Abstract:
A socket assembly for a meter center including a plurality of meters is provided having a plate member and plural jaw assemblies. The plate member includes apertures for housing the jaw assemblies and structures associated with each of the apertures which function to both assist in initial alignment of the jaw assemblies during installation as well as to provide lateral support to, and maintain alignment of, the jaw assemblies after installation. The plate member further includes protrusions extending inwardly from the side walls of the apertures. The protrusions engage openings in side portions of the jaw assemblies.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates generally to electric power distribution systems and, more particularly, to socket assemblies for meter centers. The invention also relates to jaw assemblies for meter socket assemblies. 
         [0003]    2. Background Information 
         [0004]    Meter centers including a number of watt-hour meters are commonly used for metering electric power delivered to the tenant(s) of a residence (e.g., without limitation, a single family home; an apartment building) or commercial site (e.g., without limitation, an office complex). 
         [0005]    A typical electrical meter center  1  is illustrated in  FIG. 1 . The meter center  1  includes a cabinet  3 , having a plurality (only one is shown in  FIG. 1 ) of meter socket assemblies  5 . Each meter socket assembly  5  includes a plate member  7 , to which the various components of the socket assembly  5  are secured. Electrical power is supplied to the meter center  1  by feeder buses  9 . Feeder buses  9 , which typically consist of three phase buses and a neutral that are electrically connected to the utility lines (not shown), extend horizontally from the cabinet  3 , as shown in  FIG. 1 . A pair of vertical supply buses (not shown) is electrically connected to the feeder buses  9  within the cabinet  3 . Each meter socket assembly  5  mounts a meter  11  for each tenant circuit and electrically connects the meter  11  to the feeder buses  9  and the supply buses (not shown). Typically, the electrical connections between the meter  11  and socket assembly  5  are made by plug-in jaws  17 , which engage corresponding stabs  19  on the meter  11 . The use of the plug-in jaws  17  within the meter socket  5 , and corresponding stabs  19  on the back of the meter  11 , permits the meter  11  to be removed from the socket  5  when servicing the meter  11  is desired. 
         [0006]    In known designs, the connectors which incorporate the plug-in jaws were bolted to the plate member and to a corresponding one of the feeder buses or supply buses. This resulted in roughly  20  bolted connections in the electrical current path. Such connections required labor to complete and were subject to heating if they became loose. 
         [0007]    U.S. Pat. No. 5,951,324 discloses a socket assembly, which is intended to overcome the disadvantages of the multiple bolted connections. The socket assembly provides a plate member having a plurality of through apertures and double ended fastenerless meter jaws extending through the apertures with one end of each double ended meter jaw projecting from opposing first and second sides of the plate member. Assembly of the socket assembly involves pushing one end of each jaw into a corresponding aperture until a pair of locking tabs pass through the aperture and expand outwardly to lock the jaw in place. This eliminates current-carrying joints requiring fasteners, which can become loose between the meters and the supply and tenant buses. This also requires relatively less labor to install and remove meter sockets. 
         [0008]    Despite these improvements, there are drawbacks to the above proposal. One such drawback occurs when installing a meter having a plurality of stab contacts that must be engaged with the plural jaws on the socket assembly. Slight misalignment of the meter or variations in clamping force of the jaws can result in high insertion forces being encountered when inserting the stab contacts of the meter into the jaws of the socket assembly. Such high insertion forces can sometimes cause jaw spring clips to become misaligned or be forced through the socket base leading to improper contact engagement and damage to the meter and/or meter center and potentially complete installment failure. 
         [0009]    Accordingly, there is room for improvement in meter centers, socket assemblies for meter centers, and in jaw assemblies therefore. 
       SUMMARY OF THE INVENTION 
       [0010]    These needs and others are met by the embodiments of the invention, which provide members which engage, guide, and support a jaw assembly, to help retain jaw clips in desired positions within corresponding apertures of a meter socket. 
         [0011]    In accordance with one aspect of the invention, a jaw assembly is provided for a socket assembly of a meter center which includes at least one meter. The socket assembly includes a plate member having a first side, an opposing second side and an aperture passing therethrough. The jaw assembly comprises a meter jaw and at least one protrusion. The meter jaw has a first end, a second end disposed opposite and distal from the first end, a first side, a second side disposed opposite from the first side, a first opening disposed on the first side, a second opening disposed on the second side, and a body portion structured to be disposed within the aperture. The body portion further includes at least one opening. At least one protrusion is structured to extend inwardly from a periphery of the aperture in a manner which engages the meter jaw at or about at least one opening. 
         [0012]    The at least one protrusion may further include a second protrusion structured to extend inwardly from a periphery of the aperture in a manner which engages the meter jaw at or about another opening. The protrusions are preferably structured to maintain the meter jaw in a predetermined position with respect to the plate member. 
         [0013]    Another aspect of the invention is directed to a socket assembly for a meter center including at least one meter having stabs. The socket assembly comprises: a plate member, at least one guide member, and at least one jaw assembly. The plate member includes a first side, an opposing second side and at least one aperture therethrough. The guide member extends generally perpendicularly outward from the first side of the plate member at or about a corresponding one of the at least one aperture. The jaw assembly comprises: a meter jaw having a first end, a second end disposed opposite and distal from the first end, and a body portion having at least one opening. The body portion of the jaw is disposed within one of the at least one aperture. At least one protrusion is structured to extend inwardly from a periphery of the corresponding one of the at least one aperture, in order to engage the meter jaw at or about a corresponding one of the at least one opening. 
         [0014]    A further aspect of the invention is directed to a meter center having: a cabinet, a meter, and a socket assembly. The socket assembly, which is enclosed within a meter compartment of the cabinet, comprises: a plate member including a first side, an opposing second side and at least one aperture therethrough, at least one guide member extending generally perpendicularly outwardly from the first side of the plate member at or about a corresponding one of the at least one aperture and at least one jaw assembly. The jaw assembly comprises: a meter jaw having a first end, a second end disposed opposite and distal from the first end, and a body portion disposed within the corresponding one of the at least one aperture. The body portion includes at least one opening. At least one protrusion structured to extend inwardly from a periphery of the corresponding one of the at least one aperture, engages the meter jaw at or about a corresponding one of the at least one opening. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    A full understanding of the invention can be gained from the following description of the preferred embodiments when read in conjunction with the accompanying drawings in which: 
           [0016]      FIG. 1  is a partially exploded isometric view of a meter center. 
           [0017]      FIG. 2  is an isometric view of a meter socket plate in accordance with embodiments of the invention. 
           [0018]      FIG. 3  is a plan view of the meter socket plate of  FIG. 2 . 
           [0019]      FIG. 4  is a partially exploded view of the meter socket plate of  FIG. 2  with inserted meter jaws. 
           [0020]      FIG. 5  is a sectional view taken along line  5 - 5  of  FIG. 4 , with one meter jaw removed. 
           [0021]      FIG. 6  is an elevation view of one of the meter jaws of  FIG. 4 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    As employed herein, the term “number” shall mean one or an integer greater than one (i.e., a plurality). 
         [0023]      FIG. 4  shows a socket assembly  30 , for example, for use in place of the socket assembly  5  of  FIG. 1  for mounting a meter  11  in a cabinet  3  of a meter center  1 . Socket assembly  30  includes a socket plate  32  and a plurality of meter jaws  34 . Meter jaws  34 , best shown in  FIG. 6 , are preferably double ended to provide for electrical connection of the example meter  11  to feeder buses  9  inside the cabinet  3 . 
         [0024]    Socket plate  32  is preferably constructed of a rigid, electrically insulating material that may be readily formed by conventional molding processes commonly known in the art. Referring to  FIGS. 2-5 , socket plate  32  has a first surface  36 , an opposing second surface  38  and a general thickness t ( FIG. 5 ). Additionally, socket plate  32 , preferably, has two pairs  42 ,  44  of rectangular through apertures  40 , each pair being laterally aligned and the corresponding apertures in the two pairs being vertically aligned ( FIG. 3 ). Each of the rectangular apertures  40  is generally formed by a pair of opposing side walls  46  and two end walls  47 ,  48  ( FIG. 3 ). Side walls  46  and end walls  47 ,  48  extend between, and are generally perpendicular to, the first surface  36  and second surface  38  of the socket plate  32 . Opposing side walls  46  are generally oriented parallel to each other and perpendicular to end walls  47 ,  48 . 
         [0025]    Within each aperture  40 , an opposing pair of stops  50  project inwardly from opposing side walls  46 , one stop  50  per side wall  46 . Each stop  50  is generally centrally located on one of opposing side walls  46 . As shown in cross-section in  FIG. 5 , each stop  50  consists of a first face  52  inclined relative to opposing side walls  46  and a second face  54 . Preferably, second face  54  is oriented generally perpendicular to opposing side walls  46 . First face  52  provides a gradual transition from side wall  46  to an edge of second face  54 . Preferably, each stop  50  is located generally near a midpoint along each side wall  46 . As best shown in  FIG. 5 , stop  50  is preferably oriented in such a manner that second face  54  is located in relatively closer proximity to first surface  36  of socket plate  32  while the first face  52  extends from second face  54  toward second surface  38 . Although stops  50  are shown as being formed integrally with socket plate  32 , such stops could be separately formed and then suitably attached or coupled to socket plate  32 . 
         [0026]    Associated with each aperture  40 , is a guide member  56 , which generally extends away from first surface  36 . Guide member  56  may be formed separate from socket plate  32  and later affixed or may be integrally formed with socket plate  32 . As shown in  FIG. 2 , each guide member  56  has a support structure  57  and guide face  58 . The support structure  57  provides a rigid backing for guide face  58 , which is preferably substantially aligned with end wall  48  and oriented generally perpendicular to socket plate  32 . Guide face  58  may be integrally formed with end wall  48  so as to form a continuous surface (as shown in  FIG. 2 ) for guiding a meter jaw  34  ( FIG. 4 ) into the correct position during assembly as well as to provide lateral support for the meter jaw  34  when fully installed in aperture  40  as described below. 
         [0027]    Double ended meter jaws  34  are mounted in each of the apertures  40 , as shown in  FIG. 4 . As best shown in  FIG. 6 , each of the meter jaws  34  includes a pair of elongated flat members  60 . Flat members  60  each have a generally straight center section  62  and end sections  64  at each end which are bent back on but diverge from the center section  62 . Terminal sections  66  extend generally toward each other from the end sections  64 . The terminal sections  66  of the pair of elongated members  60  are clamped together in compliant confronting relationship by a pair of spring clips  68 . The end sections  64  form a guide which centers the meter jaw  34  on a stab contact  70  such as a supply bus stab contact which then wedges between the terminal sections  66 . 
         [0028]    Referring to the removed meter jaw  34  of  FIG. 4 , an opening  72 , is provided generally at a location midway between end sections  64  in the center section  62  of the two flat members  60 , which make up one of the meter jaws  34 . Thus, each assembled meter jaw  34  has a single, centrally located opening  72  on either side. Each opening  72  is of preferably, but not limited to, rectangular shape. The elongated flat members  60  of the meter jaws  34  have pairs of confronting tabs  74  bent out of the plane of the center section  62 . Preferably, tabs  74  are provided along each side edge of the elongated flat members  60 . Preferably, the spacing between the confronting tabs  74  is slightly less than, but in any event no greater than, the thickness, t, of the socket plate  32  ( FIG. 5 ). 
         [0029]    Socket assembly  30  is produced by locating meter jaws  34  in the apertures  40  of socket plate  32 . This is initially accomplished by inserting one end  64  of a meter jaw  34  into one of the apertures  40 . As shown in  FIG. 4 , end  64  of meter jaw  34  is inserted in one of the apertures  40  from the second surface  38  side of socket plate  32 . As the meter jaw  34  encounters the sloped first face  52  of the two stops  50 , the flat members  60  of the meter jaw  34  become compressed generally toward each other. When the meter jaw  34  has been inserted approximately half way into aperture  40 , the opening  72  encounters the corresponding stop  50 . Opening  70  is preferably sized to house therein the corresponding stop  50  and, thus, permit each of flat members  60  to return to generally their original separation. Once opening  70  has been moved in position to house stop  50 , second face  54  acts upon an edge of opening  70 , thus restricting movement of the meter jaw  34  in a direction opposite to that of insertion. In a preferred embodiment, guide face  58  is situated in relation to aperture  40  such that a portion of the meter jaw  34  travels along guide face  58  during installation and upon installation remains in contact with guide face  58 . In other words, guide face  58  serves to guide meter jaw  34  into its proper location during installation and also serves to maintain the meter jaw  34  in such desired alignment relative to the meter plate  32 . 
         [0030]    In addition to the interaction between stops  50  and openings  70 , a preferred embodiment of the meter socket assembly  30 , as shown in the figures, includes confronting tabs  74  on meter jaw  34 . Such tabs  74  nearest the inserted side of meter jaw  34 , compress inwardly from opposing side walls  46  upon insertion of the meter jaw  34  into the aperture  40 . After passing out the opposite side of the meter plate  32 , confronting tabs  74  spring outward so as to engage first surface  36  of the meter plate  32 . Similarly, the confronting tabs nearest the non-inserted end of the meter jaw  34 , having not been compressed, engage second surface  38 . The interaction between stops  50  and openings  72  as well as the engagement among the confronting tabs  74  and first and second surfaces  36 ,  38  serve to secure meter jaw  34  in meter plate  32  without need for any fastening members. The interaction between the pair of stops  50  and pair of openings  72  additionally provides the installed meter jaw  34  with greater resistance to high forces encountered during meter installation that would tend to force known jaw designs back through the meter plate. 
         [0031]    While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.