Abstract:
An electrical connector ( 10 ) seatable in a hole ( 16 ) in a enclosure wall ( 14 ) and having an outer conductive shell ( 30 ) containing a dielectric sleeve ( 32 ) holding a seizure contact ( 34 ) at an inner end to compressively engage an inner conductor ( 18 ) of a coaxial cable entering the enclosure ( 12 ). During servicing of the enclosure ( 12 ), the ( 10 ) is matable at an opposed end with a connector ( 100 ) of a jumper cable to connect the jumper cable the to providing uninterrupted CATV service to customers.

Description:
This Application claims benefit to Provisional Application 60/068338 filed Dec. 19, 1997. 
    
    
     FIELD OF THE INVENTION 
     The present invention is related to the field of electrical connectors and more particularly to connectors having seizure screws. 
     BACKGROUND OF THE INVENTION 
     Enclosures are utilized in cable television signal transmission to provide for the eventual interconnection of the coaxial distribution cable to a plurality of subscriber cables, the enclosures being known as signal conditioning/distribution component boxes and being formed of rugged, durable metal suitable for an outside environment that seals the cable exits against moisture entry. It is desired for such enclosures to provide for the use of jumper cables to establish a temporary connection of the incoming main signal distribution cable to the outgoing main signal distribution cable during servicing of the enclosure, thus providing continued service to the existing subscribers. 
     It is desired to adapt the enclosure to facilitate connection of the jumper cable to the incoming and outgoing main distribution cable, and disconnection therefrom. 
     It is also desired that the signal conditioning/distribution component box and its electronic components not be damaged by arcing that may occur during connection or disconnection of a jumper cable. Also, when the jumper cable is not in service, it is desired that signal performance of the signal conditioning/distribution component box not be adversely affected by the presence of the adapter. 
     SUMMARY OF THE INVENTION 
     In the present invention, an adapter is defined that is affixable to the enclosure in a manner that permits connection with and disconnection from a jumper cable at a separable interface, while establishing an electrical connection with the main distribution cable signal conductor by a seizure contact. A separable mechanical interface and seizure contact are integrated into a one piece conductive connector shell. The connector shell includes a threaded portion adjacent the seizure contact at one end thereof, to be threaded into an aperture of the conductive enclosure wall adjacent a subscriber cable exit. The seizure contact is affixed within a large diameter bore end of a dielectric sleeve affixed into the end of the connector shell forwardly of the threaded portion and defines a compression face at an end of the adapter to abut the inner conductor of the main distribution cable at the cable exit of the enclosure. A contact having a plurality of resilient beams defines an annular band of pin-engaging springs for assured current-carrying capability, is disposed within a central cavity of the seizure contact open away from the compression face and toward the separable mating interface aligned with a small diameter bore of the dielectric sleeve; the annular contact band is matable with an elongate pin of a mating connector upon mating at the separable interface at an end opposed to the seizure contact. The adapter and the matable connector may utilize a bayonet-style coupling (BNC) to facilitate mating and unmating. 
     An embodiment of the invention will now be described by way of example with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a longitudinal cross-sectional view of the adapter assembly of the present invention disposed in a enclosure wall abutting a coaxial cable inner conductor; 
     FIG. 2 is an exploded longitudinal cross-sectional view of the adapter assembly of FIG. 1; 
     FIGS. 3 and 4 are longitudinal cross-sectional assembly and exploded views of a connector matable with the adapter assembly of FIGS. 1 and 2; and 
     FIG. 5 is a longitudinal cross-sectional view of the connectors of FIGS. 1 to  4  in mated condition. 
    
    
     DETAILED DESCRIPTION 
     Adapter  10  is shown in FIG. 1 affixed in a wall  14  of a conductive enclosure  12 , threaded into a hole  16  thereof and abutting an inner conductor  18  of a coaxial cable  20  entering a cable exit  22  of the enclosure, the adapter being orthogonal to inner conductor  18 . It is seen that inner conductor  18  of main signal distribution cable  20  is in electrical connection with a terminal  76  extending to the interior of enclosure  12  for electrical connection to the signal conditioning/distribution circuitry during normal service. A preferably low resilience dielectric platform  78  isolates the terminal  76  from the enclosure wall while providing for assured electrical engagement of the inner conductor against the terminal when pressed thereagainst by the seizure screw of adapter  10 . A dielectric sleeve  80  surrounds inner conductor  18  to electrically isolate it from the enclosure wall, with dielectric sleeve  80  preferably being of elastomeric material to provide sealing at the cable exit. 
     Adapter  10  of FIGS. 1 and 2 includes a conductive shell  30 , a dielectric sleeve  32 , a seizure contact  34  and a annular contact band  36 . Dielectric sleeve  32  is disposed at a first end  38  of shell  30  in a large diameter bore  40  thereof forwardly of a threaded outer surface region  42  of shell  30 . Seizure contact  34  is affixed in a large diameter passageway portion  44  of dielectric sleeve  32  at leading end  46  thereof, by interference fit such as by retention barbs  48  along flange  50  thereof that bite into inner surfaces of passageway portion  44 . Annular contact band  36  is disposed in a central cavity  52  of seizure contact  34  such as by friction fit, the blind bore opening onto smaller diameter passageway portion  54  of dielectric sleeve  32 . Seizure contact  34  defines an imperforate abutment surface  56  along leading end  58  thereof to abut the coaxial cable inner conductor  18  under compression upon adapter being threaded into hole  16  of enclosure  12 . 
     Separable mating interface  60  of adapter  10  is defined by a shroud  62  of conductive outer shell  30  defining a large cavity  64  extending to second end  66  of dielectric sleeve  32  and in communication with and aligned with smaller diameter passageway portion  54  thereof. Shroud  62  includes a plurality of outwardly extending bosses  68  to provide for a bayonet style coupling with the mating connector  100  (FIGS. 3 to  5 ) at the separable mating interface  60 , as seen in FIG. 5, and using a coupling ring  108  of connector  100 . Alternatively, the coupling ring may be placed on the adapter and a shroud with pins placed on the mating connector. 
     Smaller diameter passageway portion  54  includes a chamfered pin-receiving entrance  70  to facilitate receipt thereinto of the leading end of the elongate pin contact of mating connector  100 . Annular groove  72  along outer surface  74  of dielectric sleeve  32  enhances dielectric properties of the connector for coaxial transmission. 
     Mating connector  100  is of the coaxial type generally termed a BNC plug, and is seen in FIGS. 3 and 4 to include an outer conductor assembly  102 , dielectric sleeve  104 , inner contact  106  and a coupling ring  108 . Inner contact  106  includes an elongate pin contact section  110  protruding beyond the leading end  112  of the outer conductor assembly  102  and the coupling ring  108 , and also includes a socket contact section  114  seated within bore  116  of dielectric sleeve  104  into which is received an inner conductor of a coaxial jumper cable (not shown), which is crimped or preferably soldered thereto. 
     Outer conductor assembly  102  is seen to include a forward member  118  and a rearward member  120 , with dielectric sleeve  104  seated in a forward end  122  of rearward member  120  such as by embossments  124  disposed in an annular groove  126  surrounding the dielectric sleeve. Forward member  118  is movable with respect to rearward member  120  along the outer surfaces of forward end  122 , and is trapped in coupling ring  108  by outturned flange  128  adjacent to a gasket  130  and both disposed behind a ledge  132  of the coupling ring. Forward member  118  includes a forward end defining a plurality of beams  134  adapted to be compressed upon insertion into shroud  62  of conductive shell  30  of adapter  10  (see FIG.  5 ). 
     Mating connector  100  is seen to include a transverse rear plate  136  trapped in trailing end  138  of coupling ring  108  rearwardly of forward outer conductor member  118  by inturned end  140  of the coupling ring. Rear plate  136  forwardly biases a Belleville washer  142  to abut a rearwardly facing surface  144  of forward outer conductor member  118  along an outturned flange  128  thereof. Rearward end  146  of rearward outer conductor member  120  defines a flange preferably with a knurled outer surface  148  for establishing a grounding connection with the shield braid of the jumper cable (not shown). 
     Coupling ring  108  is seen in FIG. 4 to define a pin-receiving slot  150  corresponding to each pin  68  of the shroud of adapter  10  and extending from an entrance adjacent leading end  152  of the coupling ring at a larger diameter leading end portion  154  thereof, the pin-receiving slot extending helically around a smaller diameter portion  156  of the coupling ring for a selected angular distance such as a quarter of the circumference. Pin-receiving slot  150  concludes in a pin seat  158  so that a pin may become seated in the pin seat (FIG. 5) upon full mating of the connectors after having first entered the slot entrance near the leading end  152  of the coupling ring. 
     During in-service use of the adapter as a temporary connection, mating connector  100  is terminated onto an end of a jumper coaxial cable and is matable with and unmatable from adapter  10  at separable interface  60 , with adapter  10  being fixed in threaded hole  16  of enclosure  12  and remaining continuously in electrical contact with inner conductor  18  of the subscriber cable  20 . During in-service use when the jumper cable is not connected thereto, the adapter will not abnormally act as an antenna even though its contact remains engaged with inner conductor  18 ; use of the annular contact band within a drilled bore of the seizure contact does not result in an undesirable antenna effect, unlike socket contacts that extend outwardly into the separable mating interface. 
     Adapter  10  is adapted to be retrofitted into existing in-service enclosures, having the same outer envelope at the forward end as existing adapters. The annular contact band  36  may be of the conventional type sold by AMP Incorporated and known as the AMP Louvertac Band contact with a proven current-carrying capability of  15  amperes and “hot” mate and unmate capability, with an array of concave springs therealong to grip the outer surface of the elongate pin contact section of mating connector  100 . Although some level of arcing may occur during “hot” mating and unmating, such arcing would be safely contained entirely within the adapter remote from any electronic components of the signal conditioning/distribution component box. The contact band is friction fitted into a drilled bore of the seizure contact, providing compensation for diametrical tolerance stack-up. The elongated array of concave springs are sized to provide compensation for longitudinal tolerance stack-up between the adapter and the mating connector.