Patent Document

This application claims the benefit of U.S. Provisional Application No. 60/165,414 filed on Nov. 13, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to the field of protective devices and systems for electrical power transmission and distribution systems, and more particularly to a current transfer arrangement for a circuit interrupter that provides support for the contacts of the circuit interrupter and also provides current transfer between the contacts of the circuit interrupter and the external circuit terminal connection points directly through the end flanges/fittings thereof. 
     2. Description of the Related Art 
     Various electrical connection arrangements are know for connecting the contacts of protective devices such as fuses, circuit interrupters and circuit breakers to the electrical circuit terminals of electrical power transmission and distribution systems. Typically, these arrangements involve the end closures of gas-tight enclosures. 
     While the prior art arrangements may be useful to provide electrical connections, these prior arrangements are generally complex and require a number of rather specialized components and may also prove difficult to assemble. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is a principal object of the present invention to provide a current transfer arrangement for a circuit interrupter that provides support for the contacts of the circuit interrupter and also provides current transfer between the contacts of the circuit interrupter and the external circuit terminal connection points directly through the end flanges/fittings thereof. 
     It is another object of the present invention to provide a current transfer arrangement for a circuit interrupter that utilizes a minimum number of simple components. 
     These and other objects of the present invention are efficiently achieved by the provision of a current transfer arrangement for a circuit interrupter that provides support for the contacts of the circuit interrupter and also provides current transfer between the contacts of the circuit interrupter and the external circuit terminal connection points directly through the end flanges/fittings thereof. The current transfer arrangement includes a first member assembled onto each of the circuit interrupter contacts and clamping members for securing the first member to the end flange. The end flanges include receiving grooves cooperating with the first member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The invention, both as to its organization and method of operation, together with further objects and advantages thereof, will best be understood by reference to the specification taken in conjunction with the accompanying drawing in which: 
     FIG. 1 is a perspective view of a circuit interrupter with parts cut away for clarity and illustrating the current transfer arrangement in accordance with the present invention; 
     FIG. 2 is an enlarged perspective view of the circuit interrupter of FIG. 1; 
     FIGS. 3 and 4 are respective partial front elevational views, partly in section, of bottom and top ends respectively of the circuit interrupter of FIG. 1; 
     FIG. 5 is an elevational view of a contact support/current transfer member of the current transfer arrangement of FIGS. 1-4; and 
     FIG. 6 is an elevational view of a retainer clip member of the current transfer arrangement of FIGS.  1 - 4 . 
    
    
     DETAILED DESCRIPTION 
     Referring now to FIGS. 1 and 2, a circuit interrupter  10  including the current transfer arrangement of the present invention provides electrical connection to power system circuit terminals at connection points  12 ,  14 , at the top and bottom respectively of the circuit interrupter. The connection points  12 ,  14  are provided on respective end flanges  16 ,  18  carried by a housing  20  of the circuit interrupter  10 . The end flanges  16 ,  18  are affixed to the housing  20  during fabrication thereof. The circuit interrupter includes upper and lower current carrying contact structures  22 ,  24  respectively that are relatively movable to open and close the circuit interrupter and thus make and break the electrical connection between the connection points  12 ,  14 . In the illustrative circuit interrupter  10  of FIG. 1, the lower contact structure  24  is movable via an operating rod  26  so as to define an open gap at  30  when the circuit interrupter  10  is open. Specifically, the lower contact structure  24  includes a movable contact member  41  that is movable via the operating rod  26  and a fixed contact member  42  that supports and transfers current at  43  to the movable contact member  41  that moves within the fixed contact member  42 . For example, a flexible contact arrangement is provided at  43  between the relatively movable contact members  41 ,  42 . 
     The current transfer arrangement of the present invention is utilized at  32 ,  34  to respectively connect an upper contact member  40  of the upper contact structure  22  to the circuit connection point  12  and the lower contact member  42  of the lower contact structure  24  to the circuit connection point  14 . 
     Specifically, and referring now additionally to FIG. 5, the current transfer arrangement includes a contact support/current transfer member  50  at  32  to support the upper contact structure  22  and transfer current through the upper contact member  40  to the upper flange  16 . Similarly, the current transfer arrangement includes a contact support/current transfer member  52  at  34  to support the lower contact structure  24  and transfer current through the lower contact member  42  to the lower flange  18 . The ends of the upper and lower contact members  40 ,  42  are threaded and cooperate with respective retaining nuts  60 ,  62  to secure the respective upper and lower contact support/current transfer members  50 ,  52  to the upper and lower contact members  40 ,  42  respectively. 
     With additional reference now to FIG. 6, retainer clip members  66  are provided along with fasteners at  68  to secure the upper and lower contact support/current transfer members  50 ,  52  to the respective end flanges  16 ,  18 , e.g. one retainer clip members  66  on either end of the members  50 ,  52 . The retainer clip members may also be characterized as clamp members. Specifically, the retainer clip members  66  at one end are received within a groove  65  of the end flanges  16 ,  18  and the fasteners  68  clamp the retainer clip members to the members  50 ,  52  that are received within grooves  70 ,  72  respectively in the respective end flanges  16 ,  18 . The retainer clip members  66  include an upwardly turned edge  67  (best seen in FIG. 6) that contacts the contact support/current transfer members  50 ,  52 . As will be apparent to those skilled in the art, the contact support/current transfer members  50 ,  52  and the end flanges  16 ,  18  are conductive or at least are conductive in the areas of interface in the current path. 
     In the illustrative circuit interrupter  10 , the lower end flange  18  and the lower contact arrangement  24  interface to an insulating support column  80  including an end flange  82 . Thus the central opening  19  of the lower end flange  18  communicates with and is connected to the end flange  82  of the insulating support column  80 , e.g. to provide a sealed environment therebetween. 
     At the upper end of the circuit interrupter  10 , an end plate  90  is secured to the upper end flange  16  via fasteners  92  and a seal element  94  disposed between the upper end flange  16  and the end plate  90 . Thus, it can be seen that the current transfer arrangement of the present invention is independent of the end closure of the housing  20  and is accomplished without involving passage through any gas-tight enclosure. Accordingly, the end plate  90  need not be conductive and can instead actually be insulating. 
     Considering now the assembling of the current transfer arrangement, at the upper end flange  16 , the member  50  is inserted on an angle through the central opening  17  and placed into the receiving groove  70  against a shoulder  71  of the groove  70 . Then, the retainer clip members  66  are positioned and fastened to clamp the member  50  against the retainer clip member  66 . Next, the contact member  40  is assembled to the member  50  via the retaining nut  60 , thus securing and supporting the upper contact structure  22  and also providing a current transfer path for the upper contact structure  22  to the terminal connection point  12  on the upper end flange  16  through the member  50 . 
     While there have been illustrated and described various embodiments of the present invention, it will be apparent that various changes and modifications will occur to those skilled in the art. Accordingly, it is intended in the appended claims to cover all such changes and modifications that fall within the true spirit and scope of the present invention.

Technology Category: 5