Abstract:
A wire containment cap includes a first side having a plurality of retainers for retaining wires, and a second side opposite the first side. Two sidewalls extend between the first side and the second side, and a support rib extends between the two sidewalls. The support rib includes two pair separators for separating wire pairs. In one embodiment, a plurality of sloped pair splitters is located between two of the retainers and includes a sharp point for cutting through insulation material on a pair of bonded wires. A communication jack assembly including a front portion and the wire containment cap is also described.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 11/195,412, filed Aug. 2, 2005, which claims the benefit of U.S. Provisional Application No. 60/598,640, filed Aug. 4, 2004 and U.S. Provisional Application No. 60/637,247, filed Dec. 17, 2004, which are incorporated herein by reference in their entireties. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to electrical connectors, and more particularly, to a modular communication jack design with an improved wire containment cap. 
       BACKGROUND OF THE INVENTION 
       [0003]    In the communications industry, as data transmission rates have steadily increased, crosstalk due to capacitive and inductive couplings among the closely spaced parallel conductors within the jack and/or plug has become increasingly problematic. Modular connectors with improved crosstalk performance have been designed to meet the increasingly demanding standards. Many of these connectors have addressed crosstalk by compensating at the front end of the jack, i.e., the end closest to where a plug is inserted into the jack. However, the wire pairs terminated to the insulation displacement contact (“IDC”) terminals at the rear portion of a jack may also affect the performance of the jack. 
         [0004]    One problem that exists when terminating wire pairs to the IDC terminals of a jack is the effect that termination has on the crosstalk performance of a jack. When a twisted pair cable with four wire pairs is aligned and terminated to the IDC terminals of a jack, a wire pair may need to flip over or under another wire pair. An individual conductor of a wire pair may also be untwisted and oriented closely to a conductor from a different wire pair. Both of these conditions may result in unintended coupling in the termination area which can degrade the crosstalk performance of the jack. Thus, a solution addressing the crosstalk in the termination area of the jack would be desirable. This solution should produce a termination that is as noiseless as possible to minimize the crosstalk of that termination. 
         [0005]    A second problem that exists when terminating wire pairs to the IDC terminals of a jack is variability. A technician is typically called on to properly terminate the wire pairs of a twisted pair cable to the proper IDC terminals of the jack. Each jack terminated by the technician should have similar crosstalk performance. This requires the termination to remain consistent from jack to jack. However, different installers may use slightly different techniques to separate out the wire pairs and route them to their proper IDC terminals. Thus, a solution that controls the variability of terminations from jack to jack would be desirable. 
         [0006]    A final issue that arises when terminating wire pairs to the IDC terminals of a jack is the difficulty of the termination process. Typical jacks provide little assistance to the technician, resulting in occasional misterminations (e.g. a wire being terminated at an incorrect location in the jack). Even if detailed instructions are provided with the jack, technicians may not read these instructions prior to installing the jacks. Furthermore, a jack with a difficult termination process can increase the installation time for the technician and result in a costly installation for the customer. Thus, a jack solution that simplifies the termination process and minimizes the possibility of technician error would be desirable. 
       SUMMARY 
       [0007]    The present application meets the shortcomings of the prior art by providing a wire containment cap having a first side including a plurality of retainers for retaining wires, a second side being opposite the first side, two sidewalls extending between the first side and the second side, a support rib extending between the two sidewalls and including two pair separators for separating a pair of wires, and a plurality of sloped pair separators located between two of the retainers and including a sharp point for cutting through insulation material on a pair of bonded wires. 
         [0008]    A communication jack assembly is also described. The communication jack comprises a front portion including a retention clip, and a wire containment cap including a retention recess for securing the wire containment cap to the front portion. The wire containment cap comprises a first side including a plurality of retainers for retaining wires, a second side being opposite the first side, two sidewalls extending between the first side and the second side, a support rib extending between the two sidewalls and including two pair separators for separating a pair of wires, and a plurality of sloped pair separators located between two of the retainers and including a sharp point for cutting through insulation material on a pair of bonded wires. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0009]      FIG. 1  is a front upper right perspective view of a communication jack having a wire containment cap in accordance with an embodiment of the present invention; 
           [0010]      FIG. 2  is a front upper right partial-exploded view of the communication jack of  FIG. 1 ; 
           [0011]      FIG. 3  is a front upper right perspective view of a wire containment cap in accordance with an embodiment of the present invention; 
           [0012]      FIG. 4  is a rear upper left perspective view of a wire containment cap in accordance with an embodiment of the present invention; 
           [0013]      FIG. 5  is a rear isometric view of a wire containment cap in accordance with an embodiment of the present invention, showing cross-sections  6 - 6  and  7 - 7 ; 
           [0014]      FIG. 6  is a cross-sectional view of a wire containment cap taken across cross section  6 - 6  from  FIG. 5 , in accordance with an embodiment of the present invention; 
           [0015]      FIG. 7  is a cross-sectional view of a wire containment cap taken across cross section  7 - 7  from  FIG. 5 , in accordance with an embodiment of the present invention; 
           [0016]      FIG. 8  is a conceptual diagram illustrating a wire pair alignment of opposite ends of a typical twisted pair cable with one example of an IDC terminal layout; 
           [0017]      FIG. 9  illustrates diagrams  300  of six alternate IDC terminal layout arrangements along with the corresponding wire containment cap design for each of the arrangements. The diagrams  302 ,  304 ,  306 ,  308 ,  310 , and  312  merely provide examples of different terminal layouts for IDCs  1 - 8  and different wire containment cap designs, but these diagrams do not comprise all of the possible design options available; 
           [0018]      FIG. 10  is an upper right perspective view of a wire containment cap in accordance with an embodiment of the present invention; and 
           [0019]      FIG. 11  is a lower left perspective view of a wire containment cap in accordance with an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]      FIG. 1  is a front upper right perspective view of a communication jack  100  in accordance with an embodiment of the present invention. The communication jack  100  includes a front portion  102  and a wire containment cap  104 . The front portion  102  may include such components as plug interface contacts, a mechanism for coupling the jack to a plug, crosstalk compensation circuitry, and wire-displacement contacts to provide an electrical connection between the jack and a communication cable. Additional details on the wire containment cap  104  are described with reference to  FIGS. 3-7 , below. 
         [0021]      FIG. 2  is a front upper right partial-exploded view of the communication jack  100  of  FIG. 1 . In the embodiment shown, the wire containment cap  104  is slidably mounted within the front portion  102 . A retention clip  105  on the front portion  102  and a retention recess  108  on the wire containment cap  104  may be included to secure the wire containment cap  104  to the front portion  102 . Other mounting and securing techniques may also be used. 
         [0022]      FIGS. 3-7  illustrate the wire containment cap  104  in further detail, in accordance with an embodiment of the present invention. The wire containment cap  104  includes a large opening in the back to allow a cable to be inserted, and allow the pairs to separate quickly as they transition toward IDC terminals. The opening consists of four individual quadrants with a spine  110  between pairs to minimize cable interaction. In addition to the retention recess  108  described above with reference to  FIG. 2 , the wire containment cap  104  includes a shoulder  106 , a spine  110 , two pair separators  112 , a support rib  114  to support each pair separator  112 , upper wire retainers  116 , and lower wire retainers  118 .  FIGS. 3-7  illustrate additional details as well, such as a possible frame shape for the wire containment cap  104 . In a preferred embodiment, the wire containment cap  104  is constructed of a plastic material, such as polycarbonate. Alternative materials, shapes, and subcomponents could be utilized instead of what is illustrated in  FIGS. 3-7 . 
         [0023]    The shoulder  106  serves as a support and stopping mechanism to place the wire containment cap  104  in a correct physical position with respect to the front portion  102  shown in  FIGS. 1 and 2 . Alternative support and/or stopping mechanisms could also be used, such as one located on the front portion  102 , or on the wire containment cap  104  in such a position that it abuts an interior location in the front portion  102 , rather than the exterior abutment shown in  FIGS. 1 and 2 . 
         [0024]    The pair separators  112  are supported by the spine  110  and support rib  114 , and are positioned generally perpendicular to the support rib  114 . The pair separators  112  are advantageous because when the wire pairs are aligned with the IDC terminals, at least one wire pair will typically have to flip over or under the other pairs on at least one end of a twisted pair cable. One reason this flip may occur is because the wire pair layout on one end of a twisted pair cable is a mirror image of the wire pair layout on the opposite end of the twisted pair cable. Another reason this flip may occur is because the Telecommunications Industry Association (“TIA”) standards allow structured cabling systems to be wired using two different wiring schemes. Finally, a flip may occur because not all cables have the same pair layout. 
         [0025]    The relatively open design of the wire containment cap  104  shown in  FIGS. 3-6  is due in large part to the spine  110  and support rib  114  being relatively thin. This open space allows a technician to more freely move wire pairs and individual wires within the wire containment cap  104  to make any required flips or bends. To complete the installation, the technician need only place wire pairs on the appropriate sides of the pair separators  112 , secure individual wire pairs in the upper and lower wire retainers  116 ,  118 , and attach the wire containment cap  104  to the front portion  102 . 
         [0026]      FIG. 8  is a conceptual diagram  200  illustrating the wire pair alignment of opposite ends of a typical twisted pair cable. The example shown is an IDC terminal layout designed to match a typical twisted pair cable when that cable is wired with the more commonly used 568-B wiring scheme. In diagram  202  and diagram  204 , the wire pairs are aligned according to the 568-A wiring scheme. Under 568-A, the green wire pair of the twisted pair cable should be terminated to IDC terminal (1,2), the orange wire pair should be terminated to IDC terminal (3,6), the blue wire pair should be terminated to IDC terminal (4,5), and the brown wire pair should be terminated to IDC terminal (7,8). Diagram  202  illustrates the 568-A alignment of the wire pairs on one end of the twisted pair cable where the blue wire pair and the brown wire pair must be flipped in order to terminate those wire pairs to the appropriate IDC terminals. Diagram  204  illustrates the 568-A alignment of the wire pairs on the other end of the twisted pair cable shown in diagram  202 . The wire layout in diagram  204  is a mirror image of the wire pair layout in diagram  202  and therefore different pairs are flipped. Diagram  204  shows the green wire pair and orange wire pair being flipped in order to terminate those wire pairs to the appropriate IDC terminal. 
         [0027]    Diagram  206  and diagram  208  illustrate wire pairs aligned according to the more commonly used 568-B wiring scheme. Under 568-B, the alignment of the blue wire pair and the brown wire pair should not change from 568-A but the orange wire pair should now be terminated to IDC terminal (1,2) and the green pair should now be terminated to IDC terminal (3,6). Diagram  206  illustrates the 568-B alignment of the wire pairs on one end of the twisted pair cable where the wire pairs are matched to the IDC terminals and no wire pair flipping is necessary. Diagram  208  illustrates the 568-B alignment of the wire pairs on the other end of the twisted pair cable shown in diagram  206 . The wire layout in diagram  208  is a mirror image of the wire pair layout in diagram  206  and therefore wire pairs are flipped. Diagram  208  shows the green wire pair being flipped with the orange wire pair and the blue wire pair being flipped with the brown wire pair in order to terminate those wire pairs to the appropriate IDC terminals. 
         [0028]    Referring back to  FIGS. 3-7 , the pair separators  112  are employed to minimize the interaction of wire pairs when they need to be flipped as described above. The separators  112  help to ensure that the wire pairs will only cross each other top to bottom or side to side, but not a combination of both. 
         [0029]    The upper and lower wire retainers  116 ,  118  are positioned to present the terminated wires to the front portion  102 , preferably in a perpendicular orientation to IDC terminals that may be included as part of the front portion  102 . In the illustrated embodiment, each wire retainers  116 ,  118  includes an inner portion and an outer portion (wire restraining features), with an intermediate portion through which the IDC terminals may make electrical contact with the wire by piercing insulation on the wire to make a metallic contact. The inner and outer portions in essence serve as bridge supports on either end of the wire to allow the wire insulation to be pierced when the wire containment cap is pressed into the front portion  102 . The wire retainers  116 ,  118  are preferably spaced at regular intervals to allow for consistent pair-to-pair separation. When utilized in combination with the spine  110 , pair separators  112 , and support rib  114 , improved electrical performance may be realized. 
         [0030]    In typical operation, an installer may place a cable having an outer jacket diameter up to 0.310″ into the rear of the wire containment cap  104  and separately route each twisted wire pair (blue, green, orange, and brown) as appropriate. As a result, the wire termination process is simplified and electrical performance is improved over typical jacks. The outer jacket diameter may vary from one application to the next, depending on the particular standards in place, for example. Typical maximums are 0.250″ for Unshielded Twisted Pair (UTP) and 0.310″ for Shielded Twisted Pair (STP). 
         [0031]    Wire containment cap  104  shown in  FIGS. 3-7  was generally designed around an IDC terminal layout substantially similar to the IDC terminal layout in  FIG. 8 . However, the techniques for wire pair separation utilized by wire containment cap  104  can be utilized generally to separate wire pairs in communication jacks with a variety of IDC terminal layout arrangements. 
         [0032]      FIG. 9  illustrates diagrams  300  of six alternate IDC terminal layout arrangements along with the corresponding wire containment cap design for each of those arrangements. The diagrams  302 ,  304 ,  306 ,  308 ,  310 , and  312  merely provide examples of different IDC terminal layouts and wire containment cap designs, but these diagrams do not comprise all of the possible design options available. 
         [0033]      FIGS. 10 and 11  illustrate an alternative wire containment cap  400 . In this alternative embodiment, the wire containment cap  400  includes a plurality of wire retainers  402  that each flex to allow a wide range of wire sizes to be inserted and held in place after insertion. A small barb on each of the wire retainers  402  retains the wires so that they may be clipped to remain in position until installation. This allows the same connector assembly to be used for multiple wire sizes, thereby improving ease of installation for the technician. The wire containment cap  400  also includes a plurality of sloped pair splitters  404  that assist in maintaining a constant number of twists on the cable end of a wire pair. Each sloped pair splitter  404  terminates in a relatively sharp edge between neighboring wire retainers  402 . This sharp edge can cut through insulation material holding bonded pairs together, allowing the wires to be placed into the wire retainers  402  without untwisting and pulling the wires apart by hand. 
         [0034]    While certain features and embodiments of the present invention have been described in detail herein, it is to be understood that the invention encompasses all modifications and enhancements within the scope and spirit of the following claims.