Abstract:
A multi-conductor communications jack where the individual insulated conductors are forced into associated insulation displacing contacts to make a mechanical and electrical joint with the metallic conductor therein by means of an impact tool which also has thereon a cutting edge for severing the portion of the insulated conductor that extends beyond the jack lead frame. The improvement comprising a series of anvils adjacent the frame and insulation displacing contacts to support the insulated conductor and insure a clean cut without injury to the conductor or insulation.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention pertains to communications jacks and the wiring of such jack and more particularly to the termination of individual conductors in associated insulation displacing contacts (“IDC”) of a communications jack and the severing of the excess insulated conductor beyond the lead frame support of such jack.  
           [0003]    2. Description of the Prior Art  
           [0004]    At present individual insulated conductors are terminated in insulation displacing contacts and the portion of the insulated conductor beyond the lead frame support is severed by a cut-off blade on available impact tools. These tools engage the insulated conductor on either side of the IDC slot and force the insulated conductor downwardly into the slot slicing through the insulation, parting it and making electrical and mechanical contact with the metallic conductor therein.  
           [0005]    The tool cutting edge scrubs along the outer surface of the lead frame support and if the edge is sharp and the impact high, the insulated conductor may be cleanly severed. However, if the blade cutting edge is not sharp, the impact is low, the insulation soft and pliable and the metallic conductor soft and ductile, the cut will be anything but sharp. The distortion of the insulated conductor outside of the lead frame support could also cause problems in the IDC slot. The conductor could be cut or thinned making for a poor or little contact. There can be exposed bare conductor ends which could short out other conductors and the like.  
         SUMMARY OF THE INVENTION  
         [0006]    The invention disclosed herein overcomes the difficulties noted above with respect to the described prior art devices by providing a cutting edge to support the insulated conductor to be severed, adjacent the lead frame support and back-up the cutting blade so that a smooth, clean cut can be made, adjacent the lead frame support, to permit the excess insulated conductor to be removed without affecting the quality of the conductor joint at the IDC slot. It is an object of the invention to provide an improved connector which facilitates the removal of any excess portion of a conductor beyond the connector.  
           [0007]    It is another object of the invention to provide an improved connector which provides a support for any excess conductor beyond the connector to facilitate the removal of such excess conductor.  
           [0008]    It is yet another object of the invention to provide an improved connector which provides a support for any excess conductor beyond the connector and provides an anvil for a cutting blade employed to sever such excess conductor.  
           [0009]    Other objects and features of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principles of the invention, and the best mode presently contemplated for carrying them out.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    In the drawings in which similar elements are given similar reference characters:  
         [0011]    [0011]FIG. 1 is an isometric view taken from below and to the left of the object, of communications jack assembly according to the prior art.  
         [0012]    [0012]FIG. 2 is an isometric view of the lead frame contracts of FIG. 1.  
         [0013]    [0013]FIG. 3 is an isometric view of the lead frame carrier of the device of FIG. 1.  
         [0014]    [0014]FIG. 4 is an isometric view of the lead frame contacts of FIG. 2 installed on the lead frame carrier of FIG. 3.  
         [0015]    [0015]FIG. 5 is an isometric view of the lead frame support of the device of FIG. 1.  
         [0016]    [0016]FIG. 6 is an isometric view of the lead frame support of FIG. 5 assembled to the lead frame contacts and lead frame carrier assembly of FIG. 4.  
         [0017]    [0017]FIG. 7 is an isometric view of the body of the device of FIG. 1.  
         [0018]    [0018]FIG. 8 is an isometric view of a stuffer cap for use with the device of FIG. 1.  
         [0019]    [0019]FIG. 9 is a side elevational view of an impact tool to install electrical conductors to the contacts of the device of FIG. 1.  
         [0020]    [0020]FIG. 10 is a fragmentary front elevational view, partly in section, of the device of FIG. 1 with a conductor, being installed to a contact with the tool of FIG. 9.  
         [0021]    [0021]FIG. 11 is an isometric view of a lead frame support constructed in accordance with the concepts of the invention which can be used with the remaining components of the device of FIG. 1.  
         [0022]    [0022]FIG. 12 is an isometric view of the lead frame support of FIG. 11 assembled to the lead frame contacts and lead frame carrier assembly of FIG. 4.  
         [0023]    [0023]FIG. 13 is an isometric view of the assembly of the components of FIG. 12 with a modified body of the type shown in FIG. 7.  
         [0024]    [0024]FIG. 14 is a fragmentary front elevational view, partly in section, of the device of FIG. 13 with a conductor being installed to a contact with the tool of FIG. 9.  
         [0025]    [0025]FIG. 15 is a rear elevational view of the body of FIG. 7.  
         [0026]    [0026]FIG. 16 is a front elevational view of the body of FIG. 7.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0027]    Turning to FIGS.  1  to  10   15  and  16  there is shown a communications jack assembly  20  constructed in accordance with the prior art and an impact tool  18  often used to install insulated conductors thereto. Jack assembly  20  comprises a body  22 , a lead frame carrier  24  and a lead frame support  26 , shown in FIG. 1 and other components not visible in FIG. 1. Body  22  has a deflectable latch  28  which is used to lock jack assembly  20  into a corresponding aperture in a support frame (not shown) as is well known in the art. The latch  28  deflects towards body  22  as the body  22  is in advanced into a support frame aperture from the rear and expands away from body  22  after assembly  20  is properly positioned. Assembly  20  can be removed from the rear of the support frame by deflecting the latch  28  and pulling assembly  20  free of the support frame.  
         [0028]    The contacts  30  (see FIG. 2) are of the insulation displacement type which do not require that the insulation be removed from an insulated conductor before it can be assembled to a contact. Instead each of the contacts  30  is formed with a slot  32  whose walls are sharp. When an insulated conductor (now shown) is forced down the slot  32 , the insulation is severed and displaced in the area of the slot  32  so that the contact arms defining the slot  32  make a good mechanical and electrical contact with the metallic conductor of the insulated conductor. Each of the contacts  30  has a lead  34  formed when the contact  30  is stamped out. The contacts  30  and leads  34  may be connected to runners at one or both ends during manufacture to hold the positions of the contacts  30  until installation upon the lead frame carrier  24  at which time they are removed.  
         [0029]    The lead frame carrier  24  is shown in FIGS. 3 and 4. A number of grooves  40  are formed along the longitudinal axis of carrier  24 . Each of the grooves  40  will receive one of the leads  34  therein. At a first end  42 , the frame is rounded and the free ends of the leads  34  are bent around end  42  to form the contacts  36  of the completed jack assembly  20 . Rails  44  permit the lead frame carrier  24  to be assembled to the body  22  and stops  46  limit insertion of the lead carrier  24  into body  22 . The contacts  30  are bent perpendicularly to leads  34  and are positioned adjacent supports  48 . Each of the supports  48  has a slot  50  which is aligned with contact slot  32  so that access to the contacts is provided.  
         [0030]    Turning now to FIGS. 5 and 6 the lead frame support  26  and its assembly to the lead frame carrier  24  with contacts  30  assembled thereto are described. Lead frame support  26 , which is mounted over carrier  24  has a base  62  the underside of which contains a support foot  64  which may engage a support surface (not shown). Projecting upwardly from base  62  are two, parallel, spaced apart side walls  66  which have a series of slots  74  positioned along their length. A series of ribs  70 , having enlargements  72  adjacent base  62  fit into the channels  52  between the supports  48  of the lead frame carrier  24 . The ribs  70  guide the lead frame support  60  along channels  52 , and the enlargements  72  lock the support  26  to the carrier  24  by engaging the side walls of the channels  52 . The of slots  74 , in both side walls, are aligned with the positions of the contact slots  32  to permit access to the contact slots  32 . Thus the slots  50  in supports  48  of lead frame carrier  24 , slots  32  in contacts  30  and slots  74  in walls  66  of the lead frame support  26  are all aligned and an electrical conductor can be supported therein. The insulation can be received in slots  50  and  74  and the central conductor received in the slot  32  of contact  30 . At the ends of some of the fingers  76  formed by slots  74  in side walls  66  are locking tabs  78  and further locking tabs  80  appear on both side walls  66 . The functions of these tabs will be described below.  
         [0031]    [0031]FIGS. 7, 15 and  16  show body  22  which is assembled to the sub assembly of FIG. 6,, as shown in FIG. 1. An aperture  90  is generally rectangular to accept the lead frame carrier  24  adjacent end  42 . Side slots  92  communicating with aperture  90  are shaped to receive rails  44  of carrier  24 . Slots  94  receive the contacts  36  adjacent the plug aperture  96  in the front face of body  22  as shown in FIG. 16. Slots  98  on flexible arms  100  provide shoulders  102  to engage the flat back surfaces  83  of locking tabs  80 . The arms  100  are deflected outwardly as inclined front face  81  of tabs  80  engage such arms  100  as the lead frame support  26  is advanced within body  22 . Once the tabs  80  enter slots  98 , the arms  100  return to the position as shown in FIG. 1 to retain the body  22  and lead frame support  26  in assembly.  
         [0032]    The individual conductors of a cable to be terminated can be placed in the slots of the jack assembly  20  and terminated by means of a stuffer cap  110  shown in FIG. 8. Stuffer cap  110  has a base  112  and two depending, parallel, spaced apart, side walls  114 . Along the interior surface of base  112  and walls  114  are a front wall  116  and a rear wall  118  (mostly hidden in FIG. 8). Front wall  116  has a central rectangular recess  120  and two slots  122  so as to describe two narrow fingers  124  and  126  adjacent the side walls  114 . The rear wall  118  is similar to front wall  116 .  
         [0033]    When the stuffer cap  110  is positioned on lead frame support  26 , the outer fingers  124  enter slots  74  in side walls  66  of support  26 , the inner fingers  126  enter slots  50  in supports  48  of lead frame carrier  24  and the slots  122  are positioned over the ends of the contacts  30 . If an insulated electrical conductor (not shown) is positioned across contact  30  and in slots  74  and  50  and stuffer cap  110  is pushed downwardly towards the base  62  of lead frame support  26 , then the conductor insulation will be severed and displaced and contact will be established between contact  30  and the central metallic conductor.  
         [0034]    However, in order for the stuffer caps  110  to operate properly, any excess insulated conductor beyond side wall  66  of support  26  must be removed first. The presence of the excess conductor will bow side walls  1   14  of stuffer caps  110  and prevent its proper seating.  
         [0035]    Since there are four fingers  124  and four fingers  126 , four conductors could be terminated at the same time. But because of the sizes of the parts involved and the need to control four separate conductors the termination of all four conductors at the same time is quite difficult.  
         [0036]    Although not shown a small cross member is placed between front wall  116  and rear wall  118  on the interior surface of each of the side walls  114  to act as a catch for the locking tabs  78  of fingers  76  of lead frame  26 . This locking action insures that the insulated conductor is fully inserted into slots  32  of contacts  30 . If insulated conductors are installed using stuffer cap  110 , one at a time, the cap  110  must be released to gain access to the other contacts  30  under stuffer cap  110 . This is done by expanding side walls  114  away from the lead frame support  26  and pulling stuffer cap  110  upwardly away from lead frame support  26 . The stuffer cap  110  can also be applied to lead frame support  26  after all of the conductors are properly seated in slots  32  of contacts  30 . This provides strain relief to the conductor on both sides of contact  30 , prevents unintentional access and acts as an environmental seal against dirt and other contaminants.  
         [0037]    Because the insulated conductors have small external diameters, and the space to work in is small and because it is difficult to align the conductors with the slots  32 ,  50  and  74  especially when the conductor can not extend beyond the side wall  66  of support  26 , while aligning the stuffer cap  1   10  with these same slots resort is had to various hand tools to install the insulated conductors in the slots  32  of contacts  30  and cut-off the excess insulated conductor beyond the side wall  66  of support  26 . One such tool is shown in FIG. 9. The tool  140  is an impact tool having a compression spring (not shown) in its handle  142 . The spring is connected to a plunger  144  which is forced into handle  142  by the punch-down bit or punch-down implement, to be described, until a settable predetermined value is reached. The implement is forced against the work piece with a force corresponding to the predetermined value.  
         [0038]    The implement  146  has a first pushing portion  148  which engages the conductors between the supports  48 , a second pushing portion  150  which engages the portion of the conductor in slot  50  in support  48  of lead frame carrier  24  and a recess  152  which can accommodate the upper portion of the contact  30  to permit the pushing portions maxim conductor contact. A further pushing portion  154  engages the conductor in slot  74  in side wall  66  of lead frame support  26 . The final portion of implement  146  is cut-off blade  156  which extends from a cutting edge  158  below the level of the remaining portions of implement  146  and along an inclined face  160 .  
         [0039]    The operation of tool  140  to install a conductor  170  to jack assembly  20  is shown in FIG. 10. Eight insulated conductors  170  are positioned between supports  48  of carrier  24  and fanned out, one adjacent each of the eight contacts as shown by insulated conductor  170   a . The conductor  170   a  is manually pushed part way into slot  32  of contact  30  with a tail  174  extending beyond wall  66 . The tool  140  is aligned with the contact such that pushing portion  150  enters slot  50 , pushing portion  154  enters slot  74 , the upper portion of contact  30  enters slot  150  and the cutting edge  158  of blade  156  engages conductor  170   a.  As the implement  146  moves downwardly in FIG. 10, pushing portion  148  engages insulated conductor  170   a  to provide strain relief for the conductor  170   a  as installation is completed so as to minimize any stretching of the conductor or its insulation as the insulated conductor  170   a  is forced into slot  32  of contact  30 . The cut-off blade  156  severs tail  174  from insulated conductor  170   a  and the tail  174  falls free of the jack assembly  20 . After all of the insulated conductors  170  are installed stuffer cap  110  is added and the installation is complete. The concept is that if a sharp cutting blade is operated at a high rate of speed, the insulated conductor tail  174  can be clearly severed from the remainder of the insulated conductor  170   a  which will be stiff enough to allow cut-off without any further support for the insulated conductor  170   a.    
         [0040]    The foregoing sequence may well apply to situations where the blade  156  cutting edge  158  is sharp, the blade  156  is precisely positioned with respect to wall  66  and a high impact force employed. However, if cutting edge  158  is not sharp, or if blade  156  is not closely positioned to wall  66 , if the conductor insulation has a high modulus of elasticity or the metallic conductor is very ductile the blade may not sever the tail  174  from the remainder of insulated conductor  170   a.  The insulated conductor  170   a  could be bent along wall  66  in which state it would prevent installation of the stuffer cap  110 . The insulation of the conductor could be removed leaving a bare metallic conductor which could cause shorts to other in conductors, or the insulated conductor  170   a  could be broken at slot  32  of contact  30  making a poor contact with conductor  170   a  or no contact at all.  
         [0041]    Turning now to FIGS.  11  to  14  there is shown a snap-in jack assembly  200  constructed in accordance with the invention. FIG. 11 shows a lead frame support  226  employed with assembly  200 . The outer walls  266  have been modified to add a series of anvils. Anvil  228  is adjacent the base of slot  74   a,  anvil  230  is adjacent the bases of slots  74   b  and  74   c  while anvil  232  is adjacent the base of slot  74   d . The opposite side wall  266 , not visible in FIG. 11 has a similar arrangement to that described so that there is an anvil at the base of each of the eight contacts of jack assembly  200 .  
         [0042]    The latch between the lead frame support  226  and the body  222  is altered because the flexible arms can not extend about the entire locking latch  80  as is done with flexible arms  100  of jack assembly  20  of FIG. 1. Instead, locking arm  238  is made up of a first portion  240  which extends along the longitudinal axis and a second portion  242  perpendicular thereto. Inner surface  244  of second portion  242  engages the rear surface  83  of locking tab  80  to hold in assembly the components of jack assembly  226 . The leading edge  81  of locking tab  80  forces locking arm  238  away from the body  222 , but once the rear surface  83  is adjacent inner surface  244 , the locking arm  238  returns to its initial position with inner surface  244  now engaging rear surface  83 .  
         [0043]    Turning now to FIG. 14 the manner of installing insulated conductors  170  to the improved jack assembly  226  is shown. The lead frame carrier  24 , the contacts  30  and the tool  140  remain the same. The significant change made is the addition of the anvils  228 ,  230  and  232  to the lead frame support  226 . In FIG. 14, it is assumed that insulated conductor  170   a  has been routed between the supports  48  and into a slot  50  in a support  48  of lead frame carrier  24 . The insulated conductor  170   a  is then guided into slot  32  of contact  30  and through slot  74   c  of lead frame support  226 , over anvil  230  and extending beyond side wall  266  of support  226 . As above described, the insulated conductor  170   a  is first manually pushed into slot  32  of contact  30 . The tool  140  is pushed downwardly in FIG. 14 so that pushing portion  150  enters slot  50 , pushing portion  154  enters slot  74 , the upper portion of contact  30  enters slot  150  and the cutting edge  158  of blade  156  engages conductor  170   a.  Because of the presence of anvil  230  to support and back-up the insulated conductor  170   a,  a clean cut can be achieved and tail  174  is severed as the blade  156  advances to anvil  230  through insulated conductor  170   a.    
         [0044]    While there have been shown and described and pointed out the fundamental novel features of the invention as applied to the preferred embodiment; it will be understood that various omissions and substitutions and changes of the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention.