Patent Publication Number: US-8978392-B2

Title: Thermoelectrically air conditioned transit case

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. Ser. No. 11/997,362, filed Jul. 8, 2008, which is the National Stage of International Application No. PCT/US2005/043702, filed Dec. 2, 2005, which claims the benefit of U.S. Provisional Application No. 60/705,680, filed Aug. 4, 2005, and U.S. Provisional Application No. 60/727,736, filed Oct. 18, 2005, each of which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to thermoelectrically air conditioned cases. More specifically, the present invention relates to, thermoelectric air conditioners for use with, and mounted on or in, a transit case for maintaining a desired air temperature within the transit case to protect temperature sensitive equipment, such as electrical and electronic devices. 
     BACKGROUND 
     Transit cases exist to house and protect equipment during shipment from one location to another location and during temporary use of the equipment at remote locations. These transit cases are also sometimes referred to by other and different names, such as: Transit Case; Dry Case; Rotomold Case; Rotomolded Case; Rotationally Molded Case; Injection Molded Case; Utility Case; Transport Case; Transportation Case; Travel Case; Rack Case; Rackmount Case; Shock-Rack Case; Blow Molded Case; Vacuum Molded Case; Shipping Case; Storage Case; Military Case; Waterproof Case; Engineered Case; Computer Case; and ATA (Airline Travel) Case. 
     These cases are typically produced of the following materials: Rotomolded PE (polyethylene); Injection molded ABS; Fiberglass (FRP); Thermo Stamped Composite (TSC), which is glass-reinforced polypropylene; Aluminum; Steel; Stainless Steel, and other materials. 
     These cases are manufactured by a number of different firms. A few of the manufacturers in this industry include: Hardigg Industries, Inc., South Deerfield, Mass. (see www.hardigg.com); ECS Composites Inc., Grants Pass, Oreg. (see www.ecscase.com); SKB Corp., Orange, Calif. (see www.skbcases.com); Zero Manufacturing Inc., North Salt Lake, Utah (see www.zerocases.com); Pelican Products, Inc., Torrance, Calif. (see www.pelican.com); Quantum Scientific, Ontario, Canada (see www.cyber-case.com); Ameripack Corporation, Robbinsville, N.J. (see www.ameripack.com). 
     These cases are designed to house and protect equipment. The equipment can include items such as electronics, instrumentation, computers, telecommunications gear, and the like. Protection is provided during transit, storage and operation of the equipment. The cases are typically designed to protect the equipment contained within the case from one or more of the following elements (list is not all-inclusive): heat; dirt; dust; debris; vandalism; shock; vibration; dropping; moisture; rain; snow; sleet; hail; ice; cold; and the like. 
     Depending on the style and construction of the case, many cases can handle one or more of the above needs. But, most, if not all, have difficulty handling heating and cooling requirements of the internal equipment during transportation, storage, and operation. Since most cases are airtight (or substantially airtight), if electronics are contained within the case, there is often heat build-up. Also, if the case is outdoors, and especially if the case is outdoors and in direct sunlight, heat build-up can be excessive, causing damage or failure to the equipment within the case. 
     Conventional solutions to the above heat problem include fans, holes, openings, louvers, etc. in or on the case. These solutions to the heat problem, however, then cause the case to give up its ability to protect against other elements, such as dirt, dust, other contaminants, etc. In addition, these solutions can not drive the temperature within the case below ambient. 
     Another conventional solution is to install a heat exchanger in or on the case. But conventional heat exchangers can not drive the temperature within the case below ambient. 
     If the goal is to drive the temperature within the case below the ambient temperature, this can best be done utilizing an air conditioner. Most air conditioners are the traditional compressor-based type. Since traditional compressor-based air conditioners have a compressor, they are somewhat larger in size and heavier in weight than desired. In addition, traditional compressor-based type air conditioners must remain in one orientation (typically vertical). Also, compressor-based air conditioners include additional components, such as refrigerants and filters, and require regular maintenance. Further, most compressor-based coolers are AC-powered (120 VAC or 240 VAC), are not easily or readily portable, and have other disadvantages when considered for use with a transit case. 
     SUMMARY 
     The present invention is directed to systems and methods for maintaining a desired air temperature within a portable case, such as a transit case, using a thermoelectric heat exchanger. 
     According to one preferred embodiment of the present invention, a thermoelectric air conditioner is mounted on or in a transit case for cooling the contents (typically sensitive equipment or systems) within the transit case. 
     According to another aspect of the invention, a light-weight and compact thermoelectric air conditioner is used. A thermoelectric solid state air conditioner provides advantages over conventional compressor-type air conditioners in that a thermoelectric air conditioner has no compressor, refrigerants or filters and provides reliable, virtually maintenance-free cooling in both indoor and outdoor applications. 
     According to another aspect of the invention, the thermoelectric air conditioner is incorporated into the case, concealed within the housing and/or cover of the transit case. In this embodiment, the thermoelectric air conditioner is protected by the design of the case, the mounting arrangement, the shock-mounted frame, etc. 
     According to another aspect of the invention, the thermoelectric air conditioner is mounted partially internal and partially external to the transit case. 
     According to another aspect of the invention, the thermoelectric air conditioner is mounted to the top and/or side of the transit case. 
     According to another aspect of the invention, more than one thermoelectric air conditioner are installed in or on the case. 
     According to another aspect of the invention, insulation is installed within the transit case. Insulation reduces thermal heat transfer between the interior and the exterior of the case. The addition of insulation can also reduce solar loading on the case and heat penetration into the case, providing for greater reduction of internal temperatures. 
     According to another aspect of the invention, an adapter plate can be used to “close the gap” between the edges of the thermoelectric air conditioner mounting flange and the internal sides of the transit case. The adapter plate preferably includes a seal or gasket that forms a boundary between the thermoelectric air conditioner and the case. This further enhances the ability of the transit case to maintain, as close as possible, an airtight status and seal out moisture, dirt, sand, etc. thus substantially preventing these contaminants from entering the interior of the case. 
     According to another aspect of the invention, an extender piece or extension frame can be used to flush mount the thermoelectric air conditioner to the case when, for example, the entire internal cavity of the case is needed to house the equipment. 
     According to another aspect of the invention, the thermoelectric air conditioner is removably mounted on the case such that it can be mounted on the case during operation or stowed away in the case during transit. 
     According to another aspect of the invention, the thermoelectric air conditioner is housed within a secondary case and the equipment is housed within a primary case. During operation, the covers of the primary and secondary cases are removed such that the primary and secondary cases can be connected and can be in thermal communication. During transit, the primary and secondary cases can be disconnected and the covers can be replaced such that the equipment and thermoelectric air conditioners are protected. In one embodiment, the primary case and the secondary case are mounted end to end, and in another embodiment the primary case and the secondary case are mounted one on top of the other. 
     According to another aspect of the invention, a rack mounted frame can be installed in the cavity of the case. In this embodiment, the equipment and thermoelectric air conditioners can be mounted on the rack mount frame to balance the load on the frame and make it easier to handle the case. In addition, the rack mount frame can be supported by elastomer shock mounts attached to the walls of the case to protect the equipment mounted in the case and help absorb shock, vibration, noise, etc. 
     According to another aspect of the invention, the thermoelectrically air conditioned transit case is designed for easy handling. In one embodiment, the case is fitted with wheels so that the case may be easily moved around. In another embodiment, the thermoelectrically air conditioned transit case is fitted with handles that are located in grooves or recesses in the housing and are positioned within the groove or recess when not in use and are accessible or capable of moving out of the groove or recess when in use. In another embodiment, the thermoelectrically air conditioned transit cases may be stacked end-to-end and/or one on top of another. In this embodiment, the housing of the case may include a shoulder and slot design wherein the shoulder of one case would be received within a corresponding slot of an adjoining case. 
     Additional features and advantages of the invention will be made apparent from the following detailed description of illustrative embodiments that proceeds with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is best understood from the following detailed description when read in connection with the accompanying drawing. It is emphasized that, according to common practice, various features of the drawings are not to scale. On the contrary, the dimensions of various features are arbitrarily expanded or reduced for clarity. Included in the drawings are the following Figures that show various exemplary embodiments and various features of the present invention: 
         FIG. 1  shows a perspective view of an exemplary thermoelectrically air conditioned transit case having a thermoelectric air conditioner vertically mounted internal to the transit case with the transit case front cover removed for clarity; 
         FIG. 2  is a side view of the thermoelectrically air conditioned transit case of  FIG. 1 ; 
         FIG. 3  is an end view of the thermoelectrically air conditioned transit case of  FIG. 2 ; 
         FIG. 4  is an exploded view of the exemplary thermoelectrically air conditioned transit case of  FIG. 1 ; 
         FIG. 5  shows a perspective view of another exemplary embodiment of a thermoelectrically air conditioned transit case having the thermoelectric air conditioner horizontally mounted internal to the transit case with the transit case top cover opened for clarity; 
         FIG. 6  is an exploded view of the exemplary thermoelectrically air conditioned transit case similar to the embodiment of  FIG. 5 ; 
         FIG. 7A  is a perspective view of another exemplary embodiment of a thermoelectrically air conditioned transit case having a thermoelectric air conditioner through-mounted with at least a portion of the thermoelectric air conditioner being internal to the transit case; 
         FIG. 7B  is a perspective view of the embodiment of  FIG. 7A  with the thermoelectric air conditioner flush-mounted to the case; 
         FIG. 8  is a perspective view of another exemplary embodiment of a thermoelectrically air conditioned transit case having an external, horizontal, through-mounted thermoelectric air conditioner; 
         FIG. 9A  is an exploded view of an exemplary thermoelectrically air conditioned transit case similar to the embodiment of  FIG. 7A , wherein the thermoelectric air conditioner is removably mounted; 
         FIG. 9B  shows the thermoelectric air conditioner of  FIG. 9A  removed and stowed in the transit case; 
         FIGS. 10A-10D  show features of another exemplary thermoelectric air conditioned transit case; 
         FIG. 11  is a perspective view of another exemplary embodiment of a thermoelectric air conditioned transit case having a protective, secondary lid for covering and protecting the thermoelectric air conditioner during transit; 
         FIGS. 12A and 12B  are an exploded perspective view of another exemplary embodiment of a thermoelectric air conditioned transit case having an extender piece for mounting the thermoelectric air conditioner to the transit case; 
         FIGS. 13A and 13B  is an exploded perspective view of another exemplary embodiment of a thermoelectric air conditioned transit case having two cases mounted to one another one, with the thermoelectric air conditioner mounted in a secondary case and the equipment to be protected in the primary case; 
         FIG. 14  is a chart illustrating exemplary design or performance standards for an exemplary transit case; 
         FIG. 15  is a perspective view of an exemplary thermoelectric air conditioner in accordance with the present invention; 
         FIG. 16  is a cross sectional view of the thermoelectric air conditioner of  FIG. 15 ; 
         FIG. 17  is an exploded perspective view of the thermoelectric air conditioner of  FIG. 15 ; 
         FIG. 18  is an exploded perspective view of an exemplary heat exchanger in accordance with the present invention; 
         FIG. 19  shows an exemplary heat sink with slotted fins for use with the thermoelectric air conditioner; 
         FIG. 20   a  shows an exemplary “cold side” cover of the thermoelectric air conditioner having a built-in condensate drip pan and  FIG. 20   b  shows another exemplary condensate drip pan; and 
         FIGS. 21A-21F  show features of another exemplary thermoelectrically air conditioned transit case. 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     The present invention is directed to systems and methods for maintaining a desired temperature within a portable case  2 , such as a transit case, using a thermoelectric heat exchanger  7 . In a preferred embodiment, one or more thermoelectric air conditioners  7  is mounted on or in a transit case  2  for cooling the contents (typically sensitive equipment and/or systems) within the transit case  2 . A properly sized thermoelectric air conditioner  7  is capable of reducing the temperature inside the case  2  below the ambient temperature outside the case  2 , thus providing a temperature inside the case  2  that is within the customer&#39;s goals and ensuring safe storage and/or operation of equipment. 
     At the same time, a thermoelectrically air conditioned transit case  1  preferably maintains most, if not all, of the benefits of using a transit case  2  (i.e., light-weight, mobile, stackable, durable, protective, etc.) to transport equipment from one location to another location. Also, a thermoelectric air conditioner  7 , as a solid-state device to control temperature, provides other benefits, including: highly reliable; virtually maintenance-free; no air exchange between outside and inside; suitable for use in operating environment up to about 140.degree. F.; indoor or outdoor use; vertical or horizontal installation; compact; light-weight; wide capacity range (e.g., about 200-2500 BTU range); cooling and/or heating models; no filters to change or clean; no compressor; no condenser; no refrigerants; no chemicals; no copper tubing; no moving components (other than fans); ideal for cooling electronics; no performance loss when input voltage drops or there are “brown-outs”; units are manufactured to UL standards; thermoelectric coolers can be conveniently powered from AC and/or DC power sources; and the like. 
     The thermoelectrically air conditioned transit case  1  includes several exemplary embodiments.  FIGS. 1-6  show exemplary internal embodiments of thermoelectrically air conditioned transit cases  1  having the thermoelectric air conditioner  7  located internally within the transit case  2 . In the exemplary internal embodiments shown in  FIGS. 1-6 , the thermoelectric air conditioner  7  is preferably mounted completely within an outer boundary (walls, covers, lids, etc.) of the case  2  and is completely protected by the transit case  2 . 
     In exemplary external embodiments shown in  FIGS. 7-10 , a thermoelectric air conditioner  7  is located externally on the transit case  2 .  FIG. 7A  shows an externally mounted thermoelectric air conditioner  7  wherein the thermoelectric air conditioner  7  is through-mounted on the transit case  2 . In the through-mounted embodiment, the thermoelectric air conditioner is located partially internal and partially external to the transit case  2  (i.e., partially inside and partially outside the outer boundary of the transit case). 
     In the exemplary external embodiment shown in  FIG. 7B , the externally mounted thermoelectric air conditioner  7  is flush-mounted outside the outer boundary (walls, covers, lids, etc.) and does not penetrate into the interior cavity  14  of the case  2 . An extension frame  37  is used to flush-mount the thermoelectric air conditioner  7  to the case  2  and the extension frame  37  extends between the mounting flange  73  of the thermoelectric air conditioner&#39;s mounting frame  72  and the exterior surface of the case  2  around the periphery of the opening  15  in the case  2 . This embodiment can be used where there is little or no room unoccupied by the equipment  5  within the internal cavity  14 . The cold side  76  of the thermoelectric air conditioner  7  is in thermal communication with the internal cavity  14  of the transit case  2  through an opening and/or passageway  15  in the wall  10  of the case  2 . The external, flush-mounted thermoelectric air conditioner  7  can be protected by a separate lid or cover  25  (see, for example,  FIG. 11 ). 
       FIG. 8  shows another embodiment of a transit case  2  having end covers  20  and the thermoelectric air conditioner  7  is externally mounted to the top of the case  2 . This embodiment may include a through-mounted and/or a flush-mounted thermoelectric air conditioner  7  and allows for easy access to the internal cavity  14  and the equipment  5  stored therein from one or either end of the case  2 . Preferably, the external, top mounted thermoelectric air conditioner  7  is removable or protected by a separate lid or cover  25  during transit. 
     The embodiment of  FIGS. 9A and 9B  show an externally mounted thermoelectric air conditioner  7  that is removably-mounted to the case  2 . As shown, the thermoelectric air conditioner  7  can be removably-mounted directly to the case  2 , to a cover or lid  20  of the case  2 . Alternatively, the thermoelectric air conditioner  7  can be removably-mounted to a separate, secondary cover or lid  24  (see  FIG. 10C ). As shown in  FIG. 9A , the thermoelectric air conditioner  7  is installed in or on the transit case  2  to control the temperature of the internal cavity  14  of the case  2  during operation. During transit, the thermoelectric air conditioner  7  can be removed and stored within the transit case  2 , as shown in  FIG. 9B . 
     In another embodiment shown in  FIGS. 10A-10D , the removable thermoelectric air conditioner  7  can be pre-mounted to a separate, secondary cover/lid  24  that can be stored in a separate, secondary case  2   b  during transit, and placed on the primary case  2   a  to be cooled after transit.  FIG. 10A  shows the primary case  2   a  (i.e., the case housing the equipment  5  to be cooled) ready for transit.  FIG. 10B  shows the secondary case  2   b  (i.e., the case housing the thermoelectric air conditioner  7  mounted to a secondary cover  24 ) ready for transit.  FIG. 10C  shows the secondary case  2   b  with its cover  20   b  open and the thermoelectric air conditioner  7  mounted to secondary cover  24  being removed. Although not shown, it is also contemplated that a complete case  2   a  (including the entire housing  3   a , cover  20   a , and mounted thermoelectric air conditioner  7 ) could be stowed within another, larger case  2   b  for transit.  FIG. 10D  shows the primary case  2   a  on-site, its transit cover  20   a  removed and the combination thermoelectric air conditioner  7  and secondary cover  24  installed/mounted to the lower portion of the primary case  2   a . The thermoelectrically air conditioned transit case  1  can now be placed in operation. The pre-mounting of the thermoelectric air conditioner  7  to a secondary cover  24  that is the same as the cover  20   a  used during transit of the primary case  2   a  allows for easy change-over from the transit mode to the operational mode because the secondary cover  24  preferably has the same dimensions, mating surface  46 , and closure system  95  as the cover  20   a  used during transit. 
     The externally mounted thermoelectric air conditioner  7  embodiments may also include a separate cover/lid  25  to cover the exposed portion of the thermoelectric air conditioner  7 . For example, in the exemplary through-mounted embodiment shown in  FIG. 11 , the cold side  76  of the thermoelectric air conditioner  7  extends through an opening  15  in the case wall  10  and hence is located and protected within the outer boundary of the transit case  2 . The hot side  77  of the thermoelectric air conditioner  7  is outside the outer boundary. The hot side  77  of the thermoelectric air conditioner  7  in this embodiment may be protected by a separate, secondary cover/lid  25 . A secondary cover/lid  25  may also be used with an external, flush-mounted embodiment. 
     The embodiment of  FIGS. 12A and 12B  includes a thermoelectric air conditioner  7  mounted to a transit case  2   a  using an extender piece  37  (i.e., an adapter/spacer/extension section). This transit case extender piece  37  is designed to attach to the primary transit case  2   a  in place of one of the primary transit case  2   a  covers/lids  20   a  and provide temperature control within the internal cavity  14   a  of the primary case  2   a , in which the equipment  5  is housed. 
       FIG. 12A  shows a thermoelectric air conditioner  7  mounted in a transit case extender piece  37  that is mounted vertically to the end of the primary transit case  2 . Preferably, a sealing gasket  81  is disposed between the mounting flange  73  of the thermoelectric air conditioner  7  and the mounting flange  38  of the extender piece  37 . Preferably, the existing closure system  95  (as shown latches  96 ) of the primary case  2   a  are used to engage corresponding closure mechanism  95  on the extender piece  37  to hold the extender piece  37  to the primary case  2   a.    
     As shown in  FIG. 12B , separate covers  25  may be attached to the ends of the transit case extender piece  37  to protect the thermoelectric air conditioner  7  during transport or storage. Alternatively, the transit case extender  37  can be left attached to the primary case  2   a  with a cover  25  added to protect the thermoelectric air conditioner  7  during transport and storage. 
     Alternatively, the thermoelectric air conditioner  7  and extender piece  37  can be mounted horizontally to the top of the primary transit case  2   a  (similar to the embodiment shown in  FIGS. 13A and 13B ). A separate cover  25  may then be attached to the top of the transit case extender piece  37  to protect the thermoelectric air conditioner  7  during transport or storage. 
     In another embodiment shown in  FIG. 13A , the thermoelectric air conditioner  7  may be located in a separate, secondary case  2   b  during transit that can be connected to the case  2   a  housing the equipment  5  to be protected during operation. Preferably, a sealing gasket  81  is disposed between the mounting flange  73  of the thermoelectric air conditioner  7  and the mounting flange  68  of the secondary case  2   b . Preferably, the existing closure system  95  (as shown latches  96 ) of the primary case  2   a  are used to engage a corresponding closure mechanism  95  on the secondary case  2   b  to hold the secondary case  2   b  to the primary case  2   a.    
     The secondary case  2   b  housing the thermoelectric air conditioner  7  may be connected—one on top of the other (as shown in  FIG. 13A ) or end-to-end (similar to the extender piece embodiment shown in FIG.  12 A)—to the primary case  2   a  housing the equipment  5  and then placed in-service to control the temperature of the internal cavity  14   a  of the primary case  2   a  to protect the equipment  5  housed therein. In use, the cold side  76  of the thermoelectric air conditioner  7  in the secondary case  2   b  is in thermal communication with the internal cavity  14   a  of the primary case  2   a . As shown in  FIG. 13B , removable covers  25  may be attached to the corresponding mating ends of the primary  2   a  and secondary transit cases  2   b  to protect the thermoelectric air conditioner  7  during transport or storage. 
     In addition, the thermoelectric air conditioner  7  can be mounted in either a vertical or horizontal orientation. For example, in the illustrated embodiments of  FIGS. 1-4 ,  12 A, and  12 B, the thermoelectric air conditioner  7  is mounted vertically proximate an opening  15  at one end/side of the case  2 . In the embodiments of  FIGS. 5-11 ,  13 A, and  13 B, the thermoelectric air conditioner  7  is mounted horizontally proximate an opening  15  in the top of the case  2 . 
     It is also contemplated that more than one thermoelectric air conditioner  7  can be mounted in or on a transit case  2 . For example, for a transit case  2  having front and rear covers  20 , such as  FIGS. 1-4  and  21 A- 21 F, one thermoelectric air conditioner  7  could be mounted in or on the front opening  15  and a second thermoelectric air conditioner  7  could be mounted in or on the rear opening  15 . Further, one thermoelectric air conditioner  7  could be top mounted while a second-thermoelectric air conditioner  7  could be end mounted. 
     The thermoelectrically air conditioned transit case  1  houses and protects sensitive equipment  5  contained within the case  2  during transit (i.e., shipment from one location to another location) and during use of the equipment  5  at remote locations. The thermoelectrically air conditioned transit case  1  includes a durable case  2  or housing coupled with a thermoelectric air conditioner  7  and is designed to protect sensitive equipment  5  stored therein from environmental conditions, including for example extreme temperature. Preferably, the thermoelectrically air conditioned transit case  1  is also constructed to be contaminant-tight (e.g., airtight, watertight, and dustproof) and to protect the equipment  5  from other environmental conditions including impact, shock, vibration, vandalism, and contaminants—such as air, water, moisture, humidity, dirt, dust, debris, chemicals, etc. The thermoelectric air conditioner  7  is capable of driving the temperature inside the transit case to a temperature below ambient. 
     The thermoelectrically air conditioned transit case  1  is designed to protect sensitive equipment and/or systems from the rigors of: commercial and industrial use; air, land, and sea shipment; temporary storage; worldwide military deployment; movements between remote locations; use at remote locations; and the like. Preferably the thermoelectrically air conditioned transit case  1  also enhances handling and the overall portability of the application, as explained more fully below. 
     Transit cases are known by various names. As used herein, the term transit case includes portable cases used to house, store, ship, transport, and protect equipment and/or systems in transits from one location to another location or as the equipment/system is used at a remote location. The thermoelectrically air conditioned transit case  1  is designed and constructed to protect temperature sensitive equipment and/or systems. Temperature sensitive equipment and/or systems include, for example, electrical, electronics, computer, server, weapons, mobile command and control, deployed air traffic control, surveillance, global positioning, instrumentation, communication, and the like. 
     Transit cases are manufactured by various manufacturers and come in a variety of styles, sizes, and shapes. In addition, the thermoelectric air conditioner  7  also comes in a variety of capacities to handle different loads and sizes of transit cases. The present invention contemplates the refabrication/retrofitting of existing transit cases  2  to include a thermoelectric air conditioner  7 , as well as implementation and installation of the thermoelectric air conditioner  7  during, or as part of, the original manufacturing of the transit case  2 . 
     The thermoelectrically air conditioned transit case  1  includes a portable protective housing  3  that is preferably light-weight, simple to design, rugged in construction, and economical to manufacture. Preferred material characteristics of the case include: high performance, impact-resistant, corrosion-resistant, UV-resistant, temperature-resistant, water-resistant, strong, durable, and the like. Suitable case materials include: Thermo Stamped Composite or TSC, which is glass-reinforced polyethylene, Rotomolded PE (polyethylene), injection molded ABS, Fiberglass (FRP), polyethylene for high impact strength, high impact structural copolymer, plastic, aluminum, plywood, canvas, nylon, leather, denim, polyester, light-weight metals, and other materials. Exemplary manufacturing techniques include rotational mold, injection mold, roto-mold, blow-mold, thermoformed processes, welded aluminum, drawn aluminum, and the like. 
     The case  2  of the thermoelectrically air conditioned transit case  1  can be manufactured as a standard case having standard dimensions and/or as a custom case that is manufactured to specific customer needs. For example, the case  2  can be manufactured to fit a particular payload and/or suite of equipment for a particular application, such as commercial, government, military, Homeland Security, etc. 
     Further, many military and defense customers require that cases meet certain design, environmental, and/or performance standards, such as MIL-STD-810 (shock, transit drop, vibration, water-tight, etc.); MIL-STD-1472 (lift limitations, see FIG. 14); MIL C-4150J; ATA (Air Transportation Association); loose cargo bounce; high/low temperature range; relative humidity; altitude, ultraviolet (UV) radiation; fungus; static loading; and the like. Preferably the design and construction of the thermoelectrically air conditioned transit case  1  take these design parameters and limitations into consideration. 
     Preferably, the thermoelectrically air conditioned transit case  1  is contaminant-tight (e.g., water-tight, air-tight, dust proof, etc.) when the cover  20  (and/or cover  25 ) is closed. Also, the interface between the thermoelectric air conditioner  7  and the transit case  2  is preferably contaminant-tight when the cover  20  of the transit case  2  is open. In addition, the interface between the hot side  77  and the cold side  76  of the thermoelectric air conditioner  7  is also preferably contaminant-tight. 
     The thermoelectrically air conditioned transit case  1  preferably includes a case closure system to close and seal any openings in the case  2 . For example, the case  2  closure system can include one or more covers and/or lids  20 ,  25 . Covers/lids  20 ,  25  are used to close openings  15  in the case  2  used to, for example, allow access to the internal cavity  14  of the case  2  to load or access equipment  5 . The covers/lids  20 ,  25  may be removably or pivotally mounted to the case  2 . In embodiments having covers/lids  20 ,  25  pivotally mounted to the case, the covers/lids  20 ,  25  may be attached using one or more hinges  27 . 
     In addition, the closure system preferably includes a closure mechanism  95 , such as one or more latches  96 . Case closures  95  are preferably heavy-duty, secure, strong, and easy to operate. Types of suitable case closures  95  include twist latches, “press and pull” latches, etc. In an exemplary embodiment, the latch  96  imposes an impact compressive force to seal cover/lid  20 ,  25  to the enclosure opening  15  when the latch  96  is closed. Preferably the latches  96  are located in a cavity or recess  97  formed in the body of the case  2  so the latches  96  are not in the way during handling or shipping of the case  2 . 
     Further, the case closure system can include a sealing system between the cover/lid  20 ,  25  and the case opening  15 . For example, the sealing system can include a tongue  84  and groove  85  located around the perimeter of an opening  15  to seal the cover/lid  20 ,  25  over the opening  15  when the case  2  closure is activated. The tongue  84  and corresponding groove  85  are preferably located having one structure on the case  2  and the corresponding structure on the cover/lid  20 ,  25 . In addition, a gasket  81  may be used to seal the connection of the cover/lid  20 , to the case opening  15 . 
     Moreover, the case closure system can include a lock (not shown) for securing the cover/lid  20 ,  25  over the opening  15  in the case  2 . The lock  98  may include any conventional locking mechanism and may be incorporated into the case  2  body or be a separate lock  98  that is independent from the case. The lock  98  helps deter tampering, theft, vandalism etc. 
     The portable thermoelectrically air conditioned transit case  1  preferably includes a case handling system. In one embodiment, the case handling system includes one or more handles  91 . Exemplary handles  91  include molded-in and/or hinged designs and the handles  91  may be sized and padded for comfort and ease of handling. 
     In another embodiment, the thermoelectrically air conditioned transit case  1  can include wheels or casters  100  to further assist in the portability of the case. The case can also include a cargo handling system, such as slots  101  formed in the bottom of the case to accommodate the forks of a fork-lift machine, eye-bolts (not shown) on top of the case to accommodate a crane, and the like. 
     The case closure system and handling system are preferably located at convenient locations on the housing and do not interfere with the operation, storage, or movement of the transit case. For example, preferably the latches  96 , handles  91 , etc. are located in grooves  92  or recesses  97  in the housing  2  and are positioned within the groove  92  or recess  97  when not in use and are accessible or capable of moving out of the groove  92  or recess  97  when in use. For example, the handles  91  can include swing-out handles. 
     In certain embodiments it may be desirable to store multiple thermoelectrically air conditioned transit cases  1  together either end to end or one on top of another. For those embodiments it is preferred that the thermoelectrically air conditioned transit cases  1  are stackable. The thermoelectrically air conditioned transit cases  1  may be stacked end-to-end and/or one on top of another. As shown in  FIG. 10A , the housing or body  3   a  of the case  2   a  may include a shoulder  103  and slot  104  design wherein the shoulder  103  of one case would be received within a corresponding slot  104  of an adjoining case  2   a . In addition, an interlock system (not shown) can be used wherein adjoining cases  2   a  could be locked together during, for example, transit, storage, and/or use. The interlocking system can include latches, ties, tie-downs, straps, belts, bands, and the like. 
     The thermoelectrically air conditioned transit case  1  can also include a mounting system for mounting the thermoelectric air conditioner  7  within the case. In one preferred embodiment, the mounting system includes a rack-mount frame  40 . 
     A rack-mount frame  40  is a supporting frame disposed within the housing  3  and spaced from the walls  10  and having an opening  42  on at least one side facing an opening  15  in the transit case  2  housing  3  for receiving the thermoelectric air conditioner  7 . As shown in  FIG. 4 , the thermoelectric air conditioner  7  includes a portion (i.e., the “cold side”  76 ) that can fit an opening  42  formed between the vertical rack rails  45  of the mounting frame  40  and the thermoelectric air conditioner  7  can be connected to the mounting frame  40  of the rack rails  45 . As shown in  FIG. 21C , the rack-mount frame  40  may also be used to hold other equipment, including the equipment  5  designed to be protected and cooled by the thermoelectric air conditioner  7 . 
     In the rack-mount  40  thermoelectric air conditioner  7  embodiment, the thermoelectric air conditioner  7  is mounted directly to the rack-mount frame  40  within the internal cavity  14  of the transit case  2 . The rack-mount frame  40  preferably includes standard mounting holes  41  and fasteners  43  for holding the thermoelectric air conditioner  7  and/or the equipment  5  in the rack  40 . For example, the rack-mount frame  40  can be designed in accordance with EIA-RETMA standards for portable electronics and include standard front mounting holes  41  and locking clip-nut fasteners  43  for holding the equipment  5  in the rack  40 . 
     The rack-mount frame  40  can include standard and custom rack-mounts. Standard rack-mounts include 19-inch, 23-inch, and 24-inch rack-mounts. Also, other standard sizes, as well as, custom rack-mount cases having varying dimensions can be used. In other embodiments, the rack-mount frame  40  can include multiple, different size racks, custom racks, and/or adjustable mounting frames. 
     In addition, a separate, adapter plate  82  can be used to fill-in or close the gap between the thermoelectric air conditioner  7  and the internal sides of the transit case  2 . The adapter plate  82  preferably includes a seal and/or gasket  81  that forms a boundary between the thermoelectric air conditioner  7  and the case  2 . This further enhances the ability of the transit case  2  to maintain, as close as possible, an airtight status and seal contaminants from the interior  14  of the case  2 . Further, the adapter plate  82  is preferably insulated to improve thermal efficiency. 
     The adapter plate  82  can extend around one or more sides of the thermoelectric air conditioner  7 . As shown in  FIG. 4 , the adapter plate  82  extends across and closes the gap between the top of the thermoelectric air conditioner  7  and an interior surface of the top of the case  2 . In a preferred embodiment, the adapter plate  82  is a solid piece to facilitate maintaining a contaminant-tight seal. Alternatively, the adapter plate  82  can include one or more sealed exit ports  83 , such as, for example, sealed cable exits, sealed control exits, and/or a sealed power receptacle. The adapter plate  82  can also include one or more controls  105  for controlling and monitoring an operation of the thermoelectric device. For example, a thermostat dial  105  can be provide on the adapter plate  82  for setting an output temperature of the thermoelectric device. 
     Further, in certain embodiments where the thermoelectric air conditioner  7  is installed on one end of the internal rack-mount frame  40 , a weight distribution problem might result. For example, consider an arrangement of mounting a thermoelectric air conditioner  7  in a transit case having a weight load of perhaps 60 lbs. on one end of the frame. If the end user were to install a minimal amount of electronics (i.e., 5 lbs.) on the other end of the rack  40 , this could result in an unbalanced load and the ruggedness and protection level of the case  2  could be compromised in such a scenario. However, the present invention solves this problem by providing for the installation of internal elastomer shocks  93  with different load ratings and/or additional shocks, thus balancing the load on the frame and taking into consideration the CG (center of gravity) of the load. 
     In other embodiments where impact sensitive equipment is stored within the case  2 , the thermoelectrically air conditioned transit case  1  can include a shock, vibration, and/or noise mitigating system. In these impact sensitive embodiments, the case is preferably shock, vibration, and/or noise absorbing (“shock absorbing”). For example, elastomer shock mounts  93  can be used between the thermoelectric air conditioner  7  and the case  2  to isolate the thermoelectric air conditioner  7  and absorb any shock or vibration. In a rack-mount  40  embodiment, shock mounts  93  can be located inside the case  2 , for example, between the frame of the rack-mount frame  40  and the housing  3  of the case  2 . This design provides protection to the thermoelectric air conditioner  7  and equipment  5  mounted to the frame of the rack-mount  40  housed within the case  2 . Also, if the thermoelectrically air conditioned transit case  1  is made from a plastic material, the plastic material itself can be shock absorbing and the case absorbs some of the shock. 
     In addition, a cushioning system can be provided to further hold and protect the thermoelectric air conditioner and equipment  5  located within the thermoelectrically air conditioned transit case  1 . For example, a customizable foam interior (not shown) can be used with the shape and amount of foam determined by the shape and the characteristics of the equipment  5  being protected. The cushioning system can be manufactured into the case or can be insertable. The cushioning system decelerates the equipment  5  in a controlled manner if the case is dropped or otherwise subjected to shock or vibration. 
     As shown in  FIGS. 5 ,  7 A,  7 B,  10 B, and  10 C, the thermoelectrically air conditioned transit case  1  preferably includes a pressure relief valve  86  that equalizes the pressure inside and outside the case  2 . In a more preferred embodiment, the pressure relief valve  86  is an automatic pressure relief valve that automatically equalizes the pressure. The pressure relief valve  86  provides a watertight and airtight seal during transit, such as air travel where the thermoelectrically air conditioned transit case  1  experiences varying elevations, and thus pressures. 
       FIGS. 15-18  show an exemplary thermoelectric heat exchanger. The thermoelectric heat exchanger in this case, a thermoelectric air conditioner  7  for cooling the inside or internal cavity  14  of the case  2 , includes one or more thermocouples and at least one heat sink  126 ,  128 . The thermocouples are made from semiconductors and the semiconductor is heavily doped to create an excess (n-type) and a deficiency (p-type) of electrons. The junction between the n-type and the p-type is a semiconductor thermocouple. At the cold side  76 , energy (heat) is absorbed by electrons as they pass from a low energy level in the p-type semiconductor element, to a higher energy level in the n-type semiconductor element. The power supply provides the energy to move the electrons through the system. At the hot side  77 , energy is expelled to a heat sink  128  as electrons move from a high energy level element (n-type) to a lower energy level element (p-type). Heat absorbed at the cold side  76  is pumped to the hot side  77  at a rate proportional to current passing through the circuit and the number of couples. 
     These thermocouples, which can be connected in series electrically and in parallel thermally, are integrated into the thermoelectric air conditioner  7 . The thermoelectric modules  141  are packaged between metallized ceramic plates. Thermoelectric modules  141  can be mounted in parallel to increase the heat transfer effect or can be stacked in multistage cascades to achieve high differential temperatures. Solid state cooling is relatively simple compared to some of the classical techniques, such as using a compressor, because there are no moving parts (other than fans). 
     These thermoelectric devices have the capability to be either heating systems or cooling systems depending on the direction of the current. In addition, the thermoelectric devices can include embedded resistive heaters within the cold side in order to effect heating within the internal cavity  14 . The following description focuses on a thermoelectric heat exchanger that is used for cooling, i.e., a thermoelectric air conditioner  7 . In the cooling embodiment shown and described, the thermoelectric air conditioner  7  is designed to exhaust heat from inside the transit case  2  to outside the transit case  2  to protect thermally sensitive equipment  5  in the transit case  2 . 
     Unlike a conventional air conditioner, the thermoelectric air conditioner  7  used to cool equipment  5  within the transit case  2  is a solid state device and has no compressor, refrigerants or filters, and provides reliable, maintenance-free cooling of the interior (i.e., internal cavity) of the transit case  2 . 
     Preferably the thermoelectrically air conditioned transit case  1  is designed and constructed to increase contaminant resistance (i.e., minimizing the transfer of contaminants from the hot side—or outside of the transit case  2 —to the cold side—or inside of the transit case  2 ) and to improve thermal efficiency (i.e., minimize the transfer of thermal energy from the hot side—or outside—to the cold side—or inside—by increasing thermal isolation between the hot side and the cold side). 
     For example, the thermoelectric air conditioner  7  is preferably sealed to be contaminant-resistant and to minimize heat transfer between the hot side  77  and the cold side  76 . Also, the connection between the thermoelectric air conditioner  7  and the transit case  2  is also preferably designed to be contaminant-resistant and to improve thermal efficiency. In addition, that transit case housing  3  and cover(s)  20 ,  25  are preferably designed to be contaminant-resistant and thermally efficient. 
     Contaminant-resistant means zero or substantially zero contaminants will pass between the hot side  77  and the cold side  76  of the thermoelectric air conditioner  7  and/or from the outside to the inside of the transit case  2 . By making the thermoelectrically air conditioned transit case  1  contaminant-resistant, the long term reliability and performance of the equipment  5  stored in the transit case  2  may be improved by minimizing any damage from outside contaminants. 
     Thermal efficiency means reducing/minimizing thermal heat transfer from the hot side  77  to the cold side  76  of the thermoelectric air conditioner  7  and/or from outside the transit case  2  to inside the transit case  2 . Thermal efficiency can be increased by, for example, using a reflective material on the outside of the case  2 , using a UV resistant material for the case  2 , using an insulating material around the inside of the case  2 , using an insulating material at the connection between the thermoelectric air conditioner  7  and the case  2 , and the like. Thermal efficiency can also be increased by designing the system with heat producing electrical components being mounted on a power pack heat sink  127 , which exhausts heat to the hot side  77  of the thermoelectric air conditioner  7 . Therefore, the heat generated from the heat producing components is dissipated directly to the hot side  77  of the thermoelectric air conditioner  7 . 
       FIGS. 15-18  show various features of an exemplary thermoelectric air conditioner  7 . As shown, in  FIG. 15 , the thermoelectric air conditioner  7  includes a housing having a cold side cover  110  that covers the components on a cold side  76  of the thermoelectric air conditioner  7 , a hot side cover  111  that covers the components on a hot side  77  of the thermoelectric air conditioner  7 , and a mounting frame  72  positioned between cold side cover  110  and hot side cover  111 . 
     As shown, mounting frame  72  includes a mounting flange  73  formed over the outer periphery of at least two sides of mounting frame  72  and that extend outside of the housing. A plurality of through holes  74  are formed in mounting flange  73  for mounting the thermoelectric air conditioner  7  directly to the transit case  2  or to a mounting frame  40  within the transit case  2 . In the embodiment shown, the mounting frame  72  also includes a plurality of through holes  113 , corresponding to through holes  118 ,  135  in the cold side cover  110  and the hot side cover  111  for mounting both cold side cover  110  and hot side cover  111  to mounting frame  72 . 
     Cold side cover  110  includes a substantially planar body  114  having side walls  115  that define a cold side cavity  116 . Opening  117  allows air to access the cold side cavity  116 . 
     As shown, a cold side fan  123  is mounted to cold side cover  110  proximate to fan opening  122 . Cold side fan  123  forces air through the fan opening  122 , across the cold side  76  of the thermoelectric air conditioner  7 , and out of the opening  117 . 
     In a typical mounting to a transit case  2 , cold side cover  110  extends into or is in thermal communication with the internal space  14  of the transit case  2  and hot side cover  111  extends outside of or is in thermal communication with the outside of the transit case  2 . 
     As shown in  FIG. 15 , the thermoelectric air conditioner  7  includes one or more controls, including a thermostat control knob  119  to allow an operator to adjust the temperature set-point of the thermoelectric air conditioner  7 , a circuit breaker  120  to trip the device on, for example, an over-current condition, a power cord  121  for supply power to the device, and the like. 
       FIG. 16  is a cross sectional view of an exemplary thermoelectric air conditioner  7  showing a barrier  112  between the cold side  76  and the hot side  77 . Power pack heat sink  127  includes a base portion  163  having with a plurality of fins  164  extending from one side of the base portion  163 . Power pack heat sink  127  is mounted, proximate to power pack cutout  125 , on the hot side  77  of mounting frame  72 , with the base portion  163  proximate to the mounting frame  72 . Gasket  165  is attached to the cold side  76  of the mounting frame  72  proximate to the power pack cutout  125 . Preferably, power pack cover  158  is secured to gasket  165  with cover seal  167  proximate to the gasket  165 . Electrical components  159 ,  160 ,  161 , and  162  ( 159  and  161  not shown) are mounted to the base portion  163  of the power pack heat sink  127  and protrude through power pack cutout  125  in mounting frame  72  into a cavity  166 . Mounting frame  72 , gasket  165 , and power pack cover  158  define a non-planar barrier  112  between a cold side  76  and a hot side  77 . 
       FIG. 17  shows the interior of the housing of  FIG. 15 . As shown in  FIG. 17 , the housing includes mounting frame  72 , cold side cover  110 , and hot side cover  111 . In the embodiment shown, the mounting frame  72  includes two heat sink cutouts  124  and one power pack cutout  125 . Mounting frame  72  is located between the cold side  76  and the hot side  77 . The cold side  76  includes cold side heat sinks  126 . Cold side heat sinks  126  are attached on the cold side  76  of mounting frame  72 . The hot side  77  includes power pack heat sink  127  and at least one hot side heat sinks  128 . Hot side heat sinks  128  are attached on the hot side of mounting frame  72 . Power pack heat sink  127  is attached on the hot side of mounting frame  72 . 
     Power supply assembly  129  may include power pack heat sink  127 , and a plurality of electrical components including, for example, a DC to DC active power supply  159 , one or more filter capacitors  160 , a bridge rectifier  161 , and a noise suppression filter  162 , and associated circuitry (not shown). 
     Hot side cover  111  includes a substantially planar body  130  having side walls  131  that define a hot side cavity  132 . Opening  133  allows air to access the hot side cavity  132 . Hot side cover  111  includes mounting brackets  134  that extend outward from side walls  131 . The mounting brackets  134  includes a plurality of through holes  135  for receiving fasteners (not shown) for mounting the hot side cover  111  to the mounting frame  72 . Mounting frame  72  includes through holes  113  corresponding to through holes  135  of hot side cover  111 . Fasteners (not shown) pass through holes  113  and through holes  135  to secure hot side cover  111  to mounting frame  72 . 
     The hot side includes one or more hot side fans  137  mounted proximate fan openings  136  in hot side cover  111 . The hot side fans  137  draw air across the power pack heat sink  127  to remove heat and also force air through the fan openings  136 , across the hot side  77  of the thermoelectric air conditioner  7 , and out of the opening  133 . Hot side heat sinks  128 , (which are shown in  FIG. 18 ) are mounted to the hot side  77  of mounting frame  72 . Hot side fans  137  also draw air across hot side heat sinks  128  to expel heat to the outside of the thermoelectric air conditioner  7 . 
     A wire feed opening  140  is located in mounting frame  72  and provides access for running wires (not shown) between the hot side  77  and cold side  76 . Wires are disposed through the wire feed opening  140  and sealed completely by a liquid tight compression fitting  139  disposed in wire feed opening  140 . The liquid tight compression fitting  139  may increase thermal efficiency by preventing moisture and heat from reaching the cold side  76 . The liquid tight compression fitting  139  may also increase the life of the thermoelectric air conditioner  7  by preventing moisture from reaching electrical components  159 ,  160 ,  161  and  162 , thereby, increasing the life of the electrical components. As shown in  FIG. 17 , the electrical components include a DC to DC active power supply  159 , filter capacitors  160 , a bridge rectifier  161 , and a noise suppression filter  162 , and associated circuitry (not shown). Sealant  138  may be disposed in wire feed opening  140  to further seal the wire feed opening  140 . 
       FIG. 18  is an exploded perspective view of an exemplary thermoelectric air conditioner  7 . As shown in  FIG. 18 , thermoelectric air conditioner  7  includes at least one thermoelectric module  141 , at least one hot side heat sink  128 , and at least one cold side heat sink  126 . Mounting frame  72  includes at least one heat sink cutout  124 . Heat sink cutout  124  allows the thermoelectric modules  141  to contact both the hot side heat sink  128  and the cold side heat sink  126 . The contact between hot side heat sink  128  and cold side heat sink  126  provides for heat transfer between the cold side  76  and the hot side  77  allowing the internal cavity of the transit case to be cooled. 
     As shown, hot side heat sink  128  includes a base portion  142  and a plurality of fins  143  extending in a substantially orthogonal direction from the base portion  142 . The plurality of fins  143  provides more surface area for better heat transfer. 
     Hot side heat sink  128  is preferably attached to the hot side  77  of mounting frame  72 , proximate to heat sink cutout  124  through blind holes  144  and fasteners  146 . The blind holes  144  provide for attachment to the mounting frame  72  without providing a path for air and moisture. This provides a moisture resistant barrier between the hot side  77  and the cold side  76 , increasing thermal isolation and minimizing the risk of moisture reaching the thermoelectric modules  141  or electrical components  159 ,  160 ,  161  and  162  (not shown). The use of blind holes  144  also maximizes thermal isolation creating a moisture resistant barrier between the hot side  77  and the cold side  76 . 
     In a preferred embodiment, a sealant is placed around the perimeter of the base, between the hot side heat sink  128  and the mounting frame  72  to further seal any gaps, providing moisture resistance and thermal isolation. This moisture resistance feature functions to increase the long-term reliability of the thermoelectric air conditioner  7 . 
     Preferably, hot side heat sink  128  also includes a plurality of blind holes  145  located along a centerline  147  of the base, opposite the plurality of fins  143 . Blind holes  145  are provided to attach the cold side heat sink  126  to the thermoelectric air conditioner  7  using fasteners  146 . The blind holes  145  provide for attachment to the mounting frame  72  without providing a path for air and moisture. This minimizes the risk of moisture passing between the hot side  77  and the cold side  76 , increasing thermal isolation and minimizing the risk of moisture reaching the thermoelectric modules  141  or electrical components  159 ,  160 ,  161  and  162  (not shown). The use of blind holes  145  also maximizes thermal isolation by not allowing air or moisture to flow between the hot side  77  and the cold side  76 . 
     The thermoelectric air conditioner may also include a sealing frame  151  adapted to allow one or more thermoelectric modules  141  to be disposed therein and to contact the hot side heat sink  128  and the cold side heat sink  126 . As shown, sealing frame  151  is attached to the cold side  76  of the mounting frame  72 , proximate to heat sink cutout  124 , with fasteners (not shown) secured into the blind holes  144  of the hot side heat sink  128 . The sealing frame  151  provides the ability to seal against the mounting frame  72 , to secure insulation  153  in place, and to seal between the sealing frame  151  and the cold side heat sinks  126 . A sealant  138  is preferably placed between the sealing frame  151  and the mounting frame  72  and between the sealing frame  151  and the cold side heat sink  126 . 
     Thermoelectric modules  141  have a relatively flat and planar body and, as shown in  FIG. 18 , have a substantially rectangular shape. At least two wires  154  are attached to the thermoelectric modules  141 . Wires  154  provide a means for applying power to the thermoelectric modules  141 . At least one thermoelectric modules  141  are affixed to each hot side heat sink  128 , substantially coplanar with the mounting frame  72 . Preferably, the thermoelectric modules  141  are substantially centered within each quadrant of sealing frame  151 . 
     Conductive material  155  is disposed on both the hot side  77  and the cold side  76  of the thermoelectric modules  141  to promote good thermal coupling. Preferably, the conductive material  155  is a thermal grease. 
     In a preferred embodiment, one or more thermally conductive spacer blocks  156  are placed on the cold side  76  of thermoelectric modules  141 . Conductive material  155  is disposed between the thermoelectric modules  141  and the thermally conductive spacer blocks  156  to increase thermal conductivity. Thermally conductive spacer blocks  156  increase the separation distance between the hot side heat sink  128  and the cold side heat sink  126 , reducing thermal losses which may occur from any thermal short circuiting between the hot side heat sink  128  and the cold side heat sink  126 . 
     Cold side heat sink  126  includes a substantially rectangular base portion  148  and a plurality of fins  149  extending in a substantially orthogonal direction from the base portion  148 . The plurality of fins  149  provide more surface area for better heat transfer. 
     As shown, cold side heat sink  126  is mounted with base portion  148  proximate to on the thermally conductive spacer blocks  156  on the cold side  76  of mounting frame  72  and with base portion  148  proximate the sealing frame  151 . Cold side heat sinks  126  contact the thermally conductive spacer blocks  156 . Preferably, conductive material  155  is applied between the thermally conductive spacer blocks  156  and the cold side heat sink  126  to promote thermal transfer. Preferably, cold side sink  126  also includes a plurality of through holes  150  corresponding to blind holes  145  in hot side heat sink  128 . Through holes  150  are provided to attach the cold side heat sink  126  to the blind holes  145  of hot side heat sink  128  using fasteners  146 . Preferably, the fasteners  146  include sealing washers. This minimizes the risk of moisture passing between the hot side  77  and the cold side  76 , increasing thermal isolation and minimizing the risk of moisture reaching the thermoelectric modules  141  or electrical components  159 ,  160 ,  161  and  162  (not shown). 
     As shown, insulation  153 —having thermally insulating properties—is disposed between the sealing frame  151  and the cold side heat sink  126  to secure the thermally conductive spacer blocks  156  and to provide increased thermal isolation between the hot side heat sink  128  and cold side heat sink  126 . Thermoelectric module wires  154  run from the thermoelectric modules  141 , are secured with wiring constraints  157  and run through wire holes  152  located in sealing frame  151 . Wire holes  152  are completely sealed with sealant  138  to increase thermal efficiency and to prevent moisture from reaching the thermoelectric modules  141 . 
     The sealant  138  at various locations in the thermoelectric air conditioner helps form a moisture resistant barrier that resists the introduction of moisture during operation of the thermoelectric air conditioner  7 . For example, humid moisture-laden air is drawn through the cold side heat sink  126 . Once cooled, the air which may have humidity levels approaching 100% can no longer contain as much moisture as it cools, and the air borne moisture then condenses onto the various cooling system components. Unless moisture is prevented from entering the thermoelectric air conditioner  7  by thoroughly sealing the thermoelectric modules  141  this moisture may ultimately saturate various locations causing damage to the thermoelectric modules  141  by, for example, chemical degradation, electrolysis, or the like. These sealing features also minimize moisture flow between the hot side  77  and the cold side  76 , which improves thermoelectric air conditioner  7  efficiency. 
     Additional details regarding the thermoelectric air conditioners can be found in U.S. Pat. No. 6,345,507, entitled COMPACT THERMOELECTRIC COOLING SYSTEM, issued on Feb. 12, 2002 and U.S. Pat. No. 6,499,306, COMPACT THERMOELECTRIC COOLING SYSTEM, issued on Dec. 31, 2002, the disclosures of all of which are herein incorporated by reference. 
     In addition, the thermoelectrically air conditioned transit case  1  may include a sealing system, such as a gasket  81 , for sealing the connection between the thermoelectric air conditioner  7  and the transit case  2 . Where the thermoelectric air conditioner  7  is mounted to an opening  15  in the transit case  2 , the gasket  81  can be disposed between the mounting flange  73  and the transit case  2  opening  15  and can be adapted to the size of the opening  15  and mounting flange  73 . Preferably, the gasket  81  is water and oil resistant neoprene. Fasteners  75 , such as sealing screws (not shown), are disposed in through holes  74  to secure the mounting flange  73  to the transit case  2  opening  15 . The use of a gasket  81  and sealing screws  75  provide moisture resistance between the cold side  76  and the hot side  77  (i.e., between the inside and the outside) when the thermoelectric air conditioner  7  is installed in or on the transit case  2 . 
     The thermoelectric air conditioned transit case can also include temperature selection means and temperature sensing means for setting and monitoring a temperature in said internal cavity  14 . For example, as shown in  FIG. 4  the temperature selection means can include a thermostat  105  for setting a desired temperature and the temperature sensing means can include a temperature probe  106  for monitoring the temperature in the internal cavity  14  of the transit case  2 . The temperature can be varied by controlling the current flow through the thermoelectric device  7 . 
     The thermoelectric air conditioner  7  includes a power source  159 . Preferably, the power source can include AC and/or DC power. For example, the thermoelectric air conditioner  7  can include a power cord  121  for plugging into a standard power receptacle. In one preferred embodiment, the power source  159  includes a DC to DC active power supply to minimize size and reduce waste heat. Preferably, the thermoelectric air conditioner  7  is designed with a programmable power control system to maximize cooling for a given design and operating conditions. 
     In addition, the thermoelectrically air conditioned transit case  1  can include a case power source. In this embodiment, the thermoelectric air conditioner  7  can be electrically connected (i.e., hard-wired or plugged into) to the case power supply. The transit case power supply can in turn include a plug and power cord that can be connected to an external power source (wall outlet, lighter adapter, aircraft adapter, etc.). Furthermore, the thermoelectrically air conditioned transit case  1  can include an Uninterruptible Power Supply (UPS). 
     With overall weight of the portable thermoelectrically air conditioned transit case  1  being a concern, it is preferred that the transit cases  2  and the thermoelectric air conditioners  7  have light-weight designs. Preferably, the cases  2  include light-weight designs that use, for example, Thermo Stamped Composite (TSC), which is glass-reinforced polypropylene, Rotomolded PE (polyethylene), injection molded ABS, Fiberglass (FRP), and/or light-weight metal (such as Aluminum) materials. It is also contemplated that other light-weight composites and hybrid materials can be used. Other suitable materials include wood, fabric, canvas, vinyl, etc. 
     Further, the weight of a thermoelectric air conditioner  7  can also be reduced by, for example, changing the materials of some of the components, such as changing some components to Aluminum, and also reducing the size of components. Also, the thermoelectric air conditioner  7  can include a compact design, a light-weight power supply design and lay-out to help keep the weight of the overall thermoelectrically air conditioned transit case  1  to a minimum. 
     Several exemplary embodiments are outlined below illustrating systems and methods for cooling the contents of a transit case and for mounting a thermoelectric air conditioner  7  to a transit case  2 . 
       FIGS. 1-4  show an exemplary internal thermoelectric air conditioner  7  embodiment. As shown, the case has front and rear covers  20  (although cases having a single cover are also contemplated) and a metal frame  40  inside the case internal cavity  14 . As shown, the frame includes a 19-inch rack-mount frame  40 . The covers  20  can also be called lids, doors, etc., and can be hinged or entirely removable. The thermoelectric air conditioner  7  mounts on the end of the frame  40 , concealed inside the case when in the transit mode, viewable when in the operational mode. As shown, shock mounts  93  are positioned between the frame  40  and the walls  10  of the case  2 . As shown, the thermoelectric air conditioner  7  is installed through the end opening  15  of the case  2 . The cold side  76  of the thermoelectric air conditioner  7  extends into an opening  42  in the frame  40  and the mounting flange  73  of the thermoelectric air conditioner  7  is connected to the frame  40 . A tongue  84  and groove  85  arrangement is shown for sealing the opening  15  when the cover  20  is secured over the end opening  15  of the case  2 . An adapter plate  82  is also shown for filling-in and sealing the space between the thermoelectric air conditioner  7  and the case walls  10 . In this embodiment, the air conditioner  7  is totally contained within the case  2  when the cover  20  is secured to the case  2  over the end opening  15 . In this configuration, not only can one not tell there is an air conditioner  7  incorporated into the case  2  when the case  2  is in the transit mode, but the air conditioner  7  is totally protected by the design of the case  2 , the mounting arrangement, the shock-mounted frame  40 , etc. 
       FIGS. 5 and 6  show another internal thermoelectric air conditioner  7  embodiment. In the illustrated embodiments, the case includes a top cover  20  and the thermoelectric air conditioner  7  mounts inside the case  2  on a mounting plate  30  that is secured to the opening  15  of the case  2 ′ As shown, the thermoelectric air conditioner  7  is concealed when in the transit mode and viewable when in the operational mode. In this embodiment, the top cover  20  is pivotally connected to the case  2  by hinges  27  and the thermoelectric air conditioner  7  is totally contained within the case  2  when the top cover  20  is closed. When the case  2  is in the transit mode, it is not apparent there is a thermoelectric air conditioner  7  incorporated into the case  2 , and the air conditioner  7  is totally protected by the design of the case  2 , the mounting arrangement, the shock-mounted frame  40 , etc. As shown in  FIG. 5 , the case  2  can include wheels  100  to assist in the portability of the transit case  2 . 
       FIGS. 7A-B  show cases  2  with a top cover  20  and  FIG. 8  shows a case  2  with an end cover  20 . In each figure, the thermoelectric air conditioner  7  mounts on the top or side or end of the case  2 . In the embodiments of  FIGS. 7A ,  7 B, and  8 , the thermoelectric air conditioner  7  is not concealed inside the case  2  when the case  2  is in the transit or operational mode.  FIG. 7A  shows a horizontal, through-mounted thermoelectric air conditioner  7  on top of the case  2 , wherein at least a portion of the cold side  76  of the thermoelectric air conditioner  7  extends into the internal cavity  14  of the case  2 .  FIG. 7B  shows a horizontal, flush-mounted thermoelectric air conditioner  7  on top of the case  2 , wherein no portion of the thermoelectric air conditioner  7  extends into the internal cavity  14  of the case  2 . Although not shown, the embodiments of  FIGS. 7A and 7B  can include a separate transit lid  25  for covering and protecting the thermoelectric air conditioner  7  during transit. The transit lid  25  can include a plastic, metal, and/or wire mesh configuration. 
       FIG. 8  shows a case having front and rear covers  20  where the thermoelectric air conditioner  7  mounts on the top of the case  2 .  FIG. 8  shows a horizontal, through-mounted thermoelectric air conditioner  7  on one side of the case  2 , wherein at least a portion of the thermoelectric air conditioner  7  extends into the internal cavity  14  of the case  2 . The thermoelectric air conditioner  7  is not concealed inside when the case  2  is in the transit or operational mode. Similar to the embodiments of  FIGS. 7A-7B , the thermoelectric air conditioner  7  of  FIG. 8  may be flush-mounted and/or through-mounted. Although not shown, the embodiment of  FIG. 8  can include a separate transit lid  25  for covering and protecting the thermoelectric air conditioner  7  during transit. Also, the thermoelectric air conditioner in any of the flush-mounted and/or through-mounted embodiments could be mounted vertically at one side or end of the case  2 . 
     Thermoelectric air conditioner  7  may also be removably mounted in or on the transit case  2  although this is more preferred for embodiments wherein the thermoelectric air conditioner  7  is externally mounted. In the embodiments of  FIGS. 9A and 9B , the thermoelectric air conditioner  7  is removably mounted to the mounting plate  30  of the transit case  2 . As shown in  FIG. 9A , the thermoelectric air conditioner  7  is not concealed inside the case  2  when the case  2  is in the operational mode. But during transit the thermoelectric air conditioner  7  can be removed and can be stowed within the transit case  2  and thus can be concealed inside the case  2  when the case  2  is in the transit mode, as shown in  FIG. 9B . 
     Alternatively, as shown in  FIGS. 1A-10D  the thermoelectric air conditioner can be shipped and protected in a separate case  2   b . Once on-site the thermoelectric air conditioner can be removed from its shipping case  2   b  (secondary case  2   b ) and connected to the transit case  2   a  housing the temperature sensitive equipment  5  (primary case  2   a ) and placed in operation. 
       FIG. 11  shows an alternate embodiment of the externally mounted thermoelectric air conditioner  7  further comprising a separate, secondary cover  25  for containing and protecting the thermoelectric air conditioner during transit. Once on-site, this secondary cover  25  can be removed exposing the thermoelectric air conditioner  7  for operation. This embodiment shows a case having a top cover  20  and the thermoelectric air conditioner  7  mounted on the top of the case  2 , but is also applicable for cases  2  having an end cover  20  and the thermoelectric air conditioner  7  mounted on the end of the case  2 . In this embodiment, the thermoelectric air conditioner  7  is concealed inside the secondary cover  25  when the case  2  is in the transit mode. 
       FIGS. 12A-12B  and  13 A- 13 B illustrate yet other embodiments wherein the thermoelectric air conditioner  7  is mounted in an extender piece  37  ( FIGS. 12A-12B ) and/or a secondary case  2   b  that is separate from the primary case  2   a  housing the equipment  5  to be protected ( FIGS. 13A-13B ). Preferably, the extender piece  37  and/or secondary case  2   b  include removable covers/lids/panels  25  on corresponding mating wall (e.g., top/bottom, end/end, side/side) as the mating wall of the primary case  2   a , which is includes a removable cover  20   a.    
     This allows, for example in the case of an embodiment having a secondary case, the two cases  2   a , 2   b  to be connected such that the thermoelectric air conditioner  7  in the secondary case  2   b  is in thermal communication with the internal cavity  14   a  of the primary case  2   a  in order to control the temperature of the internal cavity  14   a  of the primary case  2   a . The removable cover/lid/panel  20   b  on the secondary case  2   b  (i.e., the case housing the thermoelectric air conditioner  7 ) covers and protects the thermoelectric air conditioner  7  during transit. The removable cover/lid/panel  25  on the primary case  2   a  (i.e., the case housing the equipment  5 ) covers and protects the equipment  5  during transit. 
     During operation, the two removable covers/lids/panels  25  are removed and the primary and secondary cases  2   a ,  2   b  are connected to one another. The openings  15   a ,  15   b  in the cases  2   a ,  2   b  wherein the covers/lids/panels  25  were removed allows the thermoelectric air conditioner  7  to be in thermal communication with the internal cavity  14   a  of the primary case  2   a . Alternatively, as shown in  FIGS. 13A and 13B  air passageways can be formed between the cold side  76  of the thermoelectric air conditioner  7  in the secondary case  2   b  and the internal cavity  14   a  of the primary case  2   a  to help facilitate air flow between the thermoelectric air conditioner  7  and the internal cavity  14   a . Also, the primary  2   a  and secondary  2   b  cases can be connected end-to-end, as shown in  FIGS. 12A and 12B , and/or one on top of another, as shown in  FIGS. 13A and 13B . 
     In still another embodiment, a standard “vertical” mounting orientation of an exemplary thermoelectric air conditioner  7  provides for the long side of the mounting flange  73  on the thermoelectric air conditioner  7  to be in the vertical direction. In this type of arrangement, the thermoelectric air conditioner  7  can be rotated approximately 90 degrees so that it would match with the dimensional constraints of the transit case  2 . 
     This arrangement requires features that deal with condensate collection issues. Condensate collection can be addressed through the use of one or more of the following features: (1) slotted heat sink fins  107  which allow condensate to be drawn down by gravity (see  FIG. 19 ); (2) a modified “cold side” cover  110  which includes a built-in and/or separate condensate drip pan  108  at the bottom (see  FIGS. 20   a  and  20   b , respectively); (3) desiccant containers (not shown) that can be mounted within the transit case  2  to aid in absorbing moisture. The desiccant can include a feature to indicate when it is expired or used up. For example, the desiccant can change color when it requires renewal/replenishment. As shown in  FIG. 20   b , the condensate drip pan  108  can also include a hose  109  for leading any condensation away from the thermoelectric air conditioner  7 . 
       FIGS. 21A-21F  shows several views of one exemplary thermoelectrically air conditioned transit case  1 .  FIG. 21A  shows a transit case  2  with front and rear covers  20  in place. As shown, two (of four) handles  91  are visible. The front and rear covers  20  are secured to the case  2  housing by latches  96 . 
       FIG. 21B  is a front view showing the front cover  20  partially removed. Rack rails  45 , such as 19-inch rack rails, can be used for mounting both the equipment  5  as well as the thermoelectric air conditioner  7 . For example, a 19-inch oscilloscope is shown in  FIG. 21B . Shock mounts  93  are disposed between the case walls  10  and the rack rails  45 . Other equipment and/or an adapter plate (not shown) may be connected to the rack rails below the depicted oscilloscope to fill the front opening and seal the interior space. 
       FIG. 21C  shows the front cover  20  removed entirely. As shown, complete access to the front side of the equipment  5  is provided. As shown, a rack frame  40  has a 24-inch depth (rail to rail). Other frame sizes are also available having varying dimensions, such as, for example, between about 17 to about 30-inch depth. In this embodiment, the front cover  20  is on when the transit case  2  is being transported and can be removed and/or left in place when the thermoelectric air conditioner  7  is cooling the electronics within the case  2 . An adapter plate (not shown) can be mounted below and around the equipment  5  to seal the internal cavity  14  during operation when the cover  20  is removed. 
       FIG. 21D  is a rear view showing both covers  20  (rear and front) in place. As shown, the thermoelectric air conditioner  7  is completely concealed and contained within the case  2 . 
       FIG. 21E  shows the rear cover  20  partially removed. Preferably, the rear cover  20  is on when the transit case is being transported and off when the thermoelectric air conditioner  7  is cooling the electronics within the case  2 . The thermoelectric air conditioner  7  and adapter plate  82  seal the interior cavity  14  from the outside environment. 
       FIG. 21F  shows the rear cover  20  removed entirely. Rack rails  45 , such as the same 19-inch rack rails used to hold the equipment  5 , can be used to mount the thermoelectric air conditioner  7  in a special orientation, with special light-weight (e.g., Aluminum) components, a special (AC and/or DC) power arrangement, and a special light-weight adapter plate  82 /gasket  81  assembly to seal out contaminants. Power cables  121  can exit through a connector (not shown) positioned on the adapter plate  82 . 
     While systems and methods have been described and illustrated with reference to specific embodiments, those skilled in the art will recognize that modification and variations may be made without departing from the principles described above and set forth in the following claims. Accordingly, reference should be made to the following claims as describing the scope of disclosed embodiments.