Abstract:
A rack system is disclosed that includes a plurality of electrical modules ( 48 ), a frame ( 10 ) supporting the plurality of electrical modules ( 48 ) that includes a plurality of frame members ( 16, 18, 20, 22, 26, 38, 39, 40 ) and a plurality of locations ( 52 ) for supportably receiving one of the plurality of electrical modules ( 48 ), a first frame member ( 16 ) of the plurality of frame members including a first bore ( 68 ) for transporting a liquid along a length of the first frame member ( 16 ) and having a plurality of openings extending through the first frame member ( 16 ) between a sidewall of the bore ( 68 ) and an exterior surface of the frame member ( 68 ), and a plurality of first connectors ( 64 ) mounted in the plurality of openings, wherein one of the plurality of electrical modules ( 48 ) includes a cooling liquid pathway ( 84 ) and at least one second connector ( 86 ) providing access to the cooling liquid pathway ( 84 ) detachably engaging the first connector ( 64 ) to provide fluid communication between the first bore ( 68 ) and the cooling liquid pathway ( 84 ) when the one of the plurality of electrical modules ( 48 ) is mounted at one of the plurality of locations ( 52 ).

Description:
FIELD OF THE INVENTION 
   The present invention is directed toward an electrical module having an internal cooling liquid passage, a support therefor that includes an integral cooling system, and an assembly of the module and the support, and, more specifically, toward an electrical module, a support such as a rack or cabinet having a cooling liquid manifold formed in a structural element thereof in fluid communication with a cooling passage in the module, and an assembly of the module and the support. 
   BACKGROUND OF THE INVENTION 
   Electrical modules, which may comprise line replaceable modules (LRM&#39;s), may include internal cooling passages for carrying a cooling liquid, such as water, through the module. In use, these modules are connected to sources of cooling liquid and to power sources using a variety of hoses or pipes and wires. 
   Modules are sometimes mounted in a cabinet or on a rack with other LRM&#39;s. This arrangement is space-efficient, but concentrates many heat sources in a small, often enclosed, area, making it important that each module receives an adequate supply of cooling liquid. Mounting the modules in close proximity to each other, however, makes it difficult to connect and disconnect each module to a source of cooling liquid and/or power. It is therefore desirable to provide improved electrical modules and supports that allow for easy interconnection as well as systems of such modules and supports. 
   SUMMARY OF THE INVENTION 
   These difficulties and others are addressed by the present invention which comprises, in a first aspect, an electrical cabinet having a plurality of support members, one of which comprises a first cooling liquid manifold. A plurality of connectors is provided on the support member which selectively provide access to the cooling liquid manifold. 
   Another aspect of the invention comprises a rack for supporting a plurality of electrical modules which rack includes a frame having a plurality of frame members defining a plurality of locations for supportably receiving an electrical module. A first one of the frame members comprises a first manifold, and a plurality of first connectors are provided on the first frame member for selectively providing access to the first manifold. 
   A further aspect of the invention comprises a rack system that includes a plurality of electrical modules, at least one of which has a cooling liquid pathway and a connector for providing access to the cooling liquid pathway. The rack system also includes a frame supporting the plurality of electrical modules and has a plurality of frame members and a plurality of locations supportably receiving one of the plurality of electrical modules. At least one of the frame members comprises a first manifold, and a plurality of second connectors are provided on that support member to selectively provide access to the first manifold. The first connector is detachably connected to the second connector to provide fluid communication between the first manifold and the cooling liquid pathway when one of the plurality of electrical modules is mounted at one of the plurality of locations. 
   Another aspect of the invention comprises a rack-mountable electrical module having a housing having an internal cooling liquid conduit. A first cooling liquid connector on the module selectively provides access to the cooling liquid conduit when pressed against a second cooling liquid connector. A first electrical connector forms an electric connection with a source of electricity when the first cooling liquid connector is pressed against the second cooling liquid connector. 
   An additional aspect of the invention comprises a rack system that includes a plurality of electrical modules and a frame supporting the plurality of electrical modules. The frame has a plurality of frame members defining a plurality of locations for supportably receiving one of the plurality of electrical modules. A first frame member includes a first bore for transporting a liquid along a length of the first frame member and a plurality of openings extending through the first frame member between a sidewall of the bore and an exterior surface of the frame member. A plurality of first connectors are mounted in the plurality of openings. One of the plurality of electrical modules comprises a cooling liquid pathway and at least one second connector providing access to the cooling liquid pathway that is detachably connectable to the first connector to provide fluid communication between the first bore and the cooling liquid pathway when the module is mounted at one of the plurality of locations. 
   A further aspect of the invention comprises a method of supplying a cooling liquid to an internal cooling liquid passageway of a rack-mountable electrical module that involves providing a rack comprising a support member having a longitudinal bore and a plurality of first connectors selectably providing access to the bore. A second connector on the rack mountable electrical module is aligned with a first one of the plurality of first connectors on the support member and the module is slid relative to the support member until the second connector engages the first connector. 
   An additional aspect of the invention comprises an electrical cabinet that includes a frame arrangement including a plurality of supports for supporting a plurality of electrical modules and a heat dissipation arrangement incorporated in at least one of the plurality of supports for carrying a cooling fluid to electrical modules mounted in the frame arrangement. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These aspects of the invention and others will be better understood upon a reading of the following detailed description of an embodiment of the invention in connection with the drawings, wherein: 
       FIG. 1  is a perspective view of a support rack according to an embodiment of the present invention; 
       FIG. 2  is a sectional front elevational view taken in the direction of arrows II-II in  FIG. 1 ; 
       FIG. 3  is a perspective view of the support rack of  FIG. 1  with a plurality of electrical modules mounted thereon; 
       FIG. 4  is a perspective view of an electrical cabinet including the support rack of  FIG. 1 ; 
       FIG. 5  is a rear perspective view of one of the electrical modules of  FIG. 3 ; 
       FIG. 6  is a side elevational view of the module of  FIG. 5  in the process of being mounted on the rack of  FIG. 1 ; and 
       FIG. 7  is an elevational view of a vertical support member for the primary rack that includes a bore and a plug dividing the bore into first and second portions. 
   

   DETAILED DESCRIPTION 
   Referring now to the drawings, wherein the showings are for purposes of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting same,  FIG. 1  illustrates a rack or frame  10  comprising a primary rack  12  and a secondary rack  14  joined to primary rack  12 . Primary rack  12  is comprised of a plurality of frame members or support members including four vertical support members or legs, namely, a left rear leg  16 , a right rear leg  18 , a left front leg  20  and a right front leg  22  (“left,” “right,” “front” and “rear” being used with respect to the orientation of rack  10  in  FIG. 1 ). The legs are interconnected by upper horizontal braces  26  and lower horizontal braces  28 , sometimes referred to herein as cross members. Legs  16 ,  18 ,  20 , and  22 , and many other elements of rack  10  may be made from extruded aluminum, which provides rigidity for the rack  10 . 
   Secondary rack  14  includes a right rear leg  30  generally parallel to left rear leg  16  of primary rack  12  and a right front leg  32  approximately the same length as secondary rack right rear leg  30 . Secondary rack  14  further includes a left rear leg  34  and a left front leg  36  both of which are substantially shorter than the secondary rack right legs  30 ,  32 . The secondary rack legs are joined by upper horizontal supports  38  and lower horizontal supports  40  and middle horizontal supports  39 . 
     FIG. 4  illustrates the mounting of rack  10  in a rounded fuselage  42  of an aircraft, the racks being mounted behind panels  44 , which may be honeycombed panels, to form cabinets enclosing the rack  10 . The rack legs, including legs  16 ,  18 , form the main structural backbone of the cabinet and also provide primary mounting hardpoints for securing rack  10  to the fuselage or other structure. Racks used in different environments may have different configurations from rack  10  without exceeding the scope of the present invention. 
   Primary rack  12  includes a plurality of angle brackets  46  that extend between the left rear leg  16  and the left front leg  20  and between the right rear leg  18  and the right front leg  22 . Pairs of these angle brackets  46  define slideways for supporting generally rectangular electrical modules  48  illustrated, for example, in  FIG. 3  and  FIG. 5 , and support panels  50  which help define locations  52   a - 52   f  for receiving electrical modules  48  in the rack  10 . Secondary rack  14  also includes angle brackets  46  for slidably receiving electrical modules  48  in two additional locations  52   g  and  52   h . More of fewer locations can be provided, depending on the number of modules required and the space available for mounting rack  10 . The angle brackets  46  of primary rack  12  are arranged to define locations  52   a - 52   f  for receiving modules  48  in a generally horizontal orientation—that is, with the long dimension of the rectangular module normal to the primary rack legs  16 ,  18 ,  20 ,  22 . The angle brackets  46  of secondary rack  14  are arranged to receive the modules  48  in a generally vertical orientation, that is, with the long dimension of the modules  48  generally parallel to secondary rack legs  30 ,  32 ,  34 ,  36 . 
   A control card cage  54  is also provided in secondary rack  14  which is a central location for storing control cards for the modules  48 . Providing a central location for control cards allows for ready access, ease of maintenance and simplified shielding. The card cage  54  may be subdivided to allow for an internal firewall if needed and separate motherboards as required. The card cage  54  is liquid cooled and includes an upper manifold  56  and a lower manifold  58  each of which provides cooling liquid to separate cooling circuits (not shown) in the card cage  54  and each of which includes a connector  60  for connection to a source of cooling liquid, such as water or a propylene glycol and water mixture, as described herein. 
   Elements, such as rear legs  16 ,  18  of primary rack  12  are required to support modules  48 , and the present inventors have found a way to use these structural elements as fluid flow conduits. This reduces the need for connecting pipes and tubes to the various modules in the rack. Horizontal supports such as secondary rack middle support  39  and secondary rack lower support  40  are also structural, although they may or may not be load bearing, and may also include internal bores for carrying cooling liquid. The location of the modules is not fixed and it may be possible to move a module from one location to another without substantially changing the operation of the system. However, for ease of reference herein, any module mounted at a particular location will be referred to with the numeral  48  and the same letter suffix as the location, for example the module located at location  52   a  will be referred to as module  48   a.    
   In the present embodiment, rear legs  16 ,  18  of primary rack  12  include internal bores defining conduits for carrying cooling fluid in one or more independent fluid flow paths. The number and arrangement of the flow paths and the number of connections to sources of cooling fluid can be changed without exceeding the scope of this invention. A plurality of connectors selectively provide access to the conduits including a main connector  62  for connecting primary rack  12  to a source of cooling liquid and a plurality of module connectors  64  located in pairs on rear legs  16 ,  18  in each location  52 . The connectors  62 ,  64  are preferably quick disconnect dry break couplings. Suitable connectors are available from several sources, including the Aeroquip group of Eaton Corporation, located in Maumee, Ohio, as part numbers 70575g and 71887g. 
   With reference to  FIG. 2 , a first flow path, which provides cooling liquid to modules mounted in the upper three locations  52   a ,  52   b  and  52   c  of primary rack  12  includes a first conduit  68  in left rear leg  16  and a second conduit  70  in right rear leg  18 . A second flow path, for providing cooling liquid to modules  48  mounted on the lower three locations  52   d ,  52   e  and  52   f  of rack  12  includes a third conduit  72  in left rear leg  16  and a fourth conduit  74  located in right rear leg  18 . A third flow path, for cooling modules mounted in secondary rack  14  includes a fifth conduit  76  in middle horizontal support  39  and a sixth conduit  78  in lower horizontal support  40 . These flow paths may be formed in various manners. One suitable method for forming the different flow paths is to provide extruded aluminum legs  16   18 , for example, having bores extending completely through the length thereof and then welding, swaging, or otherwise securing one or more plugs  77  illustrated in  FIG. 7  in the bores to divide them into separate flow paths. Fluid flow through these flow paths will be described below after a description of modules  48 . 
   Referring again to  FIGS. 2 and 3 , a plurality of modules  48  are illustrated mounted in primary rack  12  and secondary rack  14  in  FIG. 3 . As illustrated in  FIGS. 5 and 6 , each module  48  includes a front  80 , a rear  82  including a guide pin hole  83  and an angled wall portion  85 , an internal cooling liquid flow path  84  and two connectors  86  of a first type providing access to the cooling liquid flow path  84  and allowing for connection to complementary connectors of a second type, such as module connectors  64  on legs  16  and  18 . The modules further include a plurality of electrical connectors  88  near module front  80  that include captive bolts  89  for holding connectors  88  against an electrical bus described hereafter. A connecting bolt  91 , illustrated in  FIG. 6 , holds module  48  securely to rack  10  and holds connectors  86  firmly against connectors  64 . The modules, or LRM&#39;s, may be of a variety of types including, for example, high power, high heat dissipation electrical devices such as motor controllers, inverters or related devices. 
   As will be appreciated from  FIG. 6 , the fluid connectors  86  on the modules  48  connect to the connectors  64  on the rear legs  16 ,  18  when a module  48  is slidingly inserted into a location  52  on rack  10  and the connectors  86  on the module are pressed against the connectors  64  on the legs. A guide pin  101  on rear leg  16  is received in guide pin hole  83  to help align the module with the connectors in the rack. Moreover, rear leg  16  includes an angled surface  103  that is engaged by angled wall  85  on module  48  as module  48  is moved toward the rear of rack  10  to help hold the rear portion of module  48  in place. 
   When modules  48  are mounted in rack  10 , the internal module cooling liquid flow path  84  of each modules forms part of the first, second and third flow paths mentioned above. For example, when module  48  is mounted in location  52   a  the internal cooling flow path  84  connects first conduit  68  to second conduit  70 . Modules  48   b  and  48   c  likewise connect first conduit  68  to second conduit  70  at two additional locations to form three parallel connections between first conduit  68  and second conduit  70 . Fluid flows into main connector  62  and into second conduit  70 , splits into three flows through each of the modules  48   a ,  48   b ,  48   c , flows into first conduit  68  and exits the flow path through exit  88 . This first cooling flow path could include a greater or lesser number of modules if desired and is not limited to the three modules shown. 
   A second cooling flow path cools modules  48   d ,  48   e  and  48   f  mounted at the lower three locations  52   d ,  52   e ,  52   f  of primary rack  12 . This second path provides a series connection between the modules and the conduits. Specifically, cooling liquid enters the second cooling flow path through a connector  90  and passes through a short conduit  92  to a connector  64  and into module  48   d , through the internal cooling path  84  of module  48   d  and into third conduit  72 . Module  48   e  is connected to third conduit  72  and receives cooling liquid therefrom which cooling liquid exits module  48   e  into fourth conduit  74 . Module  48   f  is connected to fourth conduit  74 , and cooling liquid passes through the internal cooling path of module  48   f  to a short conduit  93  which ends at exit connector  94 . Such series cooling may sometimes be desirable, especially when the modules being cooled differ significantly in the heat outputs. 
   Modules  48   g  and  48   h  are connected between fifth conduit  76  and sixth conduit  78  in a similar manner. Fifth conduit  76  is connected to lower manifold  58  of the card cage by connectors  96 . Connectors  60  connect upper manifold  56  of control card cage  54  to first conduit  68  and lower manifold  58  of card cage  54  to fifth conduit  76  as illustrated in  FIG. 2 . This connection to two separate sources of cooling fluid provides a higher lever of cooling and also redundant cooling for the temperature-sensitive control cards. 
   Rack  10  further includes a modular electrical bus  100  illustrated in  FIG. 1  for carrying power and/or control signals to modules  48  which bus  100  includes electrical connectors  102 . Bus  100  can be removed from rack  10  for repair or replacement. Referring to  FIG. 6 , it will be appreciated that electrical connectors  88  on modules  48  engage to bus connectors  102  when the module slides into one of the locations  52  and are secured thereto by captive bolts  89 . This allows for electrical and fluid connections to be made as a single step in the installation process. Separating the electrical connectors  102  from the fluid connectors  86  reduces the likelihood of contact between water and the electrical connectors in the event that a connector leaks. Moreover, the electrical connectors are maintained in an accessible location at the front of rack  10  where they can readily be reached for repair or service. 
   By integrating cooling manifolds into the structural elements of a rack or cabinet, the number of parts and potential failure points are reduced, and the ease of use is increased. Structural strength is concentrated into rigid members that carry both internal and structural loads, and the wide mounting areas reduce the load bearing requirements on other supports in the environment—aircraft structural elements, for example. The legs, such as rear legs  16  and  18  provide strength for supporting the electrical modules and also attachment points for securing rack  10  to, e.g., an aircraft frame. 
   The present invention has been described in terms of several embodiments. Obvious modifications and additions will become apparent to those skilled in the relevant arts upon a reading of the foregoing disclosure and such modifications and additions are intended to comprise a part of the present invention to the extent they fall within the scope of the several claims appended hereto.