Abstract:
A compartmentalized electrical power distribution enclosure comprising: a outer enclosure defining an interior; a compartment enclosure disposed within the interior, the compartment enclosure including a plurality of interconnected panels, a panel of the plurality of interconnected panels being removable from the compartment enclosure and replaceable to the compartment enclosure by relative movement of the panel with respect to an adjacent panel without the use of tools, the removal of fasteners or damage to the panel or adjacent panel.

Description:
[0001]     This application claims the benefit of U.S. Provisional Application No. 60/735,751 filed Nov. 11, 2005. 
     
    
     TECHNICAL FIELD  
       [0002]     This patent relates to underground electrical power distribution systems and more particularly to a compartmentalized power distribution equipment enclosure suitable for an underground electrical power distribution system and other applications.  
       BACKGROUND  
       [0003]     In contrast to overhead systems, underground electrical distribution systems transfer energy through buried, insulated cables. The conductors are energized at high potential; the sheathing of the cable is grounded. This creates high electrical stress in the cable insulation. When the cable emerges from the ground and connects to equipment, the conductor must remain sufficiently insulated from ground potential.  
         [0004]     A system providing such a connection passes the conductor, insulation and ground sheath through an elastomeric connector system. The ground sheath is connected to the grounded equipment enclosure. An interior bushing sufficiently grades the electrical stress. However, these systems do not provide a barrier between the cable termination and the device to which it is connected. In other instances, it is desirable to provide for the cable termination to be segregated from other components, such as circuit-breakers, switchgear or buswork, to allow maintenance of grounded cable terminations without exposure to breaker terminals or buswork that might be energized. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]      FIG. 1  is a perspective view of a compartmentalized underground distribution switchgear enclosure.  
         [0006]      FIG. 2  is a perspective view of the enclosure illustrated in  FIG. 1  with a first compartment enclosure access panel displaced to provide access to gear disposed within the compartment enclosure.  
         [0007]      FIG. 3  is a perspective view of the enclosure illustrated in  FIG. 1  with the first compartment enclosure access panel removed.  
         [0008]      FIG. 4  is a perspective view of the enclosure illustrated in  FIG. 1  with the first compartment enclosure access panel removed and a second compartment enclosure access panel displaced to provide access to gear disposed within the compartment enclosure.  
         [0009]      FIG. 5  is a perspective view of the enclosure illustrated in  FIG. 1  with the first and second compartment enclosure access panels removed.  
         [0010]      FIG. 6  is a perspective view of a compartment that may be disposed within the enclosure depicted in  FIG. 1 .  
         [0011]      FIG. 7  is a perspective view of the compartment enclosure depicted in  FIG. 6  with first and second access panels removed.  
         [0012]      FIG. 8  is a perspective view of the compartment enclosure depicted in  FIG. 6  with a first panel positioned for assembly to the compartment enclosure.  
         [0013]      FIG. 9  is an enlarged partial perspective view of a rail construction for interlocking panels of the compartment enclosure depicted in  FIG. 6 .  
         [0014]      FIG. 10  is an enlarged partial rear perspective view of the compartment enclosure depicted in  FIG. 6  illustrating a blocking feature.  
         [0015]      FIG. 11  is a perspective view the compartment enclosure depicted in  FIG. 6  with a first panel removed and illustrating a blocking feature.  
         [0016]      FIG. 12  is a section view taken along line  12 - 12  of  FIG. 11 .  
         [0017]      FIG. 13  is an enlarged detail of a portion of the section illustrated in  FIG. 11 . 
     
    
     DETAILED DESCRIPTION  
       [0018]      FIG. 1  illustrates a compartmentalized underground distribution switchgear enclosure  10 . The enclosure  10  is positioned on a base  12 , such as a concrete or other suitable foundation or base, as is well know. Insulated, buried conductors (not depicted) communicate through the base  12  into the enclosure  10 . The enclosure  10  may include fixed side panels  14  and a fixed top panel  16  along with a pivoting top panel  18  and a retractable front panel  20 . The panel  18  is hinged and mounted to pivot upwardly and to be suitably supported, for example, by a prop rod  22 . With the top panel  18  raised, the retractable front panel  20  may be lowered. In this regard, the panel  20  may include panel members  20   a  and  20 b. The panel member  20   b  may be fixed while the panel member  24  is received in channels  24  formed in the side panels  14 . The panel member  20   a  is moveable within the channels  24  from a raised position (not depicted) to a lowered position as shown in  FIG. 1  to enhance access to the enclosure  10 . The enclosure  10  may further include a control housing  26  secured to one of the side panels  14 . The control housing  26  is suitable for housing control electronics, communication gear and the like separate and apart from the power distribution equipment disposed within the enclosure  10 . The control housing  26  will generally include an enclosing panel (not depicted) to enclose the control housing  26 .  
         [0019]     Referring to  FIGS. 1-5 , disposed within the enclosure  10  may be a compartment enclosure  30 , and as depicted in the figures, the enclosure  10  includes three compartment enclosures  30 . Any number of compartment enclosures may be provided within the enclosure  10 . The compartment enclosures may be retrofitted into existing designs for enclosures, or new enclosure designs may incorporate compartment enclosures. The compartment enclosures  30  segment or compartmentalize the interior space of the enclosure  10  to permit separation of cable termination from other distribution equipment and components contained within the enclosure  10 , such as circuit-breakers, switches, terminations, buswork and the like. As will be described, a plurality of interconnecting panel members forms each compartment enclosure  30 . One or more of the interconnecting panel members may be movable relative to the other panel members. Moreover, the interconnection of the panel members may serve to secure the panel members together to enclose the compartment enclosure  30  without the use of mechanical or other fasteners. Furthermore, the interconnecting of the panels members may further act to facilitate sealing of the edges of the compartment enclosure  30  during a flash over or other failure event of the equipment disposed within the compartment enclosure  30 .  
         [0020]     One or more panel members of the compartment enclosure  30  may be moveable and/or removable to open and provide access to an interior of the compartment enclosure  30  and the equipment disposed therein. Referring to  FIG. 2 , a first panel, e.g., a front panel  32  may be slideable along a first direction relative to the other panel members. As shown in  FIG. 2 , the panel  32  is vertically slideable relative to the compartment enclosure  30  to remove the panel  32  from the compartment enclosure  30 , although it should be understood the direction of movement is freely selectable based upon the orientation of the compartment enclosure  30  within the enclosure and the order in which the panels are to be removed, as will be described.  
         [0021]     Removing the front panel  32  from the compartment enclosure  30  ( FIG. 3 ) creates an access opening  36  providing access to the equipment  34 , such as switches, circuit breakers, terminations, buswork and the like disposed within the compartment enclosure  30 . A second panel, e.g., a top panel  38  may also be slideable relative to the other remaining panel members. As shown in  FIG. 4 , horizontal sliding of the panel  38  forward, relative to and towards the front of the enclosure  10  allows removal of the panel  38  from the compartment enclosure  30 . Removing the top panel  38  increases the size of the access opening  36  ( FIG. 5 ).  
         [0022]     The panels forming the compartment enclosure  30 , and particularly the moveable and/or removable panels such as panel  32  and panel  38 , may be formed with blocking features. The blocking features may limit removal of panels to a defined sequence, e.g., preventing removal of a second panel before removal of a corresponding, locking first panel. Additional blocking features may ensure that the panels be reinserted in the correct positions and orientations. Moreover, as with the arrangement of multiple compartment enclosures  30  depicted in  FIG. 1 , the blocking features may prevent a panel from a one compartment enclosure from being assembled to another compartment enclosure, as will be explained.  
         [0023]      FIG. 6  illustrates a single compartment enclosure  30  removed from the enclosure  10 . In addition to the front panel  32  and the top panel  38 , the compartment enclosure  30  includes side panels  40  and a bracket panel  42 . As shown in  FIG. 7 , the side panels  40  are spaced apart by and are secured by the bracket panel  42  using suitable fastening, such as spot welding, riveting or thread fasteners  44 , as depicted. The bracket panel  42  includes a flange  46  for securing the compartment enclosure  30  within an enclosure, such as the enclosure  10 , and/or to secure the compartment enclosure  30  to a power distribution equipment. Lower edges  50  of the side panels  40  may also be flanged to facilitate securing the compartment enclosure  30  within the enclosure. The side panels  40  and the bracket panel  42  define an opening  48  at a rear of the compartment enclosure  30  that may be filled by the equipment to be disposed within the compartment enclosure  30 . An opening  49  is also defined at the bottom of the compartment enclosure  30  through which conductors may be routed for connection to the equipment contained within the compartment enclosure  30 . As will be appreciated, either or both of the openings  48  and  49  may be enclosed, and other suitable access to the interior of the compartment enclosure  30  provide by forming one or more apertures in another panel of panels of the compartment enclosure  30 .  
         [0024]     Referring to  FIGS. 8 and 9 , front edges  52  of the side panels  40  are formed to include channels or rails  54 . Side edges  56  of the front panel  32  are formed with complimentary channels or rails  58 . The rails  58  are slideably received within the rails  54  such that the front panel  32  is secured to the compartment enclosure  30 . The interlocking engagement of the rails  54  and the rails  58  provides substantial structural integrity in securing the front panel  32  to the compartment enclosure  30 . Moreover, sliding engagement of the front panel  32 , and the corresponding interlocking engagement of the rails  54  and the rails  58  permits securing of the front panel  32  to the compartment enclosure  30  without separate fasteners or tools.  
         [0025]     Continuing to refer to  FIG. 8  and now referring also to  FIG. 10 a  front edge  60  of the top panel  38  includes a notch or relief  62  offset from the center of the top panel  38  and hence the center of the compartment enclosure  30 . An inner surface  64 , relative to the interior of the compartment enclosure  30  as depicted in the figures, includes a post  66 , offset from the center of the front panel  32 /compartment enclosure  30  a corresponding distance as the notch  62  is offset from the center of the top panel  38 . The post  66  is also offset from the bottom of the front panel  32 . The rails  58  may be aligned and engaged with the rails  54  to secure the front panel  32  to the compartment enclosure  30 . However, unless the post  66  aligns with the notch  62 , the front panel  32  cannot be slide along the rails the required distance to secure it in its assembled position as depicted in  FIG. 6 . Thus, the notch  62  and post  66  arrangement provides a blocking feature that prevents an incorrect front panel from being assembled to a compartment enclosure  30 . When multiple compartment enclosures  30  are provided within an enclosure, each may be provide with a blocking feature, such as the described notch  62  and post  66 . However, the offset of the blocking feature from the center of the compartment enclosure  30  may be different for each compartment enclosure  30  preventing an incorrect panel from being assembled to a compartment enclosure  30 .  
         [0026]     Similar rail-to-rail assembly and blocking features may be employed for assembly of the top panel  38  to the side panels  40 . Referring to  FIGS. 11 and 12 , the edges  70  of the top panel  38  includes rails  72 . The top edges  74  of each of the side panels  40  include rails  76 . The rails  76  are slideably received within the rails  72  such that the top panel  38  is secured to the compartment enclosure  30 . The interlocking engagement of the rails  72  and the rails  76  provides substantial structural integrity in securing the top panel  38  to the compartment enclosure  30 . Moreover, sliding engagement of the top panel  38 , and the corresponding interlocking engagement of the rails  72  and the rails  76  permits securing of the top panel  38  to the compartment enclosure  30  without separate fasteners or tools.  
         [0027]     The interlocking engagement of the rails  72  with the rails  76  occurs along substantially the entire length of the top panel  38 . In a similar manner, the interlocking engagement of the rails  54  and the rails  58  occurs along substantially the entire height of the front panel  32 . The interlocking rail-to-rail engagement of the front panel  32 , the top panel  38 , or any other panel that is intended to be removed from the compartment enclosure  30 , provides a strong structural engagement of the removable panel with the compartment enclosure. Moreover, forces bearing outwardly on the interior walls of the panels  32 ,  38 ,  40  and  42  will tend to lock the rails together further enhancing the structural integrity of the compartment enclosure  30 . While  FIG. 12  illustrates the rail-to-rail engagement of the rails  72  with the rails  76 , the illustrated section may be employed for the rail-to-rail engagement of the rails  54  with the rails  58 . However, alternative interlocking flanges may be employed. The rails  72  may include rolled flange  78  having a first surface  80 , a second surface  82  and a third surface  84  at an acute angle to the second surface  82 . The rails  76  may include a rolled flange  86  having a first surface  88  and a second surface  90 . In the event of a failure of a component with the compartment enclosure  30  resulting in a flashover or similar event, the increase in internal pressure within the compartment enclosure  30  presses outwardly on the panels. The surface  88  is pressed against the surface  80  while the surface  90  is pressed against the surface  88  as a result of the internal pressure. The rail-to-rail engagement of the panels locks the panels together structurally, but moreover, the surface-to-surface engagement provides a seal along the edges of the front panel  32  and the top panel  38  with the side panels  40 . A flange  90  of the back panel  42  may extend over the top panel  38  to further enhance sealing of the compartment enclosure  30 .  
         [0028]     Referring to  FIGS. 11 and 13 , the flange  90  of the back panel  42  includes a notch or relief  92  offset from the center of the back panel  42 . A surface  94  of the top panel  38  includes a post  96 , offset from the center of the top panel  38  a distance corresponding to the distance the notch  92  is offset from the center of the back panel  42 . The post  96  is disposed toward a rear edge  98  of the top panel  38 . The rails  76  may be aligned with the rails  72  to secure the top panel  38  to the compartment enclosure  30 . However, unless the post  96  aligns with the notch  92 , the top panel cannot be secured in its assembled position as depicted in  FIG. 6 . Thus, the notch  92  and post  96  arrangement provides a blocking feature that prevents an incorrect top panel from being assembled to a compartment enclosure  30 . When multiple compartment enclosures  30  are provided within an enclosure, each may be provide with a blocking feature, such as the described notch  92  and post  96 . However, the offset of the blocking feature from the centerline of the compartment enclosure may be different for each compartment enclosure  30  preventing an incorrect top panel from being assembled to a compartment enclosure  30 .  
         [0029]     While only a single pin and notch are described as providing a blocking feature, multiple pins and notches may be provided to define a single blocking feature for a panel, such as the front panel  32 , the top panel  38  or another panel intended to be removed from and assembled to the compartment enclosure. The pins may be staked to the panel by plastic deformation of an end of the pin extending through an aperture formed in the panel, or the pins may be attached by any other suitable means such as by welding or threaded fastener.  
         [0030]     Additional features of the compartment enclosure  30  are illustrated in the figures. In  FIG. 1 , the front panel  32  is shown to include one or more handles  100  and/or labels  102 . The top panel  38  may include a label  104 . The handles and labels assist an operator in removing panels and replacing them to the correct compartment enclosure. The labels further identify to the operator the equipment disposed within the compartment enclosure without the operator removing a panel to visually inspect the equipment. The blocking features prevent the panels from being assembled to the incorrect compartment enclosure  30 , and hence the panel and corresponding labels from being associated with the wrong equipment. Additional blocking features may be provided to prevent panels from being removed except in a predetermined order. As seen in  FIG. 1  and  FIG. 6 , the front panel  32  may include a flange  106  that overlaps the top panel  38 . The flange  106  provides a blocking feature that prevents the top panel  38  from being removed unless the front panel  32  is first removed.  
         [0031]     A compartment enclosure may be used in connection with underground distribution switchgear enclosures and other suitable power distribution enclosures. The compartment enclosures may segment a larger underground switchgear enclosure allowing terminations, breaker/switches, buswork and the like to be separated within the larger switchgear enclosure. Moreover, the compartment enclosures remain at ground potential. The compartment enclosures may include one or more panels that include interlocking assembly features, such as rail-to-rail type engagement features, allowing the panels to be assembled to the compartment enclosure without tools or fasteners. The interlocking assembly features may interlock so that in the event of a component failure within the compartment enclosure and a corresponding potential increase in internal pressure, the interlocking assembly features lock together to increase mechanical strength of the compartment enclosure and to seal the compartment enclosure. Blocking features may furthermore be included to ensure correct panel assembly and disassembly.  
         [0032]     While the present disclosure is susceptible to various modifications and alternative forms, certain embodiments are shown by way of example in the drawings and the herein described embodiments. It will be understood, however, that this disclosure is not intended to limit the invention to the particular forms described, but to the contrary, the invention is intended to cover all modifications, alternatives, and equivalents defined by the appended claims.  
         [0033]     It should also be understood that, unless a term is expressly defined in this patent using the sentence “As used herein, the term ‘______’ is hereby defined to mean . . . ” or a similar sentence, there is no intent to limit the meaning of that term, either expressly or by implication, beyond its plain or ordinary meaning, and such term should not be interpreted to be limited in scope based on any statement made in any section of this patent (other than the language of the claims). To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term by limited, by implication or otherwise, to that single meaning. Unless a claim element is defined by reciting the word “means” and a function without the recital of any structure, it is not intended that the scope of any claim element be interpreted based on the application of 35 U.S.C. §112, sixth paragraph.