Patent Document

BACKGROUND OF THE INVENTION 
     The subject matter disclosed herein relates to the art of electrical enclosures and, more particularly, to an interlock system for a shutter that separates a bus bar portion from an electrical component portion of an electrical enclosure. 
     In general, a switchgear serves as an interface between an electrical supply and an electrical load. The switchgear is arranged in an enclosure that includes a line or busbar portion and a load or circuit breaker portion. The busbar portion includes one or more busbars that are connected to the electrical supply. The circuit breaker portion includes one or more circuit breakers that are electrically connected to the one or more busbars and an electrical load. The circuit breaker is configured to interrupt a flow of current from the one or more busbars to the electrical load in the event of an over-current condition, short circuit condition and/or an over/under voltage condition. Generally, the enclosure includes a shutter that separates the bus bar portion from the circuit breaker portion. When the circuit breaker is removed, the shutter closes off access to the bus bar portion from the circuit breaker portion. 
     BRIEF DESCRIPTION OF THE INVENTION 
     According to one aspect of an exemplary embodiment, an electrical enclosure for an electrical component includes a housing having a bus bar portion and an electrical component portion arranged to receive the electrical component. At least one shutter is moveably arranged between the bus bar portion and the electrical component portion. A shutter interlock is arranged in the electrical component portion. The shutter interlock is configured and disposed to prevent the at least one shutter from shifting from a closed position to an open position when the electrical component is absent from the electrical component portion of the housing. 
     According to another aspect of an exemplary embodiment, a switchgear for a circuit breaker includes a housing having a bus bar portion and a circuit breaker portion arranged to receive the circuit breaker. A first circuit breaker support rail is arranged in the circuit breaker portion and a second circuit breaker support rail is arranged in the circuit breaker portion spaced from the first circuit breaker support rail. The first and second circuit breaker rails are arranged to support the circuit breaker in the circuit breaker portion. At least one shutter is arranged in the housing between the bus bar portion and the circuit breaker portion. The at least one shutter is selectively moveable between an open position and a closed position. At least one shutter interlock is pivotally mounted to one of the first and second circuit breaker support rails. The at least one shutter interlock is configured and disposed to prevent the at least one shutter from shifting from the closed position to the open position when the circuit breaker is absent from the circuit breaker portion of the housing. 
     These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a perspective view of an electrical enclosure including a bus bar portion and an electrical component portion, in accordance with an exemplary embodiment; 
         FIG. 2  is an interior view of the electrical enclosure illustrating first and second shutters separating the bus bar portion from the electrical component portion in a closed position; 
         FIG. 3  is an interior view of the electrical enclosure of  FIG. 2  illustrating the first and second shutters shifting to an open position upon insertion of an electrical component in the electrical component portion upon first and second component support rails; 
         FIG. 4  is a perspective view of one of the component support rails of  FIG. 3  including a shutter interlock, in accordance with an exemplary embodiment; 
         FIG. 5  illustrates the shutter interlock of  FIG. 4  in a deployed position blocking movement of the first and second shutters from the closed position; 
         FIG. 6  illustrates the electrical component of  FIG. 3  engaging the shutter interlock; and 
         FIG. 7  illustrates the electrical component shifting the shutter interlock to a non-deployed position. 
     
    
    
     The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     An electrical enclosure, in accordance with an exemplary embodiment, is indicated generally at  2 , in  FIG. 1 . Electrical enclosure  2  is shown in the form of a switchgear  3  having a housing  4 . Housing  4  includes a bus bar portion  6  that houses one or more electrical busses (not shown) and an electrical component portion  8 . Housing  4  also includes a shutter system  10  that provides a selectively moveable barrier between bus bar portion  6  and electrical component portion  8 . Shutter system  10  includes a first selectively shiftable shutter  12  and a second selectively shiftable shutter  14 . 
     Shutter system  10  includes a first operating mechanism  16  and a second operating mechanism  17  that selectively opens and closes first and second shutters  12  and  14 . As each operating mechanism  16  and  17  is similarly constructed, a detailed description will follow with reference to  FIG. 2  in describing first operating mechanism  16  with an understanding that second operating system  17  includes corresponding structure. First operating mechanism  16  includes a first operating lever  18  connected to first shutter  12  through a first linking bar  20 . Similarly, a second operating lever  22  is operatively connected to second shutter  14  through a second linking bar  24 . As will be discussed more fully below, first operating lever  18  pivots downwardly opening first shutter  12  and second operating lever  22  shifts upwardly opening second shutter  14 . 
     Housing  4  is also shown to include a first component or circuit breaker support rail  30  and a second component or circuit breaker support rail  32  ( FIG. 1 ). First and second component support rails  30  and  32  extend through electrical component portion  8  toward bus bar portion  6 . In the exemplary embodiment shown, an electrical component  40  ( FIG. 3 ), shown in the form of a circuit breaker  44 , is positioned upon first and second component support rails  30  and  32 . Electrical component  40  includes a support bracket  46  that slidingly engages with first and second component support rails  30  and  32 . In this manner, circuit breaker  44  may be shifted toward bus bar portion  6  allowing a first plurality of terminals  50  and a second plurality of terminals  52  to slide through corresponding openings  56  and  58  ( FIG. 3 ) that are exposed as shutters  12  and  14  open. Terminals  50  and  52  mate with bus bars (not shown) in bus bar portion  6 . More specifically, as circuit breaker  44  slides along component support rails  30  and  32 , support bracket  46  engages with first and second operating mechanisms  16  and  17  to open first and second shutters  12  and  14 . 
     In accordance with an exemplary embodiment, electrical enclosure  2  includes a shutter interlock system  60  that restricts opening of first and second shutters  12  and  14  when electrical component  40  is absent from electrical component portion  8 . Interlock system  60  includes a first shutter interlock  64  mounted to first component support rail  30 . A second shutter interlock (not separately labeled) may be mounted to second component support rail  32 . As will be discussed more fully below, shutter interlock  64  pivots between a deployed position preventing shutters  12  and  14  from opening to a non-deployed position allowing shutters  12  and  14  to open when acted upon by an interlock engagement member  70  provided on electrical component  40 . Interlock engagement member  70  may take the form of a leading edge (not separately labeled) and an outwardly facing surface (also not separately labeled) 
     As best shown in  FIG. 4 , shutter interlock  64  extends from a first end  80  to a second end  81  through an intermediate portion  83 . First end  80  is pivotally mounted to first component support rail  30  through an axel or pin  86  that nests within a bushing  88 . Second end  81  includes a shutter locking plate  92  that extends between first and second operating levers  18  and  22  to prevent shutters  12  and  14  from opening. Pin  86  defines an axis of rotation of the shutter interlock and extends from a first end (not shown) that nests within bushing  88  to a second end  97  that is connected to first component support rail  30  by an interlock support  100 . A return spring  104  extends around an upper portion of pin  86  between first end  80  of shutter interlock  64  and interlock support  100 . More specifically, return spring  104  extends from a first end section  107  connected to first end  80  of shutter interlock  64  to a second end section  108  that connects with interlock support  100 . In this manner, return spring  104  biases shutter interlock  64  in the deployed configuration, such as shown in  FIG. 5 . 
     Shutter interlock  64  also includes an activation member  120  that is acted upon by interlock engagement member  70 , as shown in  FIG. 6 . In accordance with an aspect of the exemplary embodiment, activation member  120  may include a roller  124  to reduce drag forces between shutter interlock  64  and interlock engagement member  70 . When electrical component  40  is inserted into electrical component portion  8 , support bracket  46  engages with activation member  120  through roller  124  initiating a pivoting of shutter interlock  64  ( FIG. 6 ). Continued insertion of electrical component  40  causes support bracket  46  to engage with activation member  120  pivoting shutter interlock  64  from a deployed position ( FIG. 5 ) to a non-deployed position ( FIG. 7  in which shutters  12  and  14  are free to open. Once shutter interlock  64  is shifted to the non-deployed position, shutters  12  and  14  may open, and terminals  50  and  52  may engage with bus bars (not shown) in bus bar portion  6 . 
     At this point it should be understood that the exemplary embodiments provide an interlock system that constrains opening of shutters that separate a bus bar portion from an electrical component portion of an electrical enclosure. The interlock system may be arranged on a single component support rail, or as shown, be arranged on each component support rail. However, it should be understood that the interlock system may be arranged in other portions of the enclosure that are exposed to an electrical component. Further, while the activation member is shown to include a roller, other mechanisms may be used to engage with an electrical component support rail. 
     While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Technology Category: h