Abstract:
A watthour socket adapter base carries jaw blades for receiving blade terminals on a meter device and connectable to meter socket jaw contacts. Latch member carrier by drive members on an annular ring engage a socket cover to fixedly mount the latch base to the socket cover. Barriers surround each drive member to electrically insulate the drive members from the jaw contacts. Apertures in the base are surrounded by strain relief and lock fingers to accommodate the passage of conductors throgh the base. Conformable discontinuities are formed in the annual ring of the base to conform to different diameter shells attachable to the base. In another aspect, the latch members are pivotally mounted on an outer surface of the base and movable between latching and unlatching positions by rotation of a fastener extendible through the shell and the base and engaged with the latch members.

Description:
BACKGROUND 
     The present invention relates, in general, to watthour meters and meter sockets and, more specifically, to watthour socket adapters or extender adapters for mounting, recording and other instrumentation equipment on ringless style watthour meter sockets. 
     In the electric utility industry, plug-in, socket-type watthour meters are commonly employed to measure electric power consumption at a residential or commercial building establishment. A socket is mounted on a wall of the residence or building and contains terminals which are connected to electric line and electric load conductors. The terminals are also connected to internal conductors within the socket which extend to jaw contacts positioned to receive the blade terminals of a plug-on watthour meter to complete an electric circuit through the watthour meter between the line and load terminals and the conductors. 
     One type of meter socket has a ring-type cover which includes an outwardly projecting, annular mounting flange surrounding an opening in the cover through which the blade terminals of a watthour meter extend. The mounting flange is sized to mate with a complementary formed mounting flange on the base of the watthour meter. The two mating mounting flanges are held together by a sealing ring. 
     Another type of meter socket has a ringless style cover which has only a slightly raised boss surrounding an aperture in the cover. The meter and/or socket adapter is connected to the jaw contacts in the socket and has an end portion which extends through the aperture. 
     While a socket adapter can be easily attached to either meter socket cover style for receving a plug-in watthour meter, it is necessary sometimes to connect load survey equipment or recording equipment to the meter socket for various study and reporting surveys. Since such equipment is frequently contained in a housing which is too large to pass through the aperture in the socket cover or to be connected to the mounting flange in a ring style cover for connection to the socket jaw contacts, latch base socket adapters have been devises which include the standard jaw blades for receiving blade terminals in the survey equipment in a plug-in connection, with ends of the jaw blades passing through the latch base for plug-in connection to the socket jaw contacts. Such a latch base includes lock members which are engagable exteriorly of the socket cover to move latch fingers behind the latch cover to securely mount the latch base to the socket cover on a meter socket. 
     One prior art approach to providing a latch base socket extender adapter is shown in FIGS. 1A and 1B. This extender adapter is modeled after Ekstrom Industries, Inc., 38 series extender adapter and is formed of a two-part base and shell. The base, shown in FIG. 1A, has a circular cross section formed of a bottom wall, a radially outward extending mounting flange and a short length side wall. A plurality of apertures extend through raised bosses on the base wall and the base wall for receiving the blade end of jaw blades shown in FIG. 1B mounted through the shell and base for interconnection with the socket jaw contacts. 
     A plurality of mounting screw bosses are disposed internally of an annular ring concentric within the mounting flange and extending from the base wall. The bosses receive mounting screws to which an L-shaped, steel latch flange is attached. The bosses guide movement of the L-shaped latch flange as the screws are threaded in and out relative to the base. Such movement of the screws bidirectionally extends a lower leg of the latch flange mounted around each screw underneath the adjoining raised boss on the ringless socket cover to fixedly attach the base to the metal surrounding the opening in the cover. Since the heads of the screws are disposed externally of the side wall of the base as part of a cast metal ring mounted around the side wall of the base on one side of the mounting flange, the base end of the extender adapter can be mounted through the opening in the ringless socket cover after the cover has been installed on the meter socket. 
     Bore are cross drilled in the screw heads for receiving a meter seal which extends through an adjacent aperture in an ear formed on the metal ring after the screws have been threaded to their fully latched position. 
     The shell has a bottom wall and a side wall extending therefrom to an external mounting flange mateable with complimentary mounting flanges on load survey recording equipment or other metering instrumentation. Bosses in the shell support the jaw blades which pass through the bottom wall of the shell and the bottom wall of the base for connection at a blade end with the socket jaw contacts. The shell is fixedly attached to the base by screws which extend through apertures in the bottom wall of the shell into bores formed in mounting bosses in the base as shown in FIGS. 1A and 1B. 
     While such an extender adapter proves an effective means to install load survey recorders and other types of meter recording equipment or instrumentation on ringless style sockets, it is difficult to reliably seal the shell to the base which can lead to corrosion. Further, as shown in FIG. 1A, the interior ends of the screws are disposed in close proximity to the jaw blades extending between the bottom wall of the shell and the bottom wall of the base. This creates an arcing potential. Further, there is no capability for accommodating a watthour meter having an external accessory box or an external wire which needs to be routed through the socket adapter into the meter socket. 
     A different approach to a latch base type socket adapter is one sold by Marwell Corporation as Model No. E/Z 1800. In this socket extender adapter, the cast ring and screw head seal ears are integrally molded as part of the short side wall of the base which has a double thickness compared to the latch base socket extender adapter shown in FIGS. 1A and 1B. The inside pocket surrounding the inner end of each screw has one higher length wall at a radially inner end. However, the other two side walls remain short exposing the metal screw and the latch flange to arcing potential from adjacent jaw blades. 
     This design also presents difficulties inadequately sealing the shell to the base which can lead to corrosion. Further, the close proximity of the screw seal ears and the screw heads prevents the use of the popular Plastic Padlock Seal sold by E.J. Brooks Company, Livingston, N.J. 
     In both latch base adapters shown in FIGS. 1A,  1 B and  2 , the mounting screws are retained in the base by means of roll pins inserted through holes drilled in the enlarged bosses on the ring and into an annular recess formed in each screw. Such roll pin captures a screw relative to the ring while allowing the screw to rotate to move the attached latch member between the latched and unlatched positions. However, the drilling of the holes in the ring for each roll pin and the mounting of the roll pins in the holes requires additional assembly steps and time which increase the cost of these prior latch base adapters. 
     Another deficiency of the prior art latch base adapters shown in FIGS. 1A,  1 B and  2  is that only, wire tamper indicating seals can be mounted through the screw heads and the ears for flanges on the ring to indicate that screws are in their final, latch engaged position without tampering or attempts to remove the latch base from the socket cover. 
     Thus, it would be desirable to provide a latch base watthour meter socket extender adapter which overcomes the problems associated with previously devised latch base socket extender adapters. It would also be desirable to provide a latch base socket extender adapter which has the mounting ring, base wall screws and latches formed as a one-piece assembly, which can accommodate different diameter shells so as to eliminate the need for a shell to base seal, which fully encapsulates the interior end of the mounting screws for high arc resistance, which accommodates seals for the mounting screws, which can easily accommodate a conventional watthour meter sealing ring, which has a frangible mounting flange to adapt to ring style socket covers with varying opening mounting rings, which has gas vent and external wire passage, strain relief apertures and, finally, or which has optional top and bottom swing latches to provide an internal mounting connection to a meter socket cover. It would also be desirable to provide a latch base socket extender adapter which can receive a meter sealing ring which encompasses the drive member or screw heads to prevent any unauthorized access to the mounting screws in an attempt to unauthorizedly remove the latch base from the socket cover. It would also be desirable to provide a latch base socket extender adapter which has a reduced manufacturing cost as compared to prior art latch base adapters by eliminating the need for the prior art use of roll pins and holes in the ring. 
     Watthour meter socket adapters in general which are formed of a base and a shell, either integrally formed or separately attachable and which are mountable in a watthour meter socket through an aperture in a ringless style meter socket cover or to a mounting flange on a ring style cover have some of the same deficiencies noted above for latch base adapters. 
     It is difficult to easily pass flexible conductors or wires from the watthour meter though the adapter to equipment mounted in the meter socket. In addition, it is still necessary to accommodate a sealed fit between the separate base and shell. Further, ring style socket adapters and ringless style socket adapter still require two different adapters. 
     Thus, it would be desirable to provide a watthour meter socket adapter which overcomes these deficiencies. 
     SUMMARY 
     The present invention is watthour meter socket adapter. In one aspect of the invention, the socket adapter has a latch base which is mountable through the aperture in a meter socket cover to enable metering devices, such as load survey recorders, etc., to be temporarily connected to the jaw contacts in the meter socket. 
     The inventive latch base adapter includes a housing having a base with the flange extending radially outward from the base. An annular ring extends from the base and the flange and carries a mounting flange at an outer end. A plurality of drive members, such as screw fasteners, are radially extendable thorough the ring. A latch is coupled to each drive member for movement into engagement with the meter socket cover adjacent to an aperture in the cover. 
     In one aspect of the invention, conformable means in the form of at least one annular discontinuity, is carried on the annular ring for adjusting the engagement of the ring with a shell attachable to the housing. In another aspect, trap members are carried in the housing for axially capturing the drive members to enable the drive members to rotate without axial movement relative to the annular ring. The trap members include a wall extending from the housing and having at least one edge angled with respect to the longitudinal axis of the drive member. The edge of the wall cooperates with a recess carried on each drive member to prevent axial displacement of the drive member during rotation of the drive member. 
     In another aspect of the invention, each latch member has at least one projection which engages the ring on full outward positioning of the latch and causes a lever action to be exerted on the latch member to drive the other leg of the latch member into tight engagement with the cover to mount the latch base of the adapter to the socket cover. 
     In another aspect of the invention, at least one seal member is carried on each drive member for environmentally sealing each drive member to the annular ring. The seal member may be mounted in an annular recess carried on each drive member. 
     In another aspect of the invention, the flange extending from the base of the housing includes frangible means for enabling an outer ring portion of the flange to be separated from the remainder of the flange to conform a single latch base design for use on both ring style and ringless style meter socket covers. 
     In another aspect of the invention, barrier means are carried in the housing for electrically insulating each drive member from adjacent electrically conductive elements in the housing. The barrier means encompass substantially all sides of the drive member projecting interiorly of the annular ring. The barrier means may be combined with the trap members so that the trap members are carried on the barrier means to provide both axial capturing and insulating features. 
     In another aspect of the invention, at least one flange is carried on and extends radially outward from the annular ring on the housing. An aperture is formed in the flange and is alignable with an aperture formed in the head portion of the drive member exteriorly of the annular ring. A seal indicator, such as a wire lead seal or meter padlock seal is extendable thought the aligned apertures to indicate a sealed position of the drive member. In another aspect, one edge of the flange is spaced from the flange in the housing and defines a recess for receiving one portion of a sealing ring mountable about the flange and the drive member. 
     In another aspect of the invention, a plurality of ribs are formed on the annular ring. The ribs have a tapering outer edge to center the shell with respect to the housing. This eliminates the need for a silicone seal used in the prior art to seal the shell to the base. 
     In another aspect of the invention, at least one and preferably a plurality of apertures are formed through the base of the housing. A plurality of resilient fingers are formed in the base and extend from the aperture. Each finger has a free end located at the aperture to form a strain relief for an electrical conductor passing through the aperture into the meter socket. The apex edge of the free end of each finger is bendable from the plane of the base to lockingly engage the conductor extending through the aperture and to prevent the conductor from easy withdrawal through the aperture. 
     In another aspect of the invention, a plurality of latch members are carried on the base of the housing and movable between a first retracted position allowing insertion of the housing through an aperture in a socket cover, and a second extended position to fixedly latch the housing to the cover. The fastener is extendable through the housing and one latch member. The latch member is mounted on the fastener so as to be rotatable with the fastener. In one aspect, the fastener is the same fastener used to mount the shell to the mounting flange of the housing. 
     The electrical power service apparatus in the form of a meter socket adapter with a latch base overcomes many of the difficulties encountered with previous watthour meter socket adapter latch base designs. 
     The conformable wall of the annular ring allows the ring on the base to accommodate different diameter shells for easy manufacturing and versatility in application of the inventive latch base. 
     In another aspect, the barrier means completely electrically insulates the conductive portions of the latch drive members, typically the screw fasteners, from adjacent electrically conductive jaw contacts or jaw blades in the housing to provide a high arc resistance. 
     The unique provision of openings in the latch base with resilient edges provides strain relief for the passage of conductors through the latch base to the meter socket. 
     The arrangement of the drive member head and the adjacent flange on the annular ring formed as one piece with the latch base enables the use of the inventive latch base with both ring style and ringless style meter socket covers. In addition, conventional watthour meter socket sealing rings may be uniquely mounted over the head and the flanges of each latch drive members to encompass the latch drive members in the latch engagement position and prevent access to the drive members during an unauthorized attempt to remove the latch base from the socket cover. 
     In another aspect of the invention, the base wall mounting end is conformable in diameter to mate with different diameter shells so as to eliminate the need for a separate, low reliability, silicone shell to base environmental seal. 
     In another aspect, the ear or flanges on the base ring and the slots through the latch drive member heads are configured to accommodate any conventional meter seal device, such as a plastic pad lock seal or wire lead seal. 
     In another aspect, optional latch members used by themselves or in combination with the aforementioned latch drive members are mountable on the rear outer surface of the latch base and are pivotal between latching and unlatching positions to releasably affix the latch base to a meter socket cover. Preferably, the fasteners used to attach the shell to the base extend through the base and are engagable with the latch members for moving the latch members between the latched and unlatched positions. 
     In another aspect of the invention, the socket adapter includes a base and a shell which are joined together by fasteners. The conformable means described above carried on the annular ring of the base for adjustably accommodating the sealed engagement of the base with the shell can be advantageously employed for many other watthour meter socket adapters, not just latch base socket adapters. 
     In another aspect, the frangible rim described above may also be employed in other types of watthour meter socket adapters to enable an outer portion of the mounting flange to be separated from the remainder of the flange to conform the watthour meter socket adapter base for use on both ring style and ringless style meter socket covers. 
     In another aspect, at least one and preferably a plurality of apertures are formed in the base of the socket adapter. A plurality of resilient fingers are formed in the base and extend from each aperture. Each finger has a free end located at the aperture to form a strain relief for an electrical conductor passing through the aperture into the interior of the meter socket. The apex edge of the free end of each finger is bendable from the plane of the base to lockingly engage the conductor extending through the aperture to prevent the conductor from easy withdrawal from the aperture. 
     In yet another aspect, a plurality of latch members carried on one surface of the base, which are described above, may be employed for mounting a conventional watthour meter socket adapter base to a meter socket cover. The latch members are movable between a first retracted position allowing insertion of the socket adapter housing through an aperture in the socket cover to a second extended position to latch the socket adapter base to the socket cover. The fastener extendible through the shell and base of the housing to connect the shell and base together also receives one latch member to enable the latch member to be rotatable with rotation of the fastener. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The various features, advantages and other uses of the present invention will become more apparent by referring to the following detailed description and drawing in which: 
     FIG. 1A is a front elevational view of a latch base used in a poor art latch base watthour meter socket extender; 
     FIG. 1B is a front perspective view of the prior art latch base in FIG. 1A depicted connected to a shell and mounted in a ringless style watthour meter socket cover; 
     FIG. 2 is a front elevational view of another prior art latch base watthour meter socket extender; 
     FIG. 3 is perspective view of a latch base watthour meter socket extender adapter according to one aspect of the present invention; 
     FIG. 4 is an enlarged perspective view of the base of the latch base socket extender adapter shown in FIG. 3; 
     FIG. 5 is a front elevational view of the base shown in FIG. 4; 
     FIG. 6 is an enlarged, cross-sectional view through one of the latch drive members and the base shown in FIGS. 4 and 5; 
     FIG. 7 is a plan elevational view, partly in cross section, of the latch drive member shown in FIG. 6; 
     FIG. 8 is a partial perspective view showing the mounting of the latch base and a sealing ring on a ringless style meter socket cover, 
     FIG. 9 is an enlarged, cross-sectional view showing the latch drive member and a sealing ring on a ring style meter socket cover, 
     FIG. 10 is a perspective view of the rear surface of the latch base and depicting optional latch members shown in FIGS. 4 and 5; 
     FIG. 11 is an enlarged, perspective view of the optional latch finger shown in FIG. 10; 
     FIG. 12 is a side cross-sectional view showing the mounting arrangement between the latch finger shown in FIG. 11, and the latch base on a ring style meter socket cover; 
     FIG. 13 is a side cross-sectional view showing the optional latch finger depicted in FIG. 11 with the latch base mounted on a ring style meter socket cover, 
     FIG. 14 is an enlarged plan view of the drive member, seal flange and sealing ring shown in FIG. 4; and 
     FIG. 15 is a partial cross sectional view through one of the base apertures showing the strain relief fingers relative to a pass through conductor. 
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawing, and to FIGS. 3-10 in particular, there is depicted a watthour meter socket extender adapter  20  hereafter referred to simply as the “adapter  20 .” The adapter  20  includes a housing  22  formed of a base  24  and a shell  26 . 
     The shell  26  is conventionally constructed of an electrically insulated material such as polycarbonate, and has a bottom wall  30  and a side wall  32  extending therefrom. The bottom wall  30  and the side wall  32  may be integrally constructed as a one-piece molded member. The side wail  32  terminates in a radially outward extending mounting flange  34  surrounding an open outer end  36 . 
     A pair of surge ground conductors  40  and  42  have an end portion projecting over and seated on the mounting flange  34  and a leg portion extending inward along the sidewall  32  to an internal connection on the bottom wall  30  by one of the mounting screws used to attach the bottom wall  30  of the shell  26  to the base  24 . 
     A plurality of bosses  44  are integrally formed on the bottom wall  30  and receive jaw blades, not shown. 
     The base  24  is in one aspect of the present invention shown in greater detail in FIGS. 4-10 formed as a latch base  24 . The latch base  24  may also be formed as a one-piece, molded member of a suitable electrically insulating material, such as polycarbonate. The base  24  includes a bottom wall  50  and a stepped side wall denoted generally by reference number  52  which projects from an inner band  54  at the bottom wall  50  to stepped inner and outer annular ends  56  and  58 , respectively. 
     The stepped ends  56  and  58  form a seat for receiving an edge of the bottom wall  30  of the shell  26 . A plurality of apertures  58  are formed in the bottom wall  50  for receiving one end of the jaw blades, not shown, extending from the bottom wall  30  of the shell  26 . 
     A plurality of mounting bosses  60  are circunferentially spaced about the bottom wall  50  and project from an enlarged diameter end  62  adjacent to the bottom wall  50  to an outer end substantially coplanar with the inner end  56  of the side wall  52 . A bore  64  projects through each mounting boss  60  and may be threaded for receiving a threaded fastener, such as a screw, extending through one of the apertures in the bottom wall  30  of the shell  26  to fixedly secure the shell  26  to the base  24 . 
     A plurality of mounting feet  70 , such as four, for example, project from the outer surface of the bottom wall  50  of the base  24 . One mounting foot  70  is disposed adjacent to the blade end of one jaw blade extending through one of the apertures  58  in the bottom wall  50 . 
     A mounting flange  72  projects radially outward from the side wall  52  in the vicinity of the inner annular band  74 . Frangible means  73  are optionally formed in the flange  72  in the form of one or more score lines to enable another edge portion of the flange  72  to be separated from the remainder of the flange  72 . This enables a single diameter flange  72  to be molded; yet the flange  72  can be varied in diameter to adapt the base  24  for mounting on ring style or ringless style meter socket covers. 
     In one aspect of the present invention, the latch base  24  is provided with a conformable diameter means which includes a variable diameter sidewall  52  formed by a discontinuous or an irregular accordion shaped portion  76 . The portion  76  is formed of at least one end, preferably a plurality of circunferentially extending sawtooth shaped ribs defined by alternating outwardly extending projections  78  and recesses  80 . 
     The portion  76  serves two functions. First, the portion  76  serves as a weep hole at the bottom of the latch base  24  to allow any liquid which may have inadvertently entered the latch base  24  to flow out from the latch base  24 . Secondly, the accordion portion  76  provides a deformable side wall  52  to enable the diameter the side wall  52  to expand when engaged in the bottom wall  30  of the shell  26  to accommodate different diameter shell bases  30 . 
     As clearly shown in FIGS. 4 and 5, at least one and preferably a plurality of apertures  82 , with four apertures  82  being shown by way of example only, are formed in the bottom wall  50 . Most of the apertures  82  are formed in the bottom wall  50  of the base  24  at spaced locations on the bottom wall  50 . By example only, one of the apertures  84  is formed in an enlarged boss  86  adjacent one of the mounting bosses  60 . 
     The apertures  82  and  84  may take any shape, with the illustrated circular shape being used for one or more conductors which can pass freely through the apertures  82  and  84 . For larger diameter conductors, having a outer diameter larger than the diameter of the apertures  82  and  84 , a plurality of score lines or perforations extending in a star shape, by example only, are formed in the solid portion of the base  60  surrounding and extending radially from each aperture  82  and  84  typically around the entire 360° circumference of each aperture  82  or  84 . The score lines or perforations  83  are formed at a predetermined depth to allow a large diameter conductor to be forced through the aperture and the surrounding solid portion of the base  50  with sufficient force to separate the score lines  83  and to form the illustrated fingers between the separated slits in the base  50  allowing the conductor to pass freely through the now enlarged cross section area surrounding the aperture  82  or  84 . 
     The intervening, flexible solid portions when separated from the bottom wall  50  surrounding the aperture  82  or  84  serve as a strain relief for larger diameter conductors. The solid portions or fingers between the slits also prevent pullout of a conductor extending therethrough. The solid portions will be bent outward from the plane of the bottom wall  50  to an angle from the bottom wall  50  as shown in FIG. 15 to act as latch fingers having rigidity to resist movement of the conductor in a direction opposite from the insertion direction via the engagement of the ends of each solid portion with the outer surface of the conductor. This strain relief and lock function is shown in FIG.  15 . 
     As shown in FIGS. 4-9, at least one and preferably a plurality of pockets or receptacles  90 , with three pockets  90  being shown by way of example only, are carried in the latch base  24 , preferably as an integral, one-piece, molded part of the base  24 . The pockets  90  are circunferentially spaced, equidistantly about the sidewall  52  and project radially inward from the sidewall  52 . Each pocket  90  has a generally U-shape formed of opposed sidewalls  92  and  94  extending radially inward from the sidewall  52  and an end wall  96  extending between the sidewalls  92  and  94  and radially spaced from the sidewall  52 . 
     An important advantage accorded by the pockets  90  is that the sidewals  92 ,  94  and the end wall  96  project substantially the full height of the sidewall  52  of the base  24  from the bottom wall  50  to the outer extent of the sidewall  52 . This provides full arc protection between all sides of the conductive latch finger of the lock means described hereafter which is disposed within each pocket  90  and the adjacent electrically conductive jaw blades. 
     As shown in FIGS. 6 and 7, one, and preferably a plurality (i.e., three) apertures or slots  98  is formed in the bottom wall  50  adjacent the sidewall  52  and one pocket  90  for the passage of one leg of one or a plurality of latch means therethrough, as described hereafter. 
     A threaded fastener  100  formed of an enlarged hex-head  102  and an externally threaded shank extending from the head  102  to an end  106  is disposed in each pocket  90 . The shank  104  of each fastener  100  extends through an aperture  108  in the sidewall  52  to allow the threaded shank  104  to extend into the interior of the pocket  90 . 
     As shown more clearly in FIG. 7, the aperture  108  is angularly offset from a nominal perpendicular extent through the sidewall  52  so as to dispose the axis of the aperture  108  as well as the longitudinal axis of the shank  104  of the fastener  100  at a predetermined, non-perpendicular angle with respect to the sidewall  52  of the latch base  10 . The predetermined angle can vary and, by example only, is approximately 5°. This non-perpendicular angle disposes the shank  104  at an non-perpendicular angle with respect to the sidewall  52  to drive a latch means  110  threadingly moved by the fastener  100  into secure engagement with an inner surface  122  of the socket cover  124  shown in a ringless style cover shown in FIG. 6 by levertype action. 
     At least one, and preferably a pair of, bosses or projections  113  are carried on the leg of the latch means  110  through which the shank  104  threadingly extends. The bosses  110  engage the sidewall  52  on full outer positioning of the latch means  110  to lever the opposite end  115  of the latch means  110  into tighter engagement in the direction of arrow  117  with the surface of the socket cover  124 . 
     The fasteners  100  may be formed of any suitable high strength material, such as metal or engineered or reinforced plastics with die-cast zinc being used for example. However, the latch means  110  is preferably formed of metal, such as brass, stainless steel, etc., to minimize corrosion. 
     As shown in FIGS. 4-9, an annular recess typically in the form of circular groove  112  is formed adjacent the end  106  of the shank  104  of each fastener  100 . 
     A fastener latch means  116 , preferably including at least two resilient, spaced latch arms  118 , is integrally formed interiorly of each pocket  90 . The latch arms  118  have spaced inward edges, with an optional annular edge, which are angularly disposed from an end portion of each latch arm  118  extending from an inner surface of the sidewall  92 ,  94  of each pocket  90 . The angled inner ends extend away from the sidewall  52 . 
     During initial insertion of each fastener  100  through the aperture  108  in the sidewall  52 , the end  106  of each fastener  100  will engage and radially deflect the inner ends of the latch arms  118  outward from the longitudinal axis of the shank  104  of the fastener  100  until the enlarged head shaped end  106  passes through the inner ends of the latch arms  118  allowing the ends of the latch arms  118  to snap backward into the recess  112  adjacent the end  106  of the fastener  100  thereby axially locking the fastener  100  with respect to the pocket  110  while enabling the fastener  100  to rotate. 
     In this position, an O-ring  120  mounted in a recess adjacent the head  102  of each fastener  100  sealingly engages the inner surfaces of one aperture  108  in the sidewall  52  of the base  24  to seal each fastener  100  to the latch base to prevent the entry of water or debris along the shank  104  of each fastener  100  into the interior of the latch base  24 . The seal  120  can optionally be mounted in the shoulder formed by the head  102  and shank  104 . 
     As can be seen in FIGS. 6 and 7, rotation of each fastener  100  in one direction will cause the latch means  10  to axially move along the shank  104  of each fastener  100  by means of the thread  111  formed in the aperture of each latch means  110 . This causes the end  113  of the latch means  110 , which may be tapered or beveled, to move radially in and out with respect to the portion  122  of the socket cover  124  surrounding the opening  126  in the socket cover  124  through which the bottom portion of the latch base  24  extends. In the fully extended position of the latch means  110  shown in FIG. 6, the end  113  of the latch means  110  is fully engaged with the inner surface of the portion  122  of the socket cover  124  to securely lock the latch base  24  to the socket cover  124 . Threading rotation of the fastener  100  in an opposite direction will cause the latch means  110  to axially traverse the shank  104  of the fastener  100  to an inboard position shown in FIG. 7 in which the end  113  of the latch means  110  is radially inward of the inner diameter of the aperture  126  in the socket cover  124  to allow the latch base  124  to be withdrawn through the aperture  126 . This inboard position of the latch means  110  also defines an installation position enabling the end  113  of each latch means  110  to clear the inner diameter of the aperture  126  in the socket cover  124  to mount the latch base  24  in the socket cover  124 . 
     According to another aspect of the present invention, at least one ear or flange  130  is carried on the sidewall  52  of the latch base  24 , either through separate attachment to the sidewall  52  or by integral molding with the sidewall  52 . Each ear  130  projections radially outward from the sidewall  52  and includes an aperture  132  opening toward the adjacent fastener head  102 . A through bore  134  is formed in the head  102  of each fastener  100  so as to be alignable with the aperture  132  in the ear  130  when the fastener  100  is rotated to a position to drive the latch means  110  to the fully extended position shown in FIG. 6 locked behind the wall portion  122  of the socket cover  124 . A padlock or wire seal  138 , shown in phantom in FIG. 5, is insertable through the bore  134  and the aperture  132  to indicate a sealed position of the latch base  24  on the socket cover  124 . Since the slots or apertures  134  and  132  ,are cast in the flange  130  and fastener head  102 , manufacturing time is reduced as compared to the prior art ease of separate machining operation to make the apertures. 
     Referring now to FIG. 8, there is depicted the use of the latch base  24  of the present invention with a sealing ring  140 . The sealing ring  140  may be any type of sealing ring used in watthour meter/meter socket adapter applications to secure a watthour meter to a ring style socket cover, to secure a watthour meter to a watthour meter socket adapter, or to secure a watthour meter socket adapter to a ring style meter socket cover. By example, only the sealing ring  140  shown in FIG. 8 is the sealing ring disclosed in U.S. Pat. No. 5,851,038, Assigned to the assignee of the present invention. 
     The sealing ring  140  includes a lock mechanism  142  which lockingly secures separable ends of an annular band about the latch base  24 . As shown in FIG. 8, the annular band of the sealing ring  140  includes a central wall  44  and two opposed outward projecting side walls  146  and  148 . The width of the central wall  144  of the band of the sealing ring  140  is sized to fit about two diametrically opposed flats  101  of the hex-shaped head  102  of each fastener  100 , with the side legs  144  and  146  extending over the flats of the head  102  when one flat  101  is aligned in parallel with the adjacent mounting flange  72 . This uniquely prevents access to a tool or screwdriver receiving slot  148  formed in each head  102  as well as preventing an wrench or other tool from engaging the hex flats on the head  102 . With the lock mechanism  142  fully engaged, the sealing ring  140  prevents detachment of the latch base  24  from the socket cover  124 . 
     As shown in detail in FIGS. 6 and 7, a notch or recess  150  is formed between the outer side edge of each flange  130  and the adjacent mounting flange  72  on the latch base  24 . The recess  150  receives one of the side leg  146  of the sealing ring  140  thereby uniquely enabling the sealing ring  140  to be mounted for the first time over the heads  102  of the drive members  100 . As shown in FIG. 14, when the sealing ring  140  is mounted in the recess or notch  150  between each flange  130  and the adjacent mounting flange  72 , one side leg  146  of the sealing ring  140  will rest on the radially outermost, tapered surface of each rib  75  thereby radially centering the sealing ring over the head  102  of the drive members  100 . 
     Referring now to FIG. 9, there is depicted the use of the latch base  24  and the sealing ring  140  on a ring style meter socket cover  152  having a rolled out flange  154  defining an aperture  156  through which the latch base  24  is mounted. In this type of meter application, the side leg  144  of the sealing ring  140  is disposed in the recess  150  between the head  102  of each fastener  100  and the adjoining mounting flange  72  on the latch base  24 . The opposite side leg  146  of the sealing ring  140  fits over and engages the flange  154  on the socket cover  152  such that the sealing ring  140  spans the mounting flanges  72  and  154  to sealingly mount the latch base  24  to the socket cover  152 . 
     Referring now to FIGS. 10-13, there is depicted a different type of latch means used to mount the latch base  24  on a meter socket cover. 
     In this aspect of the invention, the latch means  160  includes at least one and preferably a plurality, such as two or more, latch members  160  carried in pockets. on the rear surface  162  of the latch base  24 . It will be understood that the optional latch means  160  described hereafter may be used independently of the fasteners  100  and latch members  110  described above and shown in FIGS. 1-9 or in conjunction therewith. 
     Each latch member  160  is typically formed as a one piece member of molded plastic having a generally cylindrical base  162 , and a generally planar arm  164  projecting from the base  162  and supported by an optional rib  166 . The arm  164  terminates in a finger  168  having a first end  170  and an opposed second end  172  which is formed on a depending end portion  174  of the finger  168 . A threaded bore  163  extends through the base  162 . 
     Each latch member  160  is retracted in a pocket in the rear surface  161  of the bottom wall  50  of the latch base  24 , with the bore  163  in each base  162  aligned with the bore  64  extending through one of the mounting bosses  60  projecting from the bottom wall  50  of the latch base  24 . A fastener, such as fastener  180  which can be the same fastener used to secure the shell  26  to the latch base  24 , is inserted through the bore  64  and the base  162  on one latch member  160  and secured in place by a nut  182 . The head  184  of the screw  180  seats against a washer  186  disposed on the end of the mounting boss  64 . The threaded bore  163  in the base  162  of each latch member  160  may be self tapping. 
     The latch members  160  may be formed of any suitable material, such as a glass reinforced plastic, by example only. The nuts  182  are conventional lock nuts having a nylon internal sleeve. 
     The self tapping threads in the bore  163  in the base  162  of each latch member  160  ensure that the latch member  160  remains in a fixed angular position on the fastener  180  so as to be rotatable with rotation of the fastener  180 . An end portion of the nylon insert in the lock nut  182  acts as a bearing surface against one end of the base  162  of the latch member  160 . This engagement allows the nut to be threaded and unthreaded relative to the fastener  180 , while the latch member  160  remains in a fixed position on the fastener  180  after installation of a lock nut  182 . 
     As shown in FIG. 13 for a ring style meter socket cover  152 , the depending end portion  174  of the lock member  160  overhangs the mounting flange  154  on the meter socket cover  152  to lock the latch member  160  to the flange  154 . 
     The opposite ends  72  of the finger  168  of each latch member  160  forcibly engages the rear surface of the mounting flange  72  on the latch base  24  to secure the latch base  24  to the meter socket cover  162 . 
     Once the latch base  24  is mounted on the meter socket cover  152  by tightening the fasteners  180 , access to the fasteners  180  may be had only by removal of the metering device mounted in the latch base  24  to effect removal of the latch base  24  from the meter socket cover  152 . 
     In FIG. 13, one of the latch members  160  is shown engaged with the end portion  122  of a ring style meter socket cover  124  through engagement of the end  170  of the latch member  160  with the rear surface of the edge of the end portion  122  of the ring style socket cover  124 . 
     In both applications shown in FIGS. 12 and 13, the fasteners  180  may be rotated in either direction to rotate the latch member  160  a sufficient angular distance to enable the finger  168  of each latch member  160  to drop below the adjoining surface  122  of the meter socket cover  124  or the flange  154  of the meter socket cover  152  to enable the latch base  24  to be removed from or mounted in the aperture in the respective meter socket covers  124  or  152 . 
     As best shown in FIG. 13, the end  174  of the latch member  160  can serve as a hanger due to the depending end  172  to enable the entire adapter  20  to be temporarily hung during installation from the mounting flange on a ring-style socket cover or from the edge of the opening in a ringless style socket cover. 
     Alternately, a single latch  160  can be provided at a lower end of the adapter  20  and a projection or hook at an opposed or upper end. The projection engages an inner edge of the socket cover, with the latch  160  used to releasably mount the latch base  24  to the socket cover. 
     It will also be understood that certain of the above-identified features of the present invention as usable in a more conventional ringless or ring style mounted watthour meter socket adapter having a housing formed of a separate base and shell which are joined together by fasteners, in addition to the use of such features on the above-described latch base socket adapter. 
     For example, a conventional watthour meter socket adapter with a separately joinable base and shell may utilize the conformable means  80  described on the annular ring of the base as described above and shown in FIG.  5 . 
     The base of such a socket adapter may also include the frangible means  73  in the form of a frangible outer portion of the base flange to enable the base to be convertible from ring style to ringless style meter socket cover mounting. 
     The apertures with  82  with strain relief features  83  described above and shown in FIG. 5 may also be employed in a conventional watthour meter socket adapter base to enable easy passable of conductors from a watthour meter through the socket adapter base. The strain relief fingers not only provide strain relief for such conductors but also provide a locking feature preventing unintended withdrawal of the conductors through the base. 
     Finally, the optional latches  160  shown in FIGS. 10-13 may also be employed on a conventional base to provide means for mounting the base on a ring style or ringless style socket covers. 
     In summary, there has been disclosed a watthour meter socket adapter with a unique latch base which can be easily and securely mounted in either ring style or ringless style meter socket covers to enable recording, surveying and other metering equipment to be mounted to a meter socket cover. Also disclosed in a watthour meter socket adapter with a base and shell for receiving a watthour meter which has numerous improvements for ease of use and reduced manufacturing cost.