Abstract:
A meter socket assembly comprising a meter jaw assembly and an extended bus bar for contact with a meter blade of a watt hour meter. The meter jaw assembly further comprises a meter jaw and a jaw spring guide that are mounted together by a fastening device to the extended bus bar. The extended bus bar comprises a chamfered terminal end and cutout portion to easily accept the meter blade. The jaw spring guide overlies the meter jaw and applies a bias force inward to urge the contact face of the meter jaw toward the extended bus bar closing any insertion space and guaranteeing tight contact with the meter blade. A meter socket guide snaps on to the bus bar to maintain the alignment of meter jaw with watt-hour meter blade.

Description:
CROSS REFERENCE OF RELATED APPLICATION  
       [0001]     This application claims priority to and incorporates by reference herein in its entirety, pending U.S. Provisional Patent Application Ser. No. 60/717,802 (attorney docket no. 2005P16861US ) filed on Sep. 16, 2005. 
     
    
     FIELD OF INVENTION  
       [0002]     This invention relates to a meter socket assembly having a meter jaw for use with a watt-hour meter, and more particularly using a bus bar to directly contact a meter blade and limit heat rise generated by the connectors of the meter socket assembly.  
       BACKGROUND  
       [0003]     Socket type electrical watt-hour meters are used to measure and indicate the amount of electrical power consumption in a residence, industry or business. Typically, a socket type watt-hour meter plugs into a meter socket using a blade-like stab or meter blade connector located on the watt-hour meter. The meter socket itself is mounted inside a meter base or a panel. A meter socket commonly has a spring loaded receptacle-like jaw to receive and contact the watt-hour meter blade insertion. The meter jaw and spring provide enough force to press meter blade and conduct electricity while maintaining a certain current load and a heat rise. One disadvantage of the current meter socket is that the spring bias force may exceed the industry standard limit for the force required to insert and extract the watt-hour meter. Another disadvantage of the current meter socket is that the spring does not provide consistent pressure over time for a reliable connection between the meter jaw and watt-hour meter blade.  
         [0004]     The meter socket for a plug-in type watt-hour meter commonly uses “U” shaped one-piece or two piece jaw with return wrap receiving contacts. A disadvantage of the one-piece jaw, is that its shape limits the thickness of material used and more importantly, the one-piece jaw provides a long electrical current path by not directly contacting the meter blade and the bus bar. Similarly, there is a large amount of heat generated at the point of conduction in both the one piece and two piece jaws where such heat rise may cause meter malfunction if not properly dissipated.  
         [0005]     Another disadvantage of the known meter socket is the difficulty in aligning both the one piece and the two piece jaws in both the vertical and horizontal direction with the meter blade.  
         [0006]     Therefore there is a need for improvement in meter socket assemblies and in particular meter jaw assemblies.  
       SUMMARY OF INVENTION  
       [0007]     In accordance with this invention, a meter socket assembly for an electrical meter box comprising: a meter jaw assembly for securing and contacting a meter blade of a watt hour meter to an extended bus bar; and a fastening device for mounting the meter jaw assembly to the extended bus bar.  
         [0008]     In accordance with another aspect of this invention, a meter jaw assembly comprising: a meter jaw for contacting and securing a meter blade of a watt hour meter to an extended bus bar; and a spring jaw guide overlying the meter jaw.  
         [0009]     In accordance with a further aspect of this invention, a meter socket enclosure assembly comprising: a housing comprising a plurality of walls wherein a front wall includes an opening for mounting a watt hour meter; and an inner surface of a back wall of the housing containing a plurality of a meter socket assemblies for mounting the watt hour meter.  
         [0010]     In accordance with another aspect of this invention, a method to limit heat rise in a meter socket assembly of an electrical meter box comprising the steps of: providing an extended bus bar; providing a meter jaw assembly; and contacting a meter blade of a watt hour meter with an extended bus bar and a meter jaw assembly therebetween.  
         [0011]     It is a primary object of this invention to provide a meter jaw assembly with a direct contact bus bar.  
         [0012]     It is a further object of this invention to provide a meter jaw that will guarantee electrical connection even if there is misalignment between the meter jaw and the meter blade.  
         [0013]     It is further object of this invention to provide a jaw spring guide with side arm guides to hold a meter blade in position and help guide the meter blade vertically into the meter socket and maximize contact of the meter blade between the bus bar and meter jaw.  
         [0014]     It is a further object of this invention to provide a dual purpose bus bar, one that conducts electricity and also simultaneously transfers heat.  
         [0015]     It is a further object of this invention to provide a jaw spring guide that overlays a meter jaw in order to provide reinforcement and press the meter blade for full contact with both the meter jaw and the bus bar.  
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0016]      FIG. 1  is a side view of a meter socket assembly.  
         [0017]      FIG. 2  is a perspective view of a meter socket assembly.  
         [0018]      FIG. 3  is a side view of an alternate meter socket assembly.  
         [0019]      FIG. 4  is a perspective view of an alternate meter socket assembly.  
         [0020]      FIG. 5  is an exploded perspective view of a meter socket assembly.  
         [0021]      FIG. 6  is an exploded perspective view of an alternate embodiment of a meter socket assembly.  
         [0022]      FIG. 7  is a perspective view of a plurality of meter socket assemblies sitting in a basepan.  
         [0023]      FIG. 8  is a perspective view of a plurality an alternate type meter socket assemblies sitting in a basepan.  
         [0024]      FIG. 9  is a perspective view of a plurality of meter socket assemblies seated in a meter box enclosure housing. 
     
    
     DETAILED DESCRIPTION  
       [0025]     Referring to  FIG. 1 , meter socket assembly  10  includes an extended bus bar  20  and a meter jaw assembly  30 . Meter jaw assembly  30  comprises a meter jaw  40  and jaw spring guide  50  that overlies meter jaw  40 . The extended bus bar  20  features a chamfered receptacle terminal  60  (see  FIG. 2 ) that is coupled with meter jaw  40 . Chamfered receptacle terminal  60  creates a “V” shaped receptacle terminal with the upper portion of meter jaw  40  for easily inserting a meter blade (not shown) from a watt hour meter into the meter socket assembly  10 . The upper portion of the meter jaw  40  has an outward bend away from the chamfered receptacle terminal  60 . The middle portion of the meter jaw  40  has an outward joggle bend which then leans inward towards the extended bus bar  20 . The outward joggle bend shape helps meter jaw  40  fully contact the meter blade under load and also provides a bias spring force to press the meter blade to extended bus bar  20 . Extended bus bar  20  acts not only as a conductor to transmit electricity but also as a heat sink to quickly transfer away the heat generated during conduction. Jaw spring guide  50  provides the necessary bias spring force to reinforce and support meter jaw  40  so that meter jaw  40  and extended bus bar  20  hold the meter blade and allow extended bus bar  20  to maintain full contact with the meter blade during the watt hour meter&#39;s life time. The extended bus bar  20 , and meter jaw assembly  30  are mounted together with a fastening device  70 . In the preferred embodiment, the fastening device  70  is a screw. Others skilled in the art may select the fastening device  70  to be a clip, clamp, or a rivet element.  
         [0026]     Referring to  FIG. 2 , meter socket assembly  10  comprises at least one cut out portion  80  on the top side of extended bus bar  20 . The cut out portion  80  allows space for housing the meter feet of the watt-hour meter upon attachment to the meter socket assembly  10 . The cut out portion  80  will be sized to specification and industry standard. Jaw spring guide  50  includes at least one arm guide  90  which leads and locates the meter blade into full contact position once the watt-hour meter is attached to the meter socket assembly  10 . Arm guide  90  acts as a locating guide for locating and securing the meter blade of the watt hour meter. Arm guide  90  also acts an anti rotation mechanism for the meter blade while being inserted into the meter socket assembly  10 . Arm guide  90  integrally extends from the main body portion of jaw spring guide  50 . Others skilled in the art may select to not include an arm guide  90  for the jaw spring guide  50  and others skilled in the art may select to use more than one arm guide  90 .  
         [0027]     Referring to  FIG. 3 , meter socket assembly  10  includes a jaw spring guide  50  without an arm guide  90  for a ringless-type application. In this embodiment, the jaw spring guide  50  is designed to leave an insertion space between the upper portion of meter jaw  40  and extended bus bar  20  when meter jaw  40  is in an open (no meter blade inserted) state. The insertion space is designed to maintain insertion and extraction forces over the meter blade of approximately 100 lbs to ensure that the bias spring force stays within the industry standard limits for watt hour meter insertion and extraction once the meter blade is inserted and pressed against the meter jaw  40 . The insertion space between meter jaw  40  and extended bus bar  20  facilitates of insertion and extraction of watt-hour meter blades.  
         [0028]     Referring to  FIG. 4 , jaw spring guide  50  includes at least one locating feature  120  to locate the jaw spring guide  50  to the meter jaw  40  and extended bus bar  20 . Locating feature  120  will mate with shear guide  110  (show in  FIG. 5 ). Others skilled in the art may select not to use locating feature  120  and shear guide  110 . Others skilled in the art may also include at least one locating feature  120  in the meter jaw  40  (see  FIG. 5 ) and not include the at least one locating feature  120  in jaw spring guide  50 .  
         [0029]     Referring to  FIG. 5 , extended bus bar  20  includes at least one shear guide  110  to locate and mate with the locating feature  120  on meter jaw  40 . Meter jaw  40  includes at least one locating feature  120  to mate with the shear guide  110  and to locate and align both the extended bus bar  20  and the meter jaw  40  to one another. In this embodiment, meter jaw  40  is split cut in the middle to create (at least) two separated jaw fingers  130 . The separated jaw fingers  130  independently respond to the insertion of the meter blade and are able to absorb any slight misalignment of the meter blade along the insertion space between the meter jaw  40  and the extended bus bar  20 . Others skilled in the art may select to not split meter jaw  40  into separated jaw fingers  130 . Others skilled in the art may select to use a plurality separated jaw fingers  130 .  
         [0030]      FIG. 6  shows an alternative embodiment of the meter jaw assembly  10 . In this embodiment, meter jaw  40  shows no split down the middle to create separated jaw fingers  130 . Similarly,  FIG. 6  does not include arm guide  90  or locating features  120  on the jaw spring guide  50 .  
         [0031]      FIG. 7  shows a plurality of meter socket assemblies  100   a - d  mounted in a molded base pan  140 . The plurality of meter socket assemblies  100   a - d  are mounted to molded base pan  140  using attachment devices  150  and  160 . In the preferred embodiment, attachment devices  150  and  160  are a screw or rivet and bolt respectively. Attachment device  160  is threaded into the extended bus bar  20  and secures the extended bus bar  20  to molded base pan  140 . Those skilled in the art may use an insulating material to construct molded base pan  140  where insulating materials may include plastic, porcelain or ceramic. Attachment device  160  also includes the standard nut and flat washers which are prepared for additional bus connections. Secondary attachment device  170  is a square or ribbed neck bolt that prevents the bolt from turning or falling out when the nut is tightened. Attachment device  170  also uses standard nut with spring washer and flat washer that are prepared for additional bus connections. The ribs  180  on molded base pan  140  locate the plurality of meter socket assemblies  100   a - d  on assembly and as a result help guide the alignments for the meter blade insertion into the meter jaw  40  portions of the meter socket assemblies. The meter socket guide  210  (shown in  FIG. 8 ) also aligns the meter socket assemblies  100   a - d  on assembly. The meter socket guide  210  snaps between the meter socket assemblies  100   a - d  on the cut out portion  80  against the inside of the extended bus bar  20 . The meter socket guide  210  ensures the horizontal and vertical alignments of the respective meter jaw  40  of the meter socket assemblies  100   a - d  to provide precise fitting to watt-hour meter blades. Improved alignment of meter jaw  40  will allow easier insertion and extraction of the meter blade of the watt-hour meter and as a result improves the connection contact between meter jaw  40  and the meter blade. As a result of improved alignment, the connection contact will develop less heat under current load as the extended bus bar  20  will act as a heat sink and reduce heat from the connection contact. The molded base pan  140  has four mounting provisions to secure the plurality of meter socket assemblies  100   a - d  and two mounting provisions  220  (see  FIG. 8 ) to secure meter cover housing  190 .  
         [0032]      FIG. 8  shows a plurality of ringless type meter socket assemblies  100   a - d  mounted into molded base pan  140  as described in  FIG. 7 . In this embodiment the jaw spring guide  50  does not include arm guide  90 . With the mater socket guide  210 , the plurality of meter socket assemblies  100   a - d  are aligned horizontally and vertically.  
         [0033]     Referring to  FIG. 9 , meter cover housing  190  includes an opening  200  in the front wall of meter cover housing  190 . The meter cover  190  comprises a plurality of walls wherein an inner surface of back wall of meter cover housing  190  contains a plurality of meter socket assemblies  100 - a - d.  The meter socket assemblies  100   a - d  in its entirety is secured to the back wall of housing  190  through the four mounting provisions  220  on the molded base pan  140  (see  FIG. 8 ).  
         [0034]     While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the true spirit and scope of the present invention.