Patent Document

This application claims the priority of Provisional U.S. Patent Application Ser. No. 62/006,061 filed May 31, 2014. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to electrical fittings or connectors for connecting electrical cables to a panel and specifically to a duplex electrical fitting or connector having a two-piece connector body in which the body pieces can be easily disconnected and slid apart for inspection or reconnection of an electrical cable to the trailing end of the fitting. 
     BACKGROUND 
     Duplex quick-connect electrical fittings are commonly used to rapidly connect two electrical cables to a single knockout aperture in an electrical box or electrical panel. Duplex quick-connect electrical fittings typically include a two-piece connector body having a trailing body portion with two bores therein for insertion of electrical cables and a leading body portion with a single bore therein for insertion into a knockout aperture of the electrical panel. 
     In a typical two-piece duplex quick-connect electrical fitting, the leading body portion includes an opening that accepts the trailing body portion and the two pieces are pressed together and connected by a screw or similar fastener. The two body portions are typically axially aligned and connected end-to-end, with the trailing body portion pressed within the opening of the leading body portion. Constructing a duplex fitting with axially aligned and joined end-to-end body portions typically adds substantial width and length to the resultant fitting as the leading body portion must be made large enough to accept the entire trailing body portion. 
     The amount of metallic alloy material used to construct the connector body portions directly affects the cost of the resultant fitting. It is therefore advantageous for manufacturers to minimize the size of the body portions to reduce unit production costs. Furthermore, there are times when an installer must disassemble the duplex fitting after it has been initially connected to a box or panel, such as for inspection or removal of the inserted electrical cables. In a conventional two-piece duplex fitting, it is difficult to separate the two body portions in order to inspect or remove the connected electrical cables. 
     Accordingly, what is needed is a duplex electrical fitting that lowers unit production costs. Furthermore, the duplex electrical fitting must be capable of being easily disassembled after connection to an electrical box to allow inspection of the inserted electrical cables. 
     BRIEF SUMMARY OF THE INVENTION 
     The current invention is a duplex electrical connector including a front connector body slidably connected to a rear connector body. The front connector body includes a leading end, a trailing end with a bottom periphery, a top side, a nose portion at the leading end, and a leading bore therein. The rear connector body includes a leading end, a trailing end, and two internal bores extending from the trailing end to the leading end. A lip extends along the top side of the trailing end of the front connector body. A tab with an aperture therein extends from the top lip. A front extension extends from the leading end of the rear connector body. A trailing flange extends along the bottom periphery of the trailing end of the front connector body. Rear connector body includes a boss having an aperture therein, with the axis of the bore at substantially a right angle with respect to the axes through the internal bores through the rear connector body. Front connector body is assembled to rear connector body by sliding the trailing flange of front connector body into open channel of front extension of rear connector body and affixing a screw through tab of front connector body into the boss of rear connector body. Such sliding assembly of the connector bodies enables minimizing the size of the connector bodies while enabling easy disassembly of the two connector body portions for inspection of internal cable connections. Nose portion of front connector body includes a seat and a snap ring disposed on the seat to facilitate connection of the duplex electrical connector to an electrical box or panel. A cable retaining ring secured in each internal bore in the rear connector body enables rapid and easy snap in connection of metal clad or armor clad cable to the trailing end of the duplex electrical connector. 
     OBJECTS AND ADVANTAGES 
     A first object of the current invention is to provide a duplex electrical fitting that enables easy snap-in insertion of an electrical cable into an electrical box, including easy snap-in insertion of an electrical cable at the trailing end of the fitting and easy snap-in insertion of the leading end of the fitting into the knockout of the electrical box. 
     A second object of the invention is to enable a reduction in size to realize a reduction in the unit production costs of duplex electrical fittings. 
     A further object of the invention is to provide a duplex electrical fitting including a two-piece connector body that may be easily disassembled for inspection of electrical cable connections. 
     A further object of the invention is to provide a two-piece duplex electrical fitting in which the pieces assemble and disassemble in a sliding manner, the direction of the assembly and disassembly being at substantially right angles to the axes of bores extending through the two-piece fitting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of the preferred embodiment of a duplex electrical connector according to the present invention. 
         FIG. 2  is a top view of a front connector body that forms a portion of the duplex electrical connector shown in  FIG. 1 . 
         FIG. 3  is a side view of the front connector body. 
         FIG. 4  is a bottom view of the front connector body. 
         FIG. 5  is a sectional view of the front connector body taken along line  5 - 5  of  FIG. 3 . 
         FIG. 6  is a sectional view of the front connector body taken along line  6 - 6  of  FIG. 4 . 
         FIG. 7  is a bottom perspective view of the front connector body 
         FIG. 8  is a top view of a rear connector body that forms a portion of the duplex electrical connector shown in  FIG. 1 . 
         FIG. 9  is a side view of the rear connector body as viewed from the right side of  FIG. 8 . 
         FIG. 10  is an end view of the rear connector body as viewed from the bottom of  FIG. 8 . 
         FIG. 11  is a sectional view of the rear connector body taken along line  11 - 11  of  FIG. 10 . 
         FIG. 12  is a sectional view of the rear connector body taken along line  12 - 12  of  FIG. 10 . 
         FIG. 13  is a sectional view of the rear connector body taken along line  13 - 13  of  FIG. 10 . 
         FIG. 14  is a top perspective view of the rear connector body. 
         FIG. 15  is a bottom perspective view of the rear connector body. 
         FIG. 16  is a top view of a duplex electrical connector assembly according to the present invention. 
         FIG. 17  is a side view of the duplex electrical connector assembly. 
         FIG. 18  is an end view of the duplex electrical connector assembly from the trailing end. 
         FIG. 19  is a sectional view of the duplex electrical connector assembly taken along line  19 - 19  of  FIG. 18 . 
         FIG. 20  is a sectional view of the duplex electrical connector assembly taken along line  20 - 20  of  FIG. 18 . 
         FIG. 21  is a detail view of the portion of the duplex electrical connector assembly circled in  FIG. 20 . 
         FIG. 22  is a sectional view of the duplex electrical connector assembly taken along line  22 - 22  of  FIG. 16 . 
         FIG. 23  is a top isometric view of the duplex electrical connector assembly as viewed from the leading end. 
         FIG. 24  is a top isometric view of the duplex electrical connector assembly as viewed from the trailing end. 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIG. 1  there is shown a preferred embodiment of the present invention, a duplex electrical connector  20  that is an assembly of a two-piece die cast connector body  22  including a front connector body  24  and a rear connector body  26 . The front connector body  24  and rear connector body  26  are slideably connectable to one another along lines  27  as shown in  FIG. 1 . The front connector body  24  includes a nose portion  28  and a leading end  30  and a trailing end  32 . A fastening arrangement  34  is included on the leading end of the front connector body  22  for fastening the duplex electrical connector  20  to an electrical panel or junction box (not shown). The fastening arrangement  34  includes a seat  36  on the nose portion  28  and a snap ring  38  that is shown exploded away from the leading end  30  of the front connector body  24 . The rear connector body  26  includes a leading end  40 , a trailing end  42  with two bores  44  therein, and a cable retaining ring  46  inserted in each trailing bore  44 . A throat insert  48  is inserted the nose portion  28  of the front connector body  26  and a fastener  50  secures the front connector body  24  and rear connector body  26  together. 
     Referring to  FIGS. 2-4 , the front connector body  24  includes a top side  52 , a bottom side  54 , and a lip  56  extending from the top side  52  of the front connector body  24  at the trailing end  32 . A tab  58  extends from the lip  56  at the top side  52  of the front connector body  24  as shown in  FIG. 3  and includes an aperture  60  therein. The front connector body  24  further includes a leading flange  62  and an intermediate flange  64  surrounding the seat  36 . A trailing flange  65  extends along the bottom periphery of the trailing end  32 . The front connector body further includes rounded shoulders  66 . Two viewports  68  are included on both the top side  52  and bottom side  54  of the front connector body  24 . 
     With reference to  FIGS. 5-7 , the front connector body  24  includes a wide bore  70  at the trailing end  32  narrowing to a narrower leading bore  72 . The interior walls  74  that form the transition from the wide bore  70  to the leading bore  72  are smooth, gradually arcuate, and devoid of sharp edges to enable easy passage of wire conductors from the wide bore  70  to the leading bore  72 . Each viewport  68  on the top side  52  is axially aligned with a viewport on the bottom side  54  of the front connector body  24  as shown by axis  76  in  FIG. 7 . 
     Referring to  FIGS. 8-10 , the rear connector body  26  includes a top side  78 , a bottom side  80 , and a front extension  82  extending from the leading end  40 . The front extension  82  extends from the lower half of the rear connector body and includes an open channel  84  therein. A boss  86  is included on the top side  78  of the rear connector body  26  and includes an aperture  88  therein. Two semi-circular notches  90  are included in the front extension  82 . Openings  92 A and  92 B are included in the rear connector body  26 , with each opening in communication with one of the trailing bores  44 . As shown in  FIG. 10 , the front extension  82  may include outer portions  82 A and an inner portion  82 B separated by the semi-circular notches  90 . As shown in  FIGS. 14 and 15 , a rim  91  extends from the outer periphery  93  of the rear connector body  26  at the leading end  40 . 
     With reference to  FIGS. 16 and 17 , the duplex electrical connector  20  is assembled by securing front connector body  24  and rear connector body  26  together with fastener  50  to form a two-piece die cast connector body  22 . Snap ring  38 , which is preferably a split ring formed of a resilient metal and in its unbiased state includes a diameter smaller than the diameter of the seat  36 , is slightly expanded to slip over the leading flange  62  and is then secured onto the seat  36  on the nose portion  28  of front connector body  24 . The snap ring  38  includes locking tangs  94  thereon. The locking tangs  94  will function to secure the leading end  30  of the duplex electrical connector  20  to an electrical box or panel. Leading flange  62  and intermediate flange  64  surround the seat  36  and hold snap ring  38  in place on the connector. 
     A cable retaining ring  46 , which is preferably a split ring formed of a resilient metal and in its unbiased state includes a diameter larger than the diameter of each of the trailing bores  44 , is slightly compressed and then slipped into each of the trailing bores  44 . Locking tangs  96  on the cable retaining rings  46  snap into openings  92 A and  92 B in rear connector body  26  and hold the cable retaining rings securely within the trailing bores  44 . Throat insert  48 , preferably constructed of plastic, is pressed into the leading bore  72  (see  FIG. 6 ) of front connector body  24  and held therein by a friction fit. Throat insert  48 , optional for use on the duplex electrical connector  20 , acts to shield wire conductors from the interior of the leading bore in order to minimize fraying or abrasion of the outer sheath of the conductors (not shown). 
     With reference to  FIGS. 18 and 19 , each cable retaining ring  46  includes three cable retaining tangs  98  extending inward of the cable retaining ring, including a center tang  98 A and two outer tangs  98 B. Center tang  98 A includes a flat end  101  that is perpendicular to the sides  103  of the center tang. Outer tangs  98 B include ends  105  that are angled with respect to the sides  107  of the outer tangs. The orientation of the tangs  98 A and  98 B with respect to the duplex connector are set by the arrangement of the openings  92 A and  92 B (see  FIG. 14 ) in the rear connector body  26 . Outer tangs  92 B are positioned such that the short sides  107  are oriented toward the center  109  of the duplex connector and toward opposing quadrants. As shown in  FIG. 18 , when an electrical cable is inserted within the left trailing bore  44 A, the tangs  98 A and  98 B in the left trailing bore push the cable toward the center of the connector and toward the right lower quadrant of the bore  44 A, or in the direction of arrow  111  in  FIG. 18 . When an electrical cable is inserted within the right trailing bore  44 B, the tangs  98 A and  98 B in the right trailing bore push the cable toward the center of the connector and toward left upper quadrant of the bore  44 B, or in the direction of arrow  113  in  FIG. 18 . The orientation of the tangs  98 A and  98 B therefore advantageously maintain separation of the electrical cables and direct them toward the center of the leading bore (see  FIG. 6 ). 
     Referring to  FIGS. 20-22 , to secure the two connector body portions  24  and  26  together, front connector body  24  is slid sideways with respect to rear connector body  26  in the direction of arrow  115  until trailing flange  65  of front connector body latches into open channel  84  on front extension  82  of rear connector body  26 . Fastener  50  is then secured through aperture  60  in tab  58  of front connector body  24  into aperture  88  in rear connector body  26 . 
     With reference to  FIGS. 23 and 24 , the duplex electrical connector  20  includes a leading end  117  and a trailing end  119 . The connector is used to secure one or two electrical cables (not shown) to a panel or an electrical box. To operate the invention, leading end  117  is simply pressed into the knockout of an electrical box. Locking tangs  94  on snap ring  38 , being constructed of resilient metal such as spring steel, deflect inward when in contact with the walls of the knockout and then spring outward to their unbiased position after clearing the wall. The leading end is then securely locked into the knockout in the electrical box. One or two electrical cables (not shown) are then inserted into the bores  44  on the trailing end  119  of the duplex connector  20 . The three cable retaining tangs  98 A and  98 B (see  FIG. 18 ), then direct each electrical cable to the center of the connector and the proper quadrant, after which the electrical cables are locked securely to the duplex connector  20 . The types of electrical cables and conduits that can be connector to an electrical box with the duplex electrical connector  20  include MC/HCF steel or aluminum cable, AC/HCF steel or aluminum cable, flexible metal conduit steel and aluminum, including both regular and reduced wall thickness, and MC cable continuous corrugated aluminum. 
     With reference to  FIG. 1 , the present invention provides a method for securing an electrical cable to an electrical box, the method including:
         a. providing a duplex fitting  20  including a front connector body  24  having a leading end  30 , a trailing end  32  including a lip  56  and a trailing flange  65 , and a tab  58  with an aperture  68  therein;   b. providing a rear connector body  26  having a leading end  40  including a front extension  82 , an open channel  84 , and a rim  91 , and a boss  86  with a bore  88  therein;   c. pressing the trailing end  32  of the front connector body  24  against the leading end  40  of the rear connector body  26 ;   d. sliding the trailing end  32  of the front connector body  24  along the leading end  40  of the rear connector body  26  until the trailing flange  65  of the front connector body  24  engages the open channel  84  in the rear connector body  26  and the lip  56  of the front connector body  24  engages the rim of the rear connector body  26 ; and   e. threading a screw  50  through the aperture  68  in the tab  58  of said front connector body  24  and into the bore  88  of the boss  86  of the rear connector body  26 .       

     Preferably, the front connector body  24  and rear connector body  26  are each die-cast in one-piece of zinc alloy. The snap ring  38  and cable retaining rings  46  are preferably constructed of spring steel. The throat insert  48  is preferably constructed of plastic. 
     Although the description above contains many specific descriptions, materials, and dimensions, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.

Technology Category: h