Abstract:
A vented exhaust system for an electrical cabinet housing high voltage equipment. Very short-time explosions can occur within the electrical cabinet that are the result of a short circuit of the equipment housed within. The vented exhaust system provides for a way to safely release the pressure and hot gasses that can result from the short circuit so that the cabinet does not explode.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 62/029,285, filed on Jul. 25, 2014, the contents of which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    In general, the present invention relates to a vented exhaust system for an electrical cabinet, such as a cabinet that houses high voltage electrical equipment used in public electricity distribution. 
       BACKGROUND OF THE INVENTION 
       [0003]    Electrical cabinets that house high voltage electrical equipment, such as switchgear, that are used for public electricity distribution must have the ability to vent, exhaust or otherwise controllably release pressure and hot gases that can occur inside the cabinet in case of a very short-time explosion which can be the result of a short circuit of the equipment that is housed within. Some solutions already exist, but a less expensive and safer alternative is desired. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention provides a triple-wall vented exhaust system for an electrical cabinet, such as a cabinet that houses high voltage electrical equipment used in public electricity distribution. An inner plate is located within the cabinet that houses the high voltage electrical equipment and comprises the first wall. The middle wall of the triple-wall vented exhaust system is comprised of louvers which are located within the wall of the cabinet panel housing. The third wall is a deflector plate that is located outside of the wall of the cabinet panel housing. The combination of the inner plate, the louvers and the outer deflector plate comprise the triple-wall vented exhaust system. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a side elevation cross-sectional view of the triple-wall vented exhaust system for an electrical cabinet of the present invention. 
           [0006]      FIG. 2  is a side elevation cross-sectional view of the triple-wall vented exhaust system for an electrical cabinet of the present invention showing air flow through the system. 
           [0007]      FIG. 3  is a plan view of the triple-wall vented exhaust system for an electrical cabinet of the present invention. 
           [0008]      FIG. 4  is a rear elevation view of the triple-wall vented exhaust system for an electrical cabinet of the present invention showing air flow through the system. 
           [0009]      FIG. 5  is a front elevation view of the triple-wall vented exhaust system for an electrical cabinet of the present invention showing air flow through the system. 
           [0010]      FIG. 6  is a front elevation view an electrical cabinet with a triple-wall vented exhaust system of the present invention showing air flow through the system. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0011]    The above and other features, aspects and advantages of the present invention will now be discussed in the following detailed description of preferred embodiments and appended claims, which are to be considered in conjunction with the accompanying drawings in which identical reference characters designate like elements throughout the views. 
         [0012]    Shown in  FIG. 1  is a side elevation cross-sectional view of a triple-wall vented exhaust system  101  for an electrical cabinet of the present invention. The vented exhaust system  101  includes an inner plate  125 , a plurality of louvers  135  and an outer plate  143 . The vented exhaust system  101  may be located in one or many locations on an electrical cabinet  103 , such as shown in  FIG. 6 . In  FIG. 6 , the vented exhaust system  101  is shown to be located on a front wall  107  of the electrical cabinet  103 , but it may be located on a top wall  111 , a side wall  115  or  117 , a bottom wall  113 , or a rear wall  109  (not shown). The inner plate  125  of the vented exhaust system  101  is attached to an inner surface  119  of the cabinet wall  107  and is spaced a first distance  127  from the inner surface  119  of the cabinet wall  107  with spacers  129 . Because of the spacers  129  which allow the inner plate  125  to be spaced a first distance  127  from the inner surface  119  of the cabinet wall  107 , the inner plate is open on all four sides to the space within the cabinet. In  FIG. 4 , four spacers  129  are shown to be used, one at each corner of the inner plate  125 , to space the inner plate  125  the first distance  127  from the inner surface  119  of the cabinet wall  107 . However, it is understood that more or fewer spacers  129  may be used. The inner plate  125  is attached to the inner surface  119  of the cabinet wall  107  by means of threaded weld studs  131  and nuts  133 , also shown in  FIG. 1 . Similarly to the spacers  129 , there are four sets of threaded weld studs  131  and nuts  133  shown to attach the inner plate  125  to the inner surface  119  of the cabinet wall  107 , one set at each corner of the inner plate  125 . However, it is understood that more or fewer sets of threaded weld studs  131  and nuts  133  may be used. The inner plate  125  comprises the first wall of the triple wall vented exhaust system  101 . 
         [0013]    The second and middle wall of the triple wall vented exhaust system  101  is includes a plurality of louvers  135  which are integrally contained within the wall  107  of the cabinet and are positioned immediately adjacent and parallel to the inner plate  125 . The louvers  135  are positioned such that they direct any airflow exiting the louvers  135  in a downward position. This airflow  141  exiting the louvers  135  is shown in  FIG. 2 . The airflow  141  is caused by a very short-time (less than 1 second) short circuit explosion  123  which can sometimes occur in electrical cabinets which house high-voltage electrical equipment. When the short circuit  123  occurs, the resulting pressure and hot gases released from the short circuit explosion  123  are able to escape around the inner plate  125 , previously described, which is open on all four sides and then directed through the plurality of louvers  135  in a downward direction. 
         [0014]    In  FIGS. 1 and 2  the louvers  135  which are integrally contained within the wall  107  of the cabinet are shown to be fixed, and remain open between the inside and outside of the cabinet at all times. However, it is understood that the louvers  135  could serve the same purpose as previously described if they were movable about a horizontal axis such that they would be allowed to move in an outward direction away from the cabinet interior from a closed position into an open position when sufficient airflow  141 , caused by a short circuit explosion  123  within the cabinet, contacts the louvers  135  from within the cabinet. Then, when the airflow  141  ceased due to the complete release of pressure and gases from the short circuit explosion  123 , the louvers  135  would return to a closed position by rotating about a horizontal axis until they came to rest at a position parallel to the cabinet wall  107 . 
         [0015]    The third and last wall of the triple wall vented exhaust system  101 , also shown in  FIGS. 1 and 2 , includes an outer plate  143 . The outer plate  143  is welded to an outer surface  121  of the cabinet wall  107  and is positioned immediately adjacent and parallel to the louvers  135 . The outer plate  143  serves as the last “layer” of the triple wall vented exhaust system to direct pressure and gases out of the electrical cabinet. The outer plate  143  is welded on a top edge  147 , and side edges  149  and  151 , shown in  FIGS. 3 ,  5  and  6 , to the outer surface  121  of the cabinet wall  107 . This leaves a bottom edge  153  of the outer plate  143  open to the outside environment and allows the airflow  141  which is directed out of the louvers  135  to exit from the bottom edge  153  of the outer plate  143 , again directing the airflow  141  in a downward direction. Similarly to the inner plate  125 , the outer plate  143  is spaced a second distance  145  from the outer surface  121  of the wall  107 . 
         [0016]      FIG. 3  shows a plan view of the previously discussed vented exhaust system  101  of the present invention. Again, the inner plate  125 , plurality of louvers  135  and outer plate  143  are shown.  FIG. 4  shows a rear elevation view of the triple-wall vented exhaust system  101  for an electrical cabinet of the present invention with air flow  141  through the system. This rear elevation view is a look from within the electrical cabinet  103 , such as shown in  FIG. 6 . In  FIG. 4 , it can be seen that when a short circuit explosion  123  takes place within the cabinet due to a short circuit of the high-voltage electrical equipment housed within, the resulting air flow  141  that occurs due to the pressure and hot gases released from the explosion can escape around the open edges  125   a,    125   b,    125   c  and  125   d  of the inner plate  125 . The air flow  141  is able to escape around the open edges of the inner plate  125  due to the first distance  127 , shown in  FIGS. 1-3 , that the inner plate  125  is spaced from the wall inner surface  119  of the cabinet. 
         [0017]      FIG. 5  shows a front elevation view of the triple-wall vented exhaust system  101  for an electrical cabinet of the present invention, again with air flow  141  through the system. This front elevation view is a look from outside of the electrical cabinet  103 , such as shown in  FIG. 6 . In  FIG. 5 , it can be seen that the airflow  141 , as mentioned above, is exiting the electrical cabinet from the bottom edge  153  of the outer plate  143 . The top edge  147  and two side edges  149  and  151  of the outer plate  143  are welded to the wall outer surface  121  of the side wall  115  of the electrical cabinet, leaving only the bottom edge  153  open to the outside environment, and thus allowing the airflow  141  to exit in one direction. The air flow  141  is able to escape from the open bottom edge  153  of the outer plate  143  due to the second distance  145 , shown in  FIGS. 1-3 , that the outer plate  143  is spaced from the wall outer surface  121  of the cabinet. The inner plate  125  and the louvers  135 , which are located adjacent, parallel to and behind the outer plate  143  are also shown again in  FIG. 5  in broken lines to represent their location behind the cabinet side wall  115 . 
         [0018]    Finally, shown in  FIG. 6  is an overall view of the electrical cabinet  103  with the vented exhaust system  101 . In  FIG. 6 , it is shown that the electrical cabinet  103  has the vented exhaust system  101  at two locations on the front wall  107  of the electrical cabinet  103 . However, it is understood that the electrical cabinet  103  may have the vented exhaust system  101  located at more or fewer locations on different walls of the electrical cabinet, such as the side walls  115  and  117 , top wall  111 , rear wall  109  (not shown) or bottom wall  113  if the cabinet  103  is elevated from the ground. The vented exhaust system  101  may be on multiple walls and at multiple locations, on a single wall with multiple locations, on multiple walls at a single location or on a single wall at a single location. As previously explained, the high voltage equipment (not shown) that is housed within the cabinet  103  may experience a short circuit which can cause the short circuit explosion  123 . The airflow  141  caused by the pressure and hot gases of the explosion ultimately exits the cabinet  103  through the bottom edge  153  of the outer plate  143 , creating a safe path to release the pressure and hot gases which result from the short circuit explosion  123 . 
         [0019]    Although the invention has been described in detail above, it is expressly understood that it will be apparent to persons skilled in the relevant art that the invention may be modified without departing from the spirit of the invention. Various changes of form, design, or arrangement may be made to the invention without departing from the spirit and scope of the invention. Therefore, the above mentioned description is to be considered exemplary, rather than limiting, and the true scope of the invention is that defined in the following claims.