Patent Publication Number: US-4648677-A

Title: Electrical connector assembly and method for terminating cable

Description:
The present invention relates to an electrical connector assembly and method for terminating cable, and more particularly to strain relieving the termination and securing contacts in a connector. 
     A previous arrangement for terminating ribbon cable is shown by Asick U.S. Pat. No. 4,153,325 &#34;Method and Connector for Terminating Twisted Pair and Ribbon Cable&#34; and includes a comb-like member wherein an individual conductors thereof are laced to the comb. Such a method could be time consuming and not provide a suitable strain relief arrangement. 
     The present invention includes a multi-contact connector for terminating cable, and in particular, terminating flat ribbon-type cable, the connector assembly including a housing having a bottom mating face, a top terminating face, an array of passages extending between the faces, and an L-shaped contact carried in each passage. In particular, the assembly includes a stuffer/comb having spaced fingers that fills each passage retention ledge, a cover arrangement that strain relieves the termination, and a latch arrangement that secures the strain relieved termination. Each L-shaped contact is acuately angled, notched medially of its ends, and provided with a dimple. After insertion of these contacts into their respective passages from the bottom mating face, the contact is seated on a retention ledge and bears against the passage wall. In one embodiment, the contact terminates in a slot forming a solderless insulation displacing contact. In another embodiment, the contact terminates in a slot which is soldered to a coaxial-type cable. 
     A plastic contact cavity stuffer/comb has its respective fingers inserted into each respective passage from the top terminating face downwardly to fill the passage between the retention ledge and opposite passage wall and individual comb fingers drive against respective of the dimples. The dimples serve to retain the comb in the connector. 
     A strain relief arrangement protects the cable termination from forces tending to disturb the interconnection. In one embodiment, two pairs of a first cover mount over a second cover, the cover pairs then being mounted in a side-by-side relation whereby to form a wire receiving slot between the two cover pairss. In an alternate embodiment a strain relief comb is disposed between a pair of sidewalls with each sidewall captivating discrete coaxial cables in recesses defining the comb, the comb and sidewall assembly forming a cavity above the terminating portions of the contacts with the contacts being soldered to the wires and the cavity being filled with an epoxy to protect the wires. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a multi-contact connector assembly for termination with a flat ribbon cable. 
     FIG. 2 is a section view of the connector assembly shown in FIG. 1 terminating the conductors of a flat ribbon cable. 
     FIG. 3 is an alternate embodiment showing a multi-contact connector assembly for terminating a coaxial-type cable. 
     FIG. 4 is a section view of FIG. 3. 
    
    
     Referring now to the drawings, FIG. 1 shows a multi-contact electrical connector assembly for terminating two multi-conductor flat ribbon cables 74, the assembly including an elongated base member 12 having a bottom mating face 14, a top wire terminating face 16 and a plurality of terminal receiving passages 18 extending between the faces with an L-shaped contact 22 disposed in each respective passage, each passage including a retention ledge 20, and each contact being acutely angled and including a body 24, a first mating end 26 comprising a foot (the bottom of the &#34;L&#34;) and a second mating end 28 comprising a slotted insulation piercing portion extending above the terminating face, a cover arrangement for captivating the cables to strain relieving their termination, and an arrangement for retaining the contacts within the respective passages. The housing has opposite ends 42,44 with each having retention pads 46. 
     The contacts 22 include a notch 30 and a dimple 32, the notch seating on the retention ledge 20 to position the contact within its passage. 
     A contact stuffer comb 34 of dielectric material comprises an elongated rail 36 having a plurality of laterally spaced fingers 38 extending downwardly therefrom, each finger being adapted to be inserted into a contact passage and serving to fill the passageway between the retention ledge and other passagewall. As shown, there are four rows of spaced contact receiving passages and four combs. The contact dimple 32 biases against its associated comb finger 38 with the collective bias force serving to retain the comb in the connector housing. 
     The strain relief arrangement comprises two pairs of covers 52, 62 and 53, 63, each respective pair being adapted to be pressed downwardly onto the terminating face in side-by-side relation whereby to form a slot 72 and to retain a flat wire cable terminated to respective of the contacts. A plurality of latch plates 48 extend upwardly from each end 42, 44 of the base 12, the latch plates for securing the cover members when they have been pressed downwardly about the connector housing, each latch plate 48 including aparatures 50 for fitment into retention pads 46 and resilient tangs 49 for seating onto a shoulder 43 at the end of each cover. The pair of first covers 52, 53 are asymetrically similar (each has its body set closer to the center of the housing when captivated by the latch plate) and each includes an elongated body 54, 55 having a bottom face adapted to be driven downwardly against the cable and profiled with lateral slots 54a, 55a to receive the insulation piercing portions of the contacts. Each opposite end of the cover includes a flange 56, 57 with an inwardly turned lip 58, 59 to define at each end spaced grooves 60, 61 for slidably fitting downwardly about its respective latch plate. The pair of second covers 62, 63 are also asymmetrically similar each has its body set outward from the center of the housing when captivated by the latch plate) and each includes an elongated body 64, 65 adapted to be driven downwardly towards the first cover to sandwich the ribbon cable therebetween and each terminates in a flange at 66, 67 at each opposite end with like inwardly turned lips 68, 69 to define a groove 70, 71 for similarly being forced downwardly about the latch plate. When each first cover is pushed downwardly, the tang on the latch plate engages a shoulder on the cover wherey to secure the cover. When each second cover is pushed downwardly, the latch plate secures it as well in the same way in that a tang on the latch plate engages a shoulder 43 on the cover. When both the pair of first covers and the pair of second covers have been secured, a slot 72 is defined therebetween for passing the cables 74 upwardly. 
     FIG. 2 shows a section view of the connector assembly of FIG. 1 with one flat ribbon cable 74 terminated (the one to the left) and another flat ribbon cable about to be terminated (the one to the right). Further, the coaction between the end of each finger of the combs 34 pressing against respective dimples 32 on the contacts and the filling of the passages 18 to secure the contacts in their passage is shown. To form the strain relieved interconnection, viewing the assembly to the right, the terminable end portion of the flat ribbon cable is forced downwardly onto the insulation displacing portion of the contacts whereby contact is made with respective conductors inside each wire. The first cover 52 is pushed downwardly and engages the latch plate 48 at each opposite end of the housing whereby to compress the cable against the terminating face 16 and to secure the termination. The ribbon cable is then wrapped upwardly and inwardly (to the left) and then perpendicularly upwards. Thereupon, the second cover 62 is pushed downwardly and to cover arrangement requires the cable to form a &#34;P-shaped&#34; threaded relation. This final relation is shown to the right of FIG. 2 with a cover arrangement using covers 53, 63 and a first cable that has been terminated by the contacts. 
     FIG. 3 shows an alternate connector assembly 80 wherein a plurality of slotted contact portions extend upwardly from the terminating face of a connector housing 82, the interior connector housing arrangement using a stuffer comb and contacts described above being the same. A purpose of this assembly would be to strain relieve the individual wires of coaxial cable 76 of the type having a conductor 78 and a drain wire 79. The strain relief arrangement includes a pair of L-shaped sidewalls, and a strain relief cover member 86, the cover including a lateral rib 85 sized to fit a lateral groove 84 on the housing, a flange 87 at each end, a detent 87a in the flange, a pluality of recesses 88, 89 on each side of the cover to receive individual cables and a pair of locating apertures 88a, 89a. The sidewalls include pins 91, 93, and detents at each end, the sidewalls being adapted to come together against the cover 86 and secure individual wires in the recesses. A &#34;J&#34; sectioned clip 94 secures into the detents at each end of the sidewalls and secures the three to the connector housing. 
     FIG. 4 shows a terminated assembly with the coaxial cable wherein the strain relief comb 86 has its rib 85 received in the lateral slot 84 extending along the terminating face of the connector housing, the wires have been disposed within their respective strain relief comb, a drain wire 79 and a conductor 78 soldered to a contact, and the sidewalls secured thereabout. A cavity formed above the terminating face is filled with an epoxy. 
     For assembly, the cable is prepared by exposing the end portions of the center conductor and drain wire and placed at a right angle to the contact. The conductors are placed into the slot in adjacent of the contact paris and soldered thereto. The center strain relief 86 with clips is then positioned about the cables and the &#34;J&#34; clip is heat-staked to the end of each housing to form a molded interference fit therewith. The cavity is filled with an epoxy bond to maintain the soldered termination.