Abstract:
An enhanced performance modular plug with a two piece housing is provided. The plug comprises a plurality of contact members each having an insulation displacement contact (IDC) end and a distal end. A first housing portion includes a plurality of slots for receiving the distal end of the plurality of contact members, a first latching assembly for mating the plug with a telecommunications outlet, and a second latching assembly. A second housing portion includes a first end for receiving the second latching assembly and a second end for receiving a cable, the first end having a plurality of channels for receiving a plurality of wires disposed in the cable.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. provisional patent application serial No. 60/119,978 filed Feb. 12, 1999, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to an enhanced performance connector and in particular, to a plug, which is designed for enhanced performance. 
     Improvements in telecommunications systems have resulted in the ability to transmit voice and/or data signals along transmission lines at increasingly higher frequencies. Several industry standards that specify multiple performance levels of twisted-pair cabling components have been established. The primary references, considered by many to be the international benchmarks for commercially based telecommunications components and installations, are standards ANSI/TIA/EIA-568-A (/568) Commercial Building Telecommunications Cabling Standard and 150/IEC 11801 (/11801), generic cabling for customer premises. For example, Category 3, 4 and 5 cable and connecting hardware are specified in both /568 and /11801, as well as other national and regional specifications. In these specifications, transmission requirements for Category 3 components are specified up to 16 MHZ. Transmission requirements for Category 4 components are specified up to 20 MHZ. Transmission requirements for Category 5 components are specified up to 100 MHZ. New standards are being developed continuously and currently it is expected that future standards will require transmission requirements of at least 600 MHZ. 
     The above referenced transmission requirements also specify limits on near-end crosstalk (NEXT). Often, telecommunications connectors utilize pairs of conductive elements commonly known in the art as ring and tip conductors. As telecommunications connectors are reduced in size, adjacent pairs of conductive elements are placed closer to each other creating crosstalk between adjacent pairs. 
     Existing connecting devices include plugs, which are connected to outlets. These plugs can suffer from crosstalk as the rate of transmission increases. To comply with the near-end crosstalk requirements load bars are often utilized to distance the pairs of tip and ring connectors from one another thusly reducing or eliminating NEXT. 
     A typical plug comprises an upper and lower housing, a load bar, terminals having insulation displacement contacts (IDC) to maximize density and ease of use, and a strain relief member. The load bar includes at least one group of channels extending inside of the load bar. The IDC&#39;s are positioned in the upper housing with the cutting edges aligned with a plurality of wire receiving channels within the load bar. The load bar is placed in the lower housing. The cable jacket is stripped exposing the pairs of wires. The end of each pair of wires is untwisted and then inserted through a designated channel within the load bar including the channels extending inside of the load bar. The strain relief member is then connected to and engages the cable sheath to hold the cable tightly. The upper and lower housings are then mounted together punching down the wires into the cutting edges of the IDC. 
     The assembly of the plug is made difficult because of the location of the channels within the load bar and the small diameters of the wire inserted within the channels. The diameter of the wires is typically on the order of 22 to 28 American Wire Gauge (AWG) and, the wires, having very little resistance to deformation, easily buckle upon insertion into the channels. Buckled or bent wire within the channels may easily get stuck and prevent proper passage of the wire through the load bar. Additionally, buckled wire can easily become twisted and, without a method of locating the wires within the plug, the separation of each wire from the others becomes random resulting in some wires being disposed close to, or overlapping the locations of other wires hence increasing NEXT. 
     The cross-sectional ends of the cable used in modular plug applications, as discussed herein above, are typically mirror images of each other requiring two distinct termination assembly procedures. Traditional load bar modular plugs do not accommodate for the mirror image orientation of the cables thus connection assembly is further inhibited. 
     SUMMARY OF THE INVENTION 
     An enhanced performance modular plug with a two piece housing is provided. The plug comprises a plurality of contact members each having an insulation displacement contact (IDC) end and a distal end. A first housing portion includes a plurality of slots for receiving the distal end of the plurality of contact members, a first latching assembly for mating the plug with a telecommunications outlet, and a second latching assembly. A second housing portion includes a first end for receiving the second latching assembly and a second end for receiving a cable, the first end having a plurality of channels for receiving a plurality of wires disposed in the cable. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring now to the drawings wherein like elements are numbered alike in the several FIGURES: 
     FIG. 1 is a perspective view of a plug in accordance with the present invention; 
     FIG. 1A is an exploded perspective view of the plug of FIG. 1; 
     FIG. 2 is a front view of the plug of FIG. 1; 
     FIG. 3 is an exploded side view of the plug of FIG. 1; 
     FIG. 4 is an exploded top view of the plug of FIG. 1; 
     FIG. 5 is a perspective view of the conductor housing; 
     FIG. 6 is an end view of the conductor housing; 
     FIG. 7 is a top view of the conductor housing; 
     FIG. 8 is a front view of the conductor housing; 
     FIG. 9 is a side view of the conductor housing; 
     FIG. 10 is a perspective view of the contact housing; 
     FIG. 11 is an end view of the contact housing; 
     FIG. 12 is a top view of the contact housing; 
     FIG. 13 is a front view of the contact housing; 
     FIG. 14 is a side view of the contact housing; 
     FIGS. 15-18 are views of a first contact; 
     FIGS. 19-22 are views of a second contact; 
     FIG. 23A is a side view of a cable; 
     FIG. 23B is an end view of one end of the cable; and, 
     FIG. 23C is an end view of another end of the cable. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1-4 are views of an enhanced performance plug, shown generally at  100 , in accordance with an exemplary embodiment of the invention. The plug  100  is designed to mate with RJ-45 outlets and includes a contact housing  200  that slides into and engages a conductor housing  300 . Contact and conductor housings are preferably made from resilient plastic but may also be shielded as is known in the art. Contacts  120 ,  150  (FIGS. 15-22) are mounted in the contact housing  200 . A plurality of spaced wire receiving channels  302 ,  304  included in a front face of the conductor housing receive wires and serve to position the wires in the proper location for termination on contacts  120 ,  150 . 
     Referring to FIGS. 5-8, the conductor housing  300  includes a lower planar surface  306 , an opposing upper planar surface  308  and a pair of side walls  310 . The surfaces  306 ,  308  and side walls  310  define opposing front and rear faces  312 ,  314  and a rectangular passage  316  extending from the front face  312  to a substantially circular cutout  318  of the rear face  314 . The side walls  310  have openings  320  for receiving latches  202  that extend from a rear face  204  of the contact housing  200  to be described hereinafter (See FIG.  10 ). Rearwardly extending tapered portions  330  depend from the upper and lower planar surfaces  306 ,  308  at the front face  312  approximate the side walls  310  and extend rearwardly into the rectangular passage  316  to the openings  320  in the side walls for providing a guiding surface for the latches  202 . The upper planar surface  308  includes a step  322  positioned substantially parallel to the front and rear faces  312  and  314 , respectively. 
     Substantially semi-circular channels  302 ,  304  are formed in the upper planar surface  308  of the front face  312  and in the lower planar surface  306  of the front face  312  respectively. The diameter of each channel is a predetermined size smaller than the insulated conductor to be positioned within the channel and resiliently retained therein. The channels  302  in the upper planar surface  308  are positioned in pairs (i.e., tip and ring pairs) with each channel in the pair having a common edge  324  therebetween. Channels  302 - 1  and  302 - 2  define a pair. Channels  302 - 4  and  302 - 5  define a pair. Channels  302 - 7  and  302 - 8  define a pair. Three pairs of channels  302  in the upper planar surface  308  are equally spaced about the center of the front face  312  and offset from the two channels  304  at the lower planar surface  306 , also equally spaced about the center of the front face  312 . Channels  304 - 3  and  304 - 6  define a pair. The longitudinal axis of the channels  302 ,  304  is disposed 90 degrees to the planes of the upper and lower planar surfaces  306 ,  308 . The staggered location of the lower and upper channels along with the special separation between the upper and lower surfaces increases the separation for minimizing NEXT as will be described hereinafter. 
     Referring to FIGS. 10-14, the contact housing  200  includes a lower planar surface  206 , an opposing upper planar surface  208  and a pair of opposing side walls  210 . The surfaces  206 ,  208  and side walls  210  define opposing front and rear faces  212  and  214 , respectively. The dimensions of the surfaces  206 ,  208  and side walls  210  of the contact housing are of a predetermined size for providing an inserting locking engagement with the front face  312  of the conductor housing  300  as will be described in detail hereinafter. A chamfered edge  218  is positioned on the boundary between the upper surface  208  and the front face  212 . 
     Eight slots  220  are defined at the chamfered edge  218  and are dispositioned perpendicular to an axis defined by the chamfered edge. The slots are aligned in accordance with industry standards for contact location to mate to a standard RJ-45 outlet. Each slot  220  is further aligned with an opposing wire receiving channel  302 ,  304  in the conductor housing  300  when the contact housing  200  is inserted into the conductor housing  300 . In particular, slots  220 - 3  and  220 - 6  are aligned with the wire receiving channels in the lower planar surface  306  and receive IDC contacts  150  (see FIG.  19 ). 
     The slots  220 - 1 ,  2 ,  4 ,  5 ,  7 , and  8  are a predetermined size to align and position contacts  120  (see FIG. 15) which are retained therein. The predetermined size and shape of each slot  220 - 1 ,  2 ,  4 ,  5 ,  7 , and  8  is substantially equal to the height H 1  and thickness T 1  of an outlet contact end  122  of IDC contact  120 . 
     With the IDC contacts  120  positioned in their respective slots  220 - 1 ,  2 ,  4 ,  5 ,  7 , and  8  and aligned as described hereinabove, IDC arms  128  extend past the slots  220 - 1 ,  2 ,  4 ,  5 ,  7 ,  8  and are aligned with their respective channels  302  (see FIG.  15 ). 
     The slots  220 - 3  and  6  are also a predetermined size to align and position contacts  150  (see FIG. 19) which are retained therein. The slots  220 - 3 ,  220 - 6  comprise a front portion  236  and a rear portion  238 , as depicted in FIG.  11 . The front portion  236  is a predetermined size and shape substantially equal to the length L, height H 2  and thickness T 2  of the outlet contact end  152  of IDC contact  150 . The rear portion  238  is a predetermined size and shape substantially equal to size and shape of a rear portion of IDC contact  150 . With the IDC contacts  150  positioned in their respective slots and aligned as described hereinabove, the IDC arms  158  extend past the slots  220 - 3 ,  6  and are aligned with their respective channels  304 . 
     The outlet contact end  122 ,  152  of either IDC contact  120 ,  150  (see FIGS. 15,  19 ) is positioned within each slot  220 . A distal surface  132 ,  162  of the outlet contact end  122 ,  152  is positioned approximate to and facing the front face  212  of the contact housing  200 . A chamfered surface  134 ,  164  of the outlet contact end  122 ,  152  is dispositioned approximate to and facing the chamfered edge  218  of the contact housing  200 . Thus, the upper surface  130 ,  160  of the IDC contact is aligned substantially parallel to the upper surface  208  of the contact housing  200 . 
     Referring now to FIG. 12, latches  202 , molded into the contact housing, extend from and beyond the rear face  214  of the contact housing  200  as described hereinbefore. The latches are of a predetermined size for insertion within the rectangular passage  316  of the conductor housing  300  (see FIG.  5 ). A locking portion  222  of each latch  202  includes an outwardly extending step  224  comprising a predetermined size generally equal to the size of the openings  320  in the side walls  310  of the conductor housing  300 . A second surface  226  depends rearward a predetermined distance perpendicularly from the outwardly extending step  224 . A third surface  228  extends rearward and angularly inward at a predetermined angle and a predetermined distance from the second surface  226 . The predetermined dimensions of the second and third surfaces provide for insertion of the locking portion  222  in the openings  320  of the sidewalls  310  of the conductor housing  300  with the second surface  226  positioned substantially within the side walls  310  of the conductor housing  300 . 
     A step  230  is defined at the boundary between the front face  212  and the lower planar surface  206  (see FIG.  14 ). A locking tongue  232  is attached at the step  230  and extends beyond the rear face  214  for locking the plug  100  to an outlet (not shown). 
     As best shown in FIGS. 15-22, first contact  120  and second contact  150  each includes an insulation displacement contact (IDC) end  124 ,  154  and an opposing outlet contact end  122 ,  152 . The IDC end includes IDC arms  128 ,  158 . An upper surface  130 ,  160  of the contact extends to the outlet contact end  122 ,  152 . The outlet contact end  122 ,  152  includes a distal surface,  132 ,  162  and a chamfered surface  134 ,  164  extending from the upper surface  130 ,  160  thereto. All surfaces comprise a predetermined length. The geometry of the outlet contact end  122 ,  152  may comprise many other configurations as is well known in the art. 
     When positioned in the contact housing  200  the arms  128  of the IDC end  124  are substantially aligned with the midpoint of the opposing wire receiving channels  302 - 1 ,  2 ,  4 ,  5 ,  7 ,  8  on the upper planar surface  308  of the conductor housing  300  with the contact housing  200  affixed thereto. A lower surface  136  of the first contact  120  steps down to define a surface  140  substantially parallel to the upper surface  130  of first contact  120  although one skilled in the art would appreciate that the lower surface could include other shapes. 
     The IDC arms  158  are aligned with the midpoint of the opposing wire receiving channels  304 - 3  and  304 - 6  disposed on the lower planar surface  306  of the conductor housing  300  when the contact housing  200  is affixed to the conductor housing  300 . The lower surface  166  of the contact  150  steps up to define a surface  168  substantially parallel to upper surface  160  of contact  150  although one skilled in the art would appreciate that surfaces  166 ,  168  could include other shapes. 
     When assembled, chamfered surfaces  134 ,  164  of the device outlet contact end  122 ,  152  are aligned in a row within slots and IDC ends  124 ,  154  are aligned with there respective channels as described hereinabove. 
     Installation of wires in the conductor housing  300  will now be described. FIGS. 23A and 23B are side and end views, respectively, of a cable having four pairs of wires. The four pairs are labeled Gr (green), Br (brown), Bl (blue) and Or (orange). Each pair includes two wires, one wire designated the tip conductor and the other wire designated the ring conductor. In the un-installed state, the individual wires of each pair are twisted (i.e. the tip and ring conductors are twisted around each other). FIG. 23C is an end view of the opposite end of the cable shown in FIG.  23 B. 
     For the end of the cable shown in FIG. 23B, the channels  302 ,  304  in the conductor housing  300  will be loaded in the following way. First, the cable will be inserted in the rear face  314  and through passage  316  and out the front face  312 . Then, the cable jacket will be stripped off approximately one and one-half inches from the end. Next, pairs Br and Gr will be swapped in position as shown in FIG.  23 B. To do this, pair Gr will cross between pair Br and pair Bl. This will create a separation between pair Br and Bl. Pair Bl is referred to as a split pair because it is spread over an intermediate pair in conventional wiring standards. The tip and ring wires of the Bl pair will be untwisted up to a maximum of one-half inch from the cable jacket, such that the wires in the pair are oriented correctly. The Bl pair will then be pressed into wire receiving channels  304 - 3  and  304 - 6 . The remaining pairs Or, Br and Gr will be untwisted as little as necessary and pressed into their appropriate wire receiving channels  302  such that no pairs are crossed. The tip and ring conductors for each pair are kept adjacent in wire receiving channels  302 ,  304 . The wires are then trimmed as close to the upper and lower surfaces  306 ,  308  as possible. The wires are retained in the channels  302 ,  304  by the compression of the channels against the wires pressed therein resulting from the resilience of the channel material. 
     The pairs that are kept together, Or, Br and Gr are positioned in the upper wire receiving channels  302 . The split pair Bl that straddles another pair Br, in accordance with conventional wiring standards, is pressed in the lower wire receiving channels  304 - 3 ,  304 - 6 . The split pair Bl usually contributes greatly to near end crosstalk (NEXT). By distancing this pair from the other pairs the crosstalk generated by the split pair is reduced. 
     For the end of the cable shown in FIG. 23C the cable housing will be loaded in the following way. First, the cable will be inserted in the rear face  314  and through the passage  316  and out the front face  312 . Then, the cable jacket will be stripped off approximately one and one-half inches from the end. Next pair Or and pair Bl will be swapped in position as shown in FIG.  23 C. To do this, pair Or will cross between pair Br and pair Bl. This will create a separation between pair Br and the split pair Bl. The wires are then pressed in the channels  304 ,  306  on the front face  312  as described above. 
     Assembly of the plug will now be described. The outlet contact ends  122 ,  152  of contacts  120 ,  150  having insulation displacement ends  128 ,  158  facing rearward are positioned in the slots  220  of the contact housing  200 . It is understood that the contacts for the split pair Bl positioned in the wire receiving channels  304 - 3 ,  304 - 6  will be the second contacts  150 . The contact housing  200  is then inserted into the conductor housing  300  with the latches  202  entering the rectangular passage  316  and guided by the rearwardly extending tapered portions  330 . As the contact housing  200  is inserted into the rectangular passage  316  of the conductor housing  300 , the third surfaces  228  of the locking portion  222  of the latches  202  slide along the interior of the side walls  310  and are compressed thereby. The wire receiving channels  302 ,  304  receive the IDC arms  128 ,  158  wherein the IDC arms  128 ,  158  receive the wires and make electrical contact, as is well known in the art. Substantially simultaneously, the outwardly extending steps  224  of the locking portion  222  are received into the openings  320  in the side walls  310  locking therein, thus completing assembly of the plug  100 . 
     Although an eight position plug has been described, it is within the skill of the art to construct variations embodying a ten position, a six position, a four position, and a two position modular plug. 
     While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.