism 
           101 . shock absorber bracket 
           102 . lever 
           103 . isolator 
           104 . flange sleeve 
           106 . locker shaft 
           108 . locker 
           110 . pivot bracket lock 
           112 . locking flange 
           113 . jam nut 
           114 . extension spring 
           115 . threaded fastener 
           122 . gasket 
           126 . threaded fastener 
           128 . cartridge bearing 
           130 . rotary housing 
           132 . ferrule 
           134 . spring 
           136 . long rivet 
           138 . small spring 
           140 . center 
           144 . handle base 
       
    
       FIG. 1  shows a perspective view of a preferred embodiment at numeral  10  according to the present invention. The ruggedized transit case  10  is preferably formed in the shape of rectangular assembly and constructed from a case body  12  and two removable covers  14 . As shown in  FIG. 1 , the body  12  is formed from the panels  56  A and B, side panels  60  and corner panels  58  which serve to connect the panels  56  and panels  58 , and body parting bracket  66 , parting guide  68 , gasket member  122  and chassis  69  and removable rack mount frame assembly  70 . The center body parting line edge is preferably adapted to align with the parting line of the cover, as will be discussed below. The panels  56  A and B are provided with a plurality holes which receive rivets that are used to hold the corner panels  58  in mating engagement with panels  56  and sides panel  60 . The surrounding walls of both case body  12  and covers  14  are preferably made of continuous carbon fiber reinforced polyamide 6,6 composite (PA6,6) composites by compression mold techniques. 
     Case Removable Cover 
       FIGS. 2   a - c  show various views of the removable cover  14 . The case covers  14  are removable and comprised of a cover panel  54  having a cover parting bracket  48  and cover parting blade  50 . The periphery and surface are made from the same continuous carbon fiber reinforced PA 6,6 composite by compression mold techniques. Four two-stage positive latches  22  are attached to the cover through the recessed cups  44 , which are joined to the covers by conventional fasteners, such as structural glue or epoxy (not shown). As shown in  FIG. 2   c , the latch  22  is uniquely implemented to accommodate hands even wearing chemical gloves. A cam  46  is locked onto the end of each latch by two nuts  52 . The cover is sealedly attached to the center body  12  through four latches by the interaction between the cam  46  and lockers  64  which are attached to cover parting bracket  48  of the case body  12 . 
     In circumstances which result in the heating of the interior volume by the electronic equipment contained therein or by the increased exterior environmental temperature and which might otherwise cause excess static pressure to build within the interior volume to threaten the integrity of the sealing members of this invention as described previously. A spring loaded air pressure relieve valve  21  is mounted on one surface of the removable cover (see  FIG. 1 ). The valve  21  permits for ingress and egress of the pressure to equilibrate the pressure between the inside and the outside of the case. 
     Materials/Weight Reduction 
     The preferred material and processing technique of this design are continuous carbon fiber reinforced polyamide 6, 6 (PA 6,6) composite from either Bond Laminates GMBH or Schappe Technique of France by thermoforming/stamping techniques. The composite is a sandwich structure which includes carbon fiber or carbon fiber combined glass fiber in the structure. The composite material includes 30˜70% by volume continuous fiber, and 70˜30% by volume PA 6,6 resin. 
     The thermoplastic resins used in the composites structure are not limited to PA 6,6, but may include polyethylene (PE), polyamide 6 (PA6), polyamide 12 (PA 12), polyimide (PI), polycarbonate (PC), poly(methyl methacrylate) (PMMA), poly (ethyleneterephtatlate) (PET), polypropylene (PP), poly (butylene terephthalate) (PBT), polystyrene (PS), polyurethane (PU), polyacrylonitri (PAN), Acrylonitrile Butadiene Styrene (ABS) and so on. 
     Composites preferred are selected from the group of composites comprising essentially continuous carbon fiber, carbon fiber reinforced thermoplastics; and combinations thereof. The process used for the manufacturing of the case panels and covers is thermostamp molding at a pressure of 1000˜4000 psi; the processing temperature is at a temperature above the melting point of the polymer. The carbon fiber reinforced thermoplastics are heated to a temperature above melting point for 1˜3 min and thermostamped under a compressive pressure of 1000˜4000 psi in the mold. The mold is unloaded for 1˜2 min. to cool the part to ambient temperature. 
     Comparison of weight between conventional aluminum and carbon fiber reinforced polymer composites of this invention shows the lightweight and superior strength of continuous carbon fiber reinforced thermoplastics (such as PA6,6) used for the transit case assembly  10 . The density of this material is approximately 0.059 lbs./in 3 , which is much less than that of aluminum (0.097 lbs/in 3 ). The thickness of the continuous carbon fiber reinforced thermoplastics will be in the range of 0.5˜3 mm. Since continuous carbon fiber reinforced composite materials exceed the structural properties of aluminum in the same thickness, case component thickness is decreased thereby reducing the weight even further. This translates to nearly a 50% weight savings over aluminum while providing far greater design flexibility, sophistication and substantially increasing the structural rigidity of the present invention. Compared with conventional roto-molded or glass-mat thermoplastic competitors&#39; cases where the case wall thickness is up to 0.25″, the present invention provides still greater weight reductions. 
     Two Stage Air and Water-Tight Latch 
     The present invention takes advantage of the construction of a recessed cup  44  and the two-stage positive latch  22 . The latch  22  is uniquely implemented to accommodate hands even wearing chemical gloves. The recessed latch  22  permits rapid opening of case assembly  10  and also rapid reinstallation and resealing of each cover  14  to the case body  12 . The cover latch  22 , as shown in  FIG. 2   a , sits flush when not in use with no sharp edges capable of cutting or snagging a passerby.  FIG. 3   b  is the exploded view of the latch  22  and comprises a T-handle  24  made of aluminum, a latch pin  42 , a latch sleeve  28 , a spring  34  coupled to a sleeve  28 , a latch cap  26 , a hex nut  32 , a latch rivet  40 , and a latch pin  42 . The latch pin  42  traverses through other lathe parts and inserts into T-handle  24 . The O-ring  36  is used to conform to the space between the latch pin  42  and latch sleeve  28  to provide sealing between the two components. O-ring  30  is also coupled to the end of the latch cap  26  providing tight sealing arrangement between the nut  32  and cap  26 . During practical application, the T-handles  24  are deployed by rotation outward 90° (step I in  FIG. 3   b ), and swiveling on axis 90° (step II in  FIG. 3   b ), then they automatically simultaneously rotate the cam  46  out of the way thereby releasing the cover  14  from the case body  12 . 
     Cover Parting Bracket and Parting Blade 
     The cover parting bracket  48  and parting blade  50  are shown in  FIGS. 4   a  and  b . The cover parting bracket  48 , made of glass fiber reinforced PA-6 composite material by compression mold techniques, is tightly connected against the inner side surface of the cover  14 , as shown in  FIG. 1 . The inner surface of the cover parting bracket  48  is recessed on a vertical portion for reduction of the weight, as shown in  FIG. 4   a . In order to establish the sealing engagement between the cover  14  and case body  12 , a bracket blade  50 , made of aluminum, is connected to the cover parting bracket  48  (as will be further described below). A plurality of rivets is used to hold the cover parting bracket  48  and the bracket blade  50  together attached to the periphery of cover panel  54 . This engagement of the formation of cover parting acts to keep the case body  12  and cover  14  in closure relationship so that the transit case can be sealed in water-tight and also air-tight engagement during practical applications. 
     Case Body 
     In  FIG. 5 , the case body  12  is formed of panels  56  A and B, side panels  60 , four corner panels  58  and case body parting bracket  66 , gasket  122 , parting guides  68 , chassis  69 , and removable rack mount frame assembly  70 . It is an important aspect of the present invention that the ruggedized case assembly  10  is capable of stacking one case assembly atop of another case assembly. The top and bottom surfaces (panel  56  A and B) of the case body  12  as shown in  FIGS. 6   a  and  6   b , have molded male and female features that allow stackability of ruggedized composite rack mount cases, which could prevent side-to-side slippage between the two cases in all directions. 
     Ergonomically Designed Handle 
     Referring to  FIGS. 7   a  to  7   c , two handles  16  for pulling or carrying the case are located on each of the two side panels  60  and recessed below the exterior surface. This is another important aspect of the present invention that the handles  16  are spring loaded and ergonomically designed and will swivel on axis up to 180° and rotate outward from a flush recess to a 90° position, automatically rotating back into a home position once released from use. 
     The handle  16  includes a center  140  made of aluminum, rotary housing  130 , spring  134 , handle base  144 , two sealed cartridge bearings  128  and ferrule  132 . The rotary housing  130  is made of aluminum with a channel (different diameters) located at the center of the housing, as shown in  FIG. 8   a . The ferrule  132  is inserted into the central portion of the channel and two sealed cartridge bearings  128  are symmetrically inserted into the channel from both sides, and then the spring  134  is attached on the channel of rotary housing  130  as shown in  FIG. 8   b.    
     A long rivet  136  attached with a small spring  138  is recessed into handle  16  center  140 , which is used to hold the rotary housing  130  and  140  in mating engagement (see  FIG. 7   c ). This construction will allow the handle  16  to rotate outward from a flush recess to 90° position, and automatically rotate back into a home or at rest position. The handle base  144  is firmly secure to the panel  60  by two threaded screws. Two Hex nuts are tightly locked on the end of the threaded screws preferably against the plate  62 . A threaded fastener  126  traverses through the ferrule  132  and the cartridge bearing  128  through which the handle  16  is pivotally mounted to the panel  60 . A Hex nut is lockingly engaged onto the end of the threaded fastener  126  preferably against a plate  62  for more uniform compression as shown in  FIG. 5 . The handle  16  is allowed to swivel on axis of up to 180°. 
     Case Body Parting Bracket and Gasket 
     Turning now to  FIGS. 9   a  to  9   c , the case body parting bracket  66  and gasket  122  are shown. The case body parting bracket  66 , made of continuous carbon fiber reinforced PA 6 polymer composite, is connected around the ends of the surrounding panels (wall) of the case body  12  utilizing rivets. Two functions are afforded by the case body parting bracket  66 : to strengthen the case construction and provide enhanced impact resistance and durability during rough shipping and handling. Another function is to allow the case body  12  to effectively accommodate the cover  14 . In order to further strengthen the construction, eight parting guides  68  ( FIG. 10   b ), made of UHMW polyethylene are affixed at four corners and middle of the case body parting bracket  66 . 
     In order to establish secure sealing contact between the case body  12  and each cover  14 , a rubber gasket  122  is shaped to conform tightly within the slot of the case body parting bracket  66 , as shown in  FIGS. 9   c  and  10   b . The thickness and width of the gasket  122  are precisely consistent with the thickness and width of the slot of the case body parting bracket  66 , respectively. 
     When the cover  14  is assembled to the case body  12 , the cover parting blade  50  of the parting bracket  48  aligns with, and compresses the gasket  122  of the case body parting bracket  66  as shown in  FIGS. 10   a  and  10   b . This engagement acts to keep the body  12  and cover  14  in a sealed closure relationship so that the transit case  10  can be kept in sealed water-tight and air-tight engagement to provide protection to the electric equipment from moisture, salt spray, dust, oils, solvents and other military environments. 
     Removable Rack Mount Frame 
       FIGS. 11   a - d  illustrate the removable rack mount frame  70  which is constructed of aluminum and preferably rectangular in shape in order to be accommodated within the similarly-shaped case  10 . It can be seen from  FIG. 11   a  that the rack mount frame  70  includes four frame members  72 , eight corner joints  74  and two frame side members  76  having a horizontal portion and a vertical portion. The ends of each U-shaped member  72  and frame side members  76  are connected together by a corner joint  74 , which is made of machined aluminum. The corner joint  74  is inserted into frame member  72  (see  FIGS. 11   b  and  11   c ). In order to further strengthen the construction, four countersunk rivets pass through the unthreaded holes of the corner joint  74  and through four aligned unthreaded holes of the frame side member  76 . Two countersunk rivets pass through the unthreaded holes of the U-shaped member  72  and through the aligned holes of the corner joint  74  as shown in  FIGS. 11   b  and  11   c.    
     As illustrated in  FIGS. 11   b ,  11   c  and  11   d , C-channel mounting rails  78  are attached on the horizontal portion of frame side member  76 . The C-channel mounting rail  78  has two flanges with different lengths with the longer flange being positioned on the outer surface of the horizontal portion of frame side member  76 . Five rivets pass through the unthreaded holes of the C-channel rail  78  in the horizontal direction and then pass through the aligned holes of the horizontal portion of frame side member  76  to firmly secure the C-channel rail  78  to the frame side member  76 . 
     Two steel plates  90  and  94  with different lengths are correspondingly positioned on the inner surface of the two flanges of the C-channel rail  78 , respectively. Two threaded holes with different diameters are drilled on the surface of each steel plate  90  and  94 . The small size holes are used to secure the steel plate to the C-channel rail  78 . The spacing between adjacent parallel holes on each steel plate  90  or  94  is equal to the spacing between adjacent parallel holes on the corresponding flange of the C-channel rail  78 . Five screws pass through the holes on the outer surface of the flange of C-channel rail  78  in the vertical direction and thread into the aligned holes on each steel plate  90  and  94 , which secures the steel plates  90  and  94  to the corresponding C-channel flange. The advantageous cooperation between C-channel rail  78  and steel plates  90  and  94  secures the front bezel panel of electronic equipment and modules to the removable rack mount frame  70 . 
     In addition, the present invention preferably provides an adjustable advantage for the attached electric equipment and modules. An adjustable mounting rail  84  is positioned intermediate to each frame side member  76 , as shown in  FIG. 11   a . Two threaded fasteners pass through the unthreaded holes at the end of each mounting rail  84  and through the aligned unthreaded holes on the vertical portion of frame side member  76 . A hexagonal nut is lockingly engaged onto the end of the threaded screw for securing the mounting rail  84  to the vertical portion of frame side member  76 . Each adjustable mounting rail  84  can be positioned as desired lengthwise of the frame side member  76  to allow for the advantageous mounting of the electric equipment. This unique feature provides variable equipment mounting capabilities in accordance with the size of the electric equipment. 
     Four longitudinal slides  82 , preferably made of UHM polyethylene, are symmetrically mounted on the outer surface of vertical portion of frame slide member  76  in a 45° orientation at the four corner locations as shown in  FIGS. 11   b  and  11   c . The rack mount frame  70  is slidable and removable, slides  82  serving to facilitate the smooth sliding movement of the removable rack mount frame  70  into, and out of the case  10 . In  FIG. 11   d , it can be seen that the slides  80  are also symmetrically mounted on the inner surface of the vertical portion of frame slide side  76 . Each slide  82  is located at the corner and closely connected to U-shaped members  72 , which facilitates the sliding of the electric equipment into and out of the removable frame  70 . As seen in  FIG. 11   d , four pins  88  are inserted into alignment holes of each corner joint  74 . When the removable frame  70  is slid into the chassis  69 , the pins  88  will insert into aligned holes in the chassis  69  for additional alignment accuracy and stability. 
     Lock Mechanism for Removable Rack Mount Frame 
     The lock mechanism  100  is a unique design in the present invention. It comprises lever  102 , two flange sleeves  104 , locker shaft  106 , locker  108 , locking flange  112 , pivot bracket lock  110 , as shown in  FIGS. 12 and 13 . The locker  108  is tightly mounted to the locker shaft  106  through pin  103 . Each end of locker shaft  106  is inserted into the lever  102  and locking flange  112 , respectively, and each end is fixed by another pin. The flange sleeve  104  is coupled to the locking flange  112  and lever  102 , respectively, and extend through the hole on the pivot bracket lock  110 , whereby the pivot bracket lock  110  is attached to the locker shaft  106 . An extension spring  114  is attached to the lock mechanism through a hole on the pivot bracket lock  110  and the threaded fastener  115 , which are screwed into the hole on the locker  108 . A jam-nut  113  is engaged onto the threaded fastener  115  preferably against the locker  108  which is used to control longitudinal positioning of locker  108 . The lock mechanism  100  is mounted to the chassis  69  by the pivot bracket lock  110  by two screws which secure the lock mechanism  100  to the chassis  69 . Meanwhile, the locker shaft  106  of lock mechanism also traverses through the hole on the edge of chassis  69  as shown in  FIG. 13 . 
     Four stop brackets  86 , as shown in  FIGS. 11   b  and  11   c , are connected to the outer surface of the vertical portion of frame side member  76 . Multiple positions are provided by each of four stop brackets  86  and serve to selectively accommodate the lock mechanism  100  as will be described below. 
       FIGS. 14   a - d  show the chassis  69 , removable rack mount frame  70 , and lock mechanism  100 . The removable rack frame  70  is retained in chassis  69  by the four lock mechanisms  100  by the interaction between the stop bracket  86  and locker  110  of lock mechanism  100 . The lock mechanism  100 , as shown in  FIGS. 14   b  and  14   c , can be rotated 90° in the direction of arrow A releasing (or relocking) the removable rack mount frame  70  from the chassis  69  (see  FIG. 14   d ). Meanwhile, the stop bracket  86  connected to the removable rack mount frame  70  has multiple indexed positions via the interaction between the stop bracket  86  and locker  108  of each lock mechanism  100 . The lock mechanisms  100  secure the removable rack mount frame  70  to the chassis  69  during shipping or handling of the case  10  and also prevent the removable rack mount frame  70  from any destructive movement when the case  10  is dropped, or suffers some other type of impact, incident force, or the like. With one cover  14  removed, the suspended electronic equipment is accessible without complete removal of the removable rack mount frame  70  from the case  10 , thereby permitting the user to pack, unpack or manipulate the electric equipment within the removable frame  70  without the interference caused by case  10 . 
     Vibration/Shock Absorbers 
     As best seen in  FIGS. 14   c ,  14   d  and  15 , vibration/shock absorbers  98  are symmetrically mounted between the outer corners of the chassis  69  and the inner corners of the case body  12  in a 45° orientation. The vibration/shock absorber  98  is made of aluminum having two shock absorber brackets  99  and  101  and isolator  103  as shown in  FIG. 15 . The shock absorber brackets  99  and  101  are mounted to panel  58  and the chassis  69 , respectively, which will secure the chassis  69  to the case body  12  during the transportation of the case body  12  and also provide shock and vibration attenuation during corner drop testing and practical application. 
     In the preferred embodiment, eight (8) vibration/shock absorbers  98  are symmetrically mounted between the outer chassis  69  and the surrounding panels of the ruggedized composite case  10  in a 45° orientation as previously described and provide shock and vibration attenuation for electronic equipment of all types. However, in another embodiment, the case may be provided without vibration/shock absorbers  98 . The chassis  69  will be directly mounted onto the surrounding panels of case body  12  through fasteners. 
     EMI/RFI Shielding 
     Electromagnetic interference shielding (EMI) and radio frequency interference (RFI) may cause malfunctions in electronic devices in a ruggedized composite rack mount transport case. In order to prevent EMI or RFI, EMI/RFI shielding agents may be employed and will be coated on the interior surface of the surrounding panels  56 A,  56 B and  60  and corners  14  of the case  10  through thermoforming/stamping techniques, which will reduce or completely eliminate EMI and RFI interference. The EMI/RFI shielding agents may be selected from the group including metal mesh or foil including copper, nickel and silver; copper or nickel coated carbon fiber or glass fiber, and combinations thereof. 
     Many advantages of the present invention can be clearly seen from the preferred embodiments described. It will be understood by those skills in the art that various modifications may be made within the scope of the invention. Therefore, it is intended that the invention is not be limited to the particular embodiments disclosed, but that the invention includes all embodiments falling within the scope of the appended claims. 
     While a number of exemplary aspects and embodiments have been discussed above, those of skill in the art will recognize certain modifications, permutations and additions and subcombinations thereof. It is therefore intended that the following appended claims and claims hereinafter introduced are interpreted to include all such modifications, permutations, additions and subcombinations that are within their true spirit and scope.