Abstract:
The invention provides an insulating meter jaw guide featuring a loop belt, a retaining fastener, a meter blade receiving slot, and a cavity housing. The insulating meter jaw guide may be positioned on a meter jaw of watt-hour meter socket, effectively covering the receiving end of a meter jaw or a meter jaw assembly, therefore, protecting the meter jaw from accidental contact by a meter cover or the like.

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. 60/968,202 (attorney docket no. 2007P18500US) filed on Aug. 27, 2007. 
     
    
     FIELD OF INVENTION 
       [0002]    This invention relates to a meter socket assembly having an insulating meter jaw guide for use with a watt-hour meter. 
       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 blade-like stabs or meter blade connectors 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 a sufficient clamping force on the meter blades and conduct electricity while maintaining a certain current load and a heat rise. 
         [0004]    Most utility companies in the United States require meter jaw guides to be installed on watt-hour meter sockets for locating the blades of watt-hour meters in the correct contact position. There are two types of material used for meter jaw guides: metal and thermal plastic. Metal meter jaw guides, are installed in pairs either on the outside or inside of line and load meter jaws. This provides a forceful guide to meter blades on effective contact position when a watt-hour meter is installed. 
         [0005]    At this time, thermal plastic meter guides are required by most utility companies for selective ring type meter socket assemblies. A thermal plastic meter jaw guide may cover a meter jaw and may be self-retaining on the jaw. A closing slot on the receiving side of a thermal plastic meter jaw guide limits a meter blade in the slot. Therefore, thermal plastic meter jaw guides will locate the watt-hour meter in an effective contact position. Thermal plastic meter jaw guides also insulate line meter jaws from non-intentional contact. This will serve as an additional protective feature for electricians who are working with watt-hour meters without disconnecting electrical power. 
         [0006]    One disadvantage of using thermal plastic is that the physical properties of thermal plastic show less strength and softer composition at high temperature. As a result, the thermal plastic meter jaw guide may break if excessive force is needed to insert a watt-hour meter. Therefore, some utility companies reject thermal plastic meter jaw guides and prefer metal meter jaw guides. 
         [0007]    Another disadvantage commonly faced relates to a ring type meter covers having a reinforced return flange on the top end. The edge of the return flange, if lower than the side of supporting walls of the meter cover, may contact the bearings of line meter jaw or meter jaws during removal of the meter cover. A contact between the meter cover and “hot” meter jaw or meter jaws may cause electrical shock and/or short circuit, which may result in personal or property damage. 
         [0008]    Therefore there is a need for improvement to provide a reliable meter jaw guide for locating meter blades in the meter jaw and to provide protection from contact with a meter jaw. 
       SUMMARY OF INVENTION 
       [0009]    In accordance with one aspect of this invention, the method to insulate a meter jaw assembly for an electric meter box, comprising the steps of: providing the meter jaw assembly comprising a metal meter jaw guide in combination with a meter jaw for securing insertion of a meter blade of a watt hour meter; and providing an insulating meter jaw guide wherein the insulating meter jaw guide overlays the meter jaw assembly. 
         [0010]    In accordance with another aspect of this invention, a meter socket device for an electrical meter box comprising: a meter jaw assembly for securing and contacting a meter blade of a watt hour; meter socket base for mounting the meter jaw assembly; and an insulating meter jaw guide overlaying the meter jaw assembly. 
         [0011]    In accordance with another aspect of this invention, a meter jaw assembly for an electric meter box comprising: a metal meter jaw guide in combination with a meter jaw for securing insertion of a meter blade of a watt hour meter; and an insulating meter jaw guide overlaying the meter jaw in combination with the metal meter jaw guide. 
         [0012]    It is an object of this invention to protect meter jaws and metal meter jaw guides from accidental contact during operating a watt-hour meter or removing, installing, or replacing a meter cover. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0013]      FIG. 1 . is a perspective view of a meter socket device. 
           [0014]      FIG. 2 . is a perspective view of a meter socket block assembly including an insulating meter jaw guide. 
           [0015]      FIG. 3   a ) is a perspective view of the insulating meter jaw guide. 
           [0016]      FIG. 3   b ) is a perspective view of the meter jaw with a metal jaw guide. 
           [0017]      FIG. 4   a ) is an enlarged view of varying angle of the insulating meter jaw guide. 
           [0018]      FIG. 4   b ) is an enlarged view of the insulating meter jaw guide turned upside down. 
           [0019]      FIG. 4   c ) is an enlarged and varying view of a combination of a meter jaw and a metal meter jaw guide. 
       
    
    
     DESCRIPTION  
       [0020]      FIG. 1  shows an electrical meter socket device  10 . The meter socket device  10  includes an enclosure  100  and a watt-hour meter  200 . The watt hour meter  200  is shown in phantom line to reveal the meter socket assemblies  500  (right meter socket assembly  300  and left meter socket assembly  400 ) located inside. In residential applications, most meter socket devices  10  may contain a 4 or 5-meter jaw sockets for connecting 2 pair of parallel meter blades (not shown but well known to those skilled in the art) from the watt-hour meter  200 . Each pair of meter blades from the watt-hour meter  200  connects to one phase of utility power for consumption through a meter socket device  10 . The consumption of electrical power is measured when the currents flow in from a line meter jaw assembly  600  (also shown in  FIG. 2 ) to line meter blades then through the watt hour meter  200  then flow back out from load meter blades to load meter jaw assembly  700  (also shown in  FIG. 2 ). The enclosure  100  provides protection to all electrical connections and links the utility electrical power lines to the lines connected to consumer distribution panels. When the watt-hour meter  200  is installed and sealed, all internal connectors are enclosed and protected by the watt-hour meter  200  and the enclosure  100 . For ease of reference, line meter jaw assembly  600  and load meter jaw assembly  700  will collectively be called meter jaw assemblies  800 . 
         [0021]      FIG. 2  shows the right meter socket assembly  300 . The line lug  900  connects utility electrical power line to receive electrical power. The electrical power is transferred to line meter jaw assembly  600 . Passing through a watt-hour meter, the electrical power is delivered to the load meter jaw assembly  700  then to the load lug  950  for customer consumption. The line and load lugs  900 / 950  and the meter jaw assemblies  800  are all installed on a plastic base  1000 , which provides mounting and support for the conductors and provides insulation between them. To receive a watt-hour meter  200 , the meter jaw assemblies  800  of the right meter socket assembly  300  are installed on top of the plastic base  1000 , reaching out above any other components. Once the utility line is connected and utility provides electricity, the line lug  900  and line meter jaw assembly  600  remain connected to the electrical power source. Even though the watt-hour meter  200  is removed, the electrical power on load meter jaw  700  and load lug  950  is interrupted (disconnected), but the electrical power on line lug  900  remains connected and the line lug  900  and line meter jaw assembly  600  remain energized. Therefore, an insulating meter jaw guide  1200  is strongly recommended to safe guard the line meter jaw assembly  600  from non-intentional contact. 
         [0022]    Line meter jaw assembly  600  comprises a line meter jaw  650 , a metal meter jaw guide  1100  and an insulating meter jaw guide  1200 . Load meter jaw assembly  700  comprises a load meter jaw  750  and a metal meter jaw guide  1100 . The line/load meter jaws  650  and  750  have return fold leads  3100 / 3100 ′ (shown in  FIG. 4c ) to receive and clamp watt-hour meter blades. The meter jaw assemblies  800  align to match the position of the two meter blades of the same phase under a watt-hour meter  200 . The metal meter jaw guide  1100  has a meter blade guide finger  2700  (as shown in  FIG. 3   b ). The meter jaw guides  1100  in meter jaw assemblies  800  couple together with their meter blade guide fingers  2700 . The meter blade guide fingers  2700  may be fixed either externally or internally to the meter jaw assemblies  800 , allowing the meter blade guide fingers  2700  to bias meter blades in an opposite direction. This forces the meter blades of a watt-hour meter  200  to be inserted in the line/load meter jaws  650  and  750  with proper contact. 
         [0023]      FIG. 3   a ) shows an enlarged view of an insulating meter guide  1200  ready for installation.  FIG. 3   b ) shows an enlarged view of line meter jaw assembly  600  where the line meter jaw  650  and the metal meter jaw guide  1100  are assembled together. The insulating meter jaw guide  1200  includes a rectangle cavity housing overlaying the meter jaw  650  and the metal meter jaw guide  1100  by covering top portion of side walls  1400  and top return surface  1500  and  1500 ′. Closing end  1700  of the insulating meter jaw guide  1200  has opening slot  1600  to receive meter blade insertion while closing end  1700  covers the top return surface  1500  and  1500 ′ of the meter jaw  650 . Extended bumper  1800  on the insulating meter jaw guide  1200  prevents unexpected objects from contacting the meter jaw  650 . The loop belt  1900  on the insulating meter jaw guide  1200  wraps around and hooks between the meter blade guide finger  2700  and its receiving lead  2000 . The opened portion of the loop belt  1900  relieves the outward biased receiving lead  2000 . The side walls  2100  of opened portion of the loop belt  1900  and extended top walls  2200  surrounds the top edge  2300  of the metal meter jaw guide  650  for protection. On the other side of the insulating meter jaw guide  1200 , an extended leg  2400  includes a “U” shaped retaining fastener  2500 . The “U” shaped retaining fastener  2500  acts as snap stab and locks to the end of the return connection walls  3100  and  3100 ′ (shown in  FIG. 4   c ) of the meter jaw  650 . The side surfaces  2600  of the “U” shaped retaining fastener  2500  are wide enough to fix the end corner of the return connection walls  3100  and  3100 ′ and small enough to fit between the spring fingers  2800  and  2800 ′ (shown in  FIG. 4   c ) of the metal meter jaw guide  1100 . 
         [0024]      FIGS. 4   a ) and  4   b ) show an enlarged and varying view of the insulating meter guide  1200 .  FIG. 4   b ) focuses on the insulating meter guide  1200  turned upside down. The ribs  2900  inside the side walls  3000  provide a tighter fit to the side walls  1400  and  1400 ′ shown in  FIG. 4   c ) of the meter jaw assembly  600 . 
         [0025]    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.