Patent Publication Number: US-4648679-A

Title: Connector assembly for mass termination

Description:
This invention relates to a connector assembly for mass terminating conductors into respective terminals and, in particular, to an arrangement for strain relieving the terminated conductors. 
     There is a constant need to provide more efficient and cost productive methods for mass terminating multiple conductors in a single operation. It is not always cost efficient to crimp individual terminals on individual conductors and then individually load the terminated conductors into restrictive cavities in a housing. It is known to provide a connector assembly that includes a housing and a plurality of insulation displacement terminals, the housing having a plurality of terminal passages that are enclosed but open onto a front mating face and are open and accessible adjacent the rear face whereat a wire may be stuffed downwardly and into an insulation displacing slot of each respective terminal. In U.S. Pat. No. 4,243,288 &#34;Connector Assembly for Mass Termination&#34; issuing Jan. 6, 1981 to Lucius et al, a pair of conductor engaging ears are deformed downwardly and about the wire to nonreleasably strain relieve the termination between the wire in the terminal. While possibly suitable for the uses intended, such an operation requires apparatus for bending the ears. It would be desirable to have a connector assembly including terminals which do not require special metal deforming dies and special apparatus for strain relieving the mass terminated assembly. 
     The present invention provides an electrical connector assembly for mass terminating each of a plurality of insulated wires with a respective plurality of conductive solderless terminals, the connector including a dielectric housing having a plurality of passages extending in a single row from a rear face through the housing to open on the mating face, each of the passages receiving a terminal and being openly accessible at the rear face remote from the mating face. Each terminal is U-shaped and axially spaces a wire restraint portion from an insulation displacement portion, each portion being disposed within the openly accessible portion of the housing. 
     In accordance with this invention, the solderless terminal for electrically and mechanically terminating the insulated wire is characterized by a U-shaped channel including a wire retention portion comprising a constricted wire receiving opening having wire engaging means formed integrally therewith and means to compress the wire engaging means into engagement with a longitudinally extending circumferential portion of the wire and to maintain that engagement. The means to compress comprises the channel including a base having a pair of longitudinally extending sidewalls resiliently connected thereto, and the wire engaging means comprises a pair of ribs each extending laterally towards the other from one respective sidewall and dovetailing downwardly towards the base to form the constricted wire receiving opening, the sidewalls being laterally spaced apart by an amount substantially that defined by the outer periphery of the wire and each rib including an engagement surface which faces the base and which is adapted to engage the outer periphery of the wire inserted downwardly between the ribs. 
     Advantageously, such a wire restraint will resist angular forces placed onto the wire and which will disturb the wire termination within the insulation displacement portion. 
    
    
     The invention will now be described, by way of example, with reference to the accompanying drawings in which: 
     FIG. 1 is an exploded perspective view of the subject electrical connector assembly. 
     FIG. 2 is an end view in section, such as would be seen taken along lines 2--2 of FIG. 1, of the electrical connector assembly in a fully assembled condition. 
     FIGS. 3-5 are, respectively, partial top, partial side, and end views of the solderless terminal of FIG. 1 according to the present invention. 
     FIG. 6 is a view in section of a solderless terminal captivating a wire. 
     FIGS. 7-9 are, respectively, partial top, partial side, and end views of the solderless terminal shown in FIG. 6. 
    
    
     Referring now to the drawings, FIG. 1 illustrates an electrical connector assembly 100 including a housing 16 having a plurality of solderless terminals 30 mounted in the housing each for cutting through the wire insulation 14 of a wire 10 and terminating the respective conductor 12. The housing 16 is an elongated member of rigid plastics having a plurality of terminal passages 26 that are enclosed at the forward end portion of the housing and open onto a mating front face 18 and are open and accessible adjacent the rear face 20, the passages being channel shaped to receive a wire stuffed downwardly therein. Barriers 22 having top edges 24 and inward ledges 28 define the open channels adjacent the rear face. 
     Each terminal 30 is integrally formed and includes a forward mating end (not shown) which is disposed in the forward end portion of the enclosed housing passage, a U-shaped insulation displacing portion formed by a pair of panels 34 upstanding from a base 32 whereby to define a wire receiving channel therebetween, and an arrangement including a pair of sidewalls 40 for captivating a wire. A flange 36 extends inwardly from the opposite ends of each panel with the opposing pairs of flanges at each end defining an insulation piercing slot 38 therebetween. 
     Spaced axially rearward from the insulation displacement portion as a continuation of the base 32 is the wire restraint which includes the pair of upstanding longitudinally extending sidewalls 40 each being resiliently connected to the base and having a rib 42 stamped and formed inwardly therefrom, each rib confronting and cooperating to define a constricted throat overhanging the base 32 of the terminal for captivating a longitudinal end portion of the wire inserted therebetween, inward distal end portions of the ribs being spaced apart by an amount less than that defining the outer diameter of the wire received therebetween. 
     FIG. 2 shows, in section, an end view of the housing 16 with a plurality of terminals 30 being disposed in their respective channels and each captivating a wire 10. A pair of open channel shaped portions dispose the wire end portions and their associated terminals in each of two parallel rows, each set of channels upstanding from a common base 23. Each channel portion is U-shaped and comprises the base 23, the barriers 22 extending upwardly from the base with adjacent pairs of respective barriers on the housing forming the channels, and barriers terminating in longitudinal edges 24 and each adjacent confronting pair including an inwardly extending ledge 28. 
     The wire restraint ribs 42 are stamped and formed from each respective sidewall 40 and extend downwardly and inwardly from the free edge towards the base 32 to form a longitudinal portion 43 which engages the outer periphery of the wire insulation. The top edge 41 of each sidewall 40 is disposed adjacent to the bottom face 27 of its respective ledge 28 to captivate the terminal 30 at the rear end. Each ledge is chamfered to improve the function of the throat for receiving the wire. 
     FIGS. 3-5 show additional detail of the terminal 30. 
     FIG. 3 shows each rib 42 extending inwardly from its respective sidewall 40 and spaced axially from the insulation displacement portion, the ribs forming confronting nose-shaped protuberances. 
     FIG. 4 shows the rib 42 stamped from its respective sidewall 40 and forming the longitudinal portion 43 facing the base 32 for abutting a longitudinal portion of the wire&#39;s outer periphery. 
     FIG. 5 shows an end view of the terminal 30 and the wire engaging ribs 42 extending towards one another. 
     FIG. 6 shows an alternate wire captivating construction as comprising a pair of sidewalls 50 each extending upwardly from its base 52, reversely bent so as to curve inwardly and outwardly relative to its sidewall to form a Vee-shaped portion with the apex of the two Vees being coplanar and disposed in a plane parallel to the base 52. The inward extension of each Vee forms a wire receiving throat or constriction. The distal longitudinal edges 51 of the sidewalls 50 are adjacent to the downwardly facing surface 27 of the ledge 28 captivating the terminal. 
     FIGS. 7-9 show additional detail of the terminal shown in FIG. 6. FIGS. 7 and 8 show that the wire captivating portion is longitudinally extending and comprises respective pairs of wire engaging Vee portions, each Vee overhanging the terminal base. FIG. 9 shows the reversely bent Vees. 
     A wire inserted into the terminal throat passes through the constriction and is resiliently captivated in the recess formed between the base of the terminal and the bottom engagement surface of the wire engaging ribs or Vee portions. The sidewalls are resilient, are not deformed as a result of wire captivation, and cooperate to bias the ribs or Vee portions against the outer periphery of the wire insulation. The sidewalls elastically yield in lateral directions and do not undergo permanent shape change upon receipt or upon removal of a wire. The resiliency of the sidewalls serves to compress the wire engaging ribs or Vee portions into engagement with the wire insulation.