AN ELECTRICAL CONNECTOR AND WIRE ASSEMBLY METHOD

Abstract: Discrete wires are unraveled from a bundle of wires and assembled in respective passageways (12) in an electrical connector housing (11) by preloading the wires into a wire holder (21) which locates the leading ends of the wires at the same pitch as the passageways (12) but in staggered relation. The wire holder (21), supported by the wires, is then inserted into and along a mouth (14) of the housing (11) until it abuts a tapering throat (13) at the entrance to the passageways (12). Further advance of the bundle feeds the discrete wires through the wire holder (21) into the respective passageways (12) guided by the throat (13).

Description: AN ELECTRICAL CONNECTOR AND WI RE ASSEMBLY METHOD The invention relates to an electrical connector and to a method of assembling discrete wires of a series of discrete wires in an electrical connector housing. A known type of connector housing is formed with a wire receiving duct extending rearwardly from a portion adjacent a contact face and opening at a wire receiving mouth at a rear face, a row of closely spaced contacts being received in respective cavities at the contact face which cavities extend transversely of and communicate with the duct portion. Flat cable, in which a series of wire-like conductors are located in side-by-side relation at the same pitch as the passageways by webs of insulation, may readily be assembled in the housing for termination , by insertion of a free end into and along the duct so that the conductors are aligned with respective contacts. The contacts are then driven into engagement with respective conductors and a rear portion of the housing adjacent the mouth crimped into engagement with the cable to provide strain relief. An example of such connector is described in U .S. Patent Application No. 423 ,486. However, a problem arises, particularly in the field , when it is desired to assemble and terminate discrete wires extending from a bundle of wires in the housing. The discrete wires cannot readily be maintained in the desired serial positions and at the correct pitch during insertion into the connector whe unraveled from the bundle. According to one aspect of the invention there is provided a method of assembling and terminating discrete wires of a series of wires extending from a bundle in an electrical connector of the type comprising an insulating housing having a wire receiving duct extending rearwardly from a portion adjacent a contact face and opening at a wire receiving mouth , a a rear face , a row of closely spaced contacts received in respective cavities at the contact face which cavities extend transversely of an communicate with the duct portion , in which method the wires are inserted through the mouth into and along the duct into alignment with the contact and the contacts urged into the duct into terminating engagement with the wires, characterized by the step of loading the discrete wires into respective wire locating apertures of a wire holder to form a subassembly prior to insertion of the wires into the duct which apertures are located at the same pitch as the contacts, inserting the subassembly into and along the duct, thereby to bring the discrete wires into alignment with respective contacts. Preferably, when used in a connector in which the duct portion communicates with an enlarged mouth through a common, divergent wire guiding throat, the subassembly is inserted axiaily along the duct until the wire holder is arrested by interference with the throat and the wires are then advanced through the holder into the duct portion located at the same pitch as the contacts. The wire holder retains the discrete wires at the same pitch as the contacts enabling rapid and accurate termination simply by pushing the cable manually. According to another aspect of the invention , there is provided an electrical connector comprising an insulating housing having a wire receiving duct extending rearwardly from a portion adjacent a contact face and opening at a wire receiving mouth at a rear face, a row of closely spaced contacts received in respective cavities at the contact face which cavities extend transversely of and communicate with the duct portion , a series of discrete wires extending from a bundle and inserted into the duct throught the mouth along the duct to the duct portion into engagement with the wires, characterized in that, the discrete wires are located in wire locating apertures of a wire holder received as a sliding fit in the duct, such apertures being at the same pitch as the contacts. The housing may include a clamping portion deformed into gripping engagement with the wire behind the wire holder to provide strain relief and retaining the wire holder in the housing duct. Desirably, the apertures open towards the contacts and are in staggered relation with adjacent apertures being located in different rows. This both enables the discrete wires to be maintained at the same close pitch as the contacts and the apertures to be defined by adjacent wall porttons in a .comb-like structure in spite of the close pitch. Advantageously, the wires are loaded into the wire holder at locations spaced from their free ends, the free ends trimmed to lengths correspondiπg to axial lengths of the passageways and throat, and the wire holder then slid along the wires to the free ends. This ensures that the wires are trimmed to the correct length so that they all extend sufficiently along the cavities for effective termination in the final axial position of the wire holder relative to the cable. The apertures may open to only one or both sides of the wire holder providing comb-like structures which facilitate entry of the wires in the holder. Preferably , the slots have resilient wire entry portions of reduced width securely to retain the wires in the apertures throughout the loading step. According to another aspect of the invention , there is provided an electrical connector kit comprise an insulating housing having a wire receiving duct extending rearwardly from a portion adjacent a contact face and opening at a wire receiving mouth at a rear face; a row of closely spaced contact receiving cavities at the contact face communicating with the duct portions; a row of contacts received in respective cavities; characterized by a wire holder having a row of wire locating apertures at the same pitch as the contacts , the wire holder being insertable into the duct mouth when loaded with a series of discrete wires extending from a bundle of wires to bring the discrete wires into alignment with respective contacts. Preferably, the duct portion located adjacent the contact face, communicates with an enlarged mouth through a divergent throat of smaller size that the wire holder, and the wire locating apertures receive the wires in a sliding fit, movement of the wire holder being along the duct being arrested by abutment with the throat. An example of the invention will now be described with reference to the accompanying drawings in which : FIGURE 1 is an isometric view of a known electrical connector in which wires can be terminated according to the method of the invention ; FIGURE 2 is a cross-sectional view of the connector of Figure 1 ; FIGURE 3 is a cross-sectional view along line 3-3 of Figure 2; FIGURE 4 is a rear view of the connector; FIGURE 5 is an isometric view of a wire holder according to the invention; FIGURES 6a and 6b are isometric views of first and second steps of loading discrete wires into the wire holder; and FIGURES 7a through 7d are isometric views showing successive steps of loading a subassembly of the wire holder and wires into the connector and termination of the wires. As shown particularly in Figures 1 through 4, a connector suitable for use in the invention is similar to that used for ribbon cable and disclosed in U. S. Patent Application No. 423,486, the disclosure of which is incorporated herein by reference. Briefly described, the connector comprises a housing 11 moulded in one piece of suitable plastics material formed with duct comprising a single row of blind ended wire receiving passageways 12 extending rearwardly from a location adjacent a contact face and communicating through a common, divergent, wire guiding throat 13 with a wire receiving mouth 14 of increased size. Lateral walls 15 between adjacent passageways 12 are perforate (for receipt of the insulating web extending between conductors when used with the ribbon cable) passageways and conductor supporting rails 16 extend along the floor of each passageway. Contact receiving cavities 17 at the contact face communicate with the passageways and insulation piercing contacts 18 are preloaded in the cavities for termination with the respective conductors in the passageways. Deformabie cable clamping latches 19 are formed in a wall of the- mouth, for deformation into the mouth into clamping engagement with a cable terminated in the connector. A wire holder 21 is moulded in one piece of plastics material with a series of staggered wire locating apertures 22 located at the same pitch as the passageways 12 but in two rows 23 and 24, having centrelines on^ opposite sides of the centreline of the passageways, adjacent apertures being in different rows. The apertures open to a common side of the wire holder providing a resilient comb-like structure, walls of the apertures constituting teeth. Wire entry portions 25 of each aperture are of reduced width securely to retain wires in the holder. The overall size of the wire holder is such that it is receivable as a sliding fit in the mouth 14. In order to assemble ends of discrete wires of a bundle of wires in a shielded cable , the outer insulating jacket is stripped adjacent the end to expose the foil shield which is returned over the jacket. The discrete wires are then unraveled and drawn laterally into the holder in their desired serial position with the holder spaced from the leading edges as shown in Figure 6A. The ends of the discrete wires are then trimmed so that their leading edges are of lengths corresponding to the axial lengths of the passageway plus the axial length of the throat. The wire holder is then slid along the wires to a location adjacent their leading ends thereby holding the leading ends in a fixed position (Figure 6B) . The subassembly is then inserted into the mouth (Figure 7A) and advanced by pushing the cable until the wire holder abuts the throat (Figure 7B ) when the discrete wires will be advanced through the wire holder guided by the throat into respective passageways as shown in Figure 7C. The contacts 18 are then driven against the wires in known manner and the clamping portion deformed into engagement with the wires behind the wire holder to assist in providing strain relief (Figure 7D) . It will be appreciated that the location of the centrelines of the rows of apertures 23, 24 equidistant from the centreline of the passageway permits the leading ends of the wires to be guided by the throat into the passageways with minimum deviation. The resiliency of the aperture walls or teeth of the comb-like wire holder adjacent the wire entry ends of the wire holder apertures enables the wires to be loaded therein one-by-one and securely retained therein while remaining wires are manipulated into a desired position .

Claims: WHAT IS CLAIMED; 1 . An electrical connector comprising an insulating housing ( 11 ) having a wire receiving duct (12, 13 , 1 ) extending rearwardly from a portion (12) adjacent a contact face and opening at a wire receiving mouth (14) at a rear face, a row of closely spaced contacts (18) received in respective cavities (17) at the contact face which cavities (17) extend transversely of and communicate with the duct portion (12) , a series of discrete wires extending from a bundle and inserted into the duct (12, 13, 14) through the mouth (14) along the duct to the duct portion (12) where they are terminated by respective contacts (18) urged into the duct portion (12) into engagement with the wires, ' characterized in that, the discrete wires are located in wire locating apertures (22) of a wire holder (21 ) received as a sliding fit in the duct (12 , 13 , 14) , such apertures (22) being at the same pitch as the contacts (18) . 2. An electrical connector according to claim 1 , characterized in that, the wire locating apertures (22) open towards the contact face. 3. An electrical connector according to claim 1 and claim 2, characterized in that, the housing (11 ) comprises a clamping portion (19) deformed into engagement with the wires at a location between the rear face and the wire holder (21 ) . 4.. An electrical connector t according to any one of the preceding claims characterized in that the discrete wires are located in the wire locating apertures (22) in a sliding fit. 5. An electrical connector, according to claim 4 characterized in that, the duct portion ( 12) is divided into a row of individual wire receiving passageways which communicate with the mouth through a common , divergent wire guiding throat (13) , the wire locating apertures (22) being in staggered relation with adjacent apertures being in different rows (23 , 24) . 6. An electrical connector according to claim 5 , characterized in that the rows (23 , 24) of apertures (22) are arranged on opposite sides of the row of passageways (12) . 7. A method of assembling and terminating discrete wires of a series of wires extending from a bundle electrical connector of the type comprising an insulating housing (11 ) having a wire receiving duct (12, 13, 14) extending rearwardly from a portion ( 12) adjacent a contact face and opening at a wire receiving mouth (14) , at a rear faςe, a row of closely spaced contacts (18) received in respective cavities (17) at the contact face which cavities (17) extend transversely of and communicate with the duct portion (12) , in which method the wires are inserted through the mouth ( 14) into and along the duct (12, 13 , 14) into alignment with the contacts (18) and the contacts (18) urged into the duct (12, 13, 14) into terminating engagement with the wires , characterized by the step of loading the discrete wires into respective wire locating apertures (22) of a wire holder (21 ) to form a subassembly prior to insertion of the wires into the duct which apertures (22) are located at the same pitch as the contacts (18) , inserting the subassembly into and along the duct, (12 13 , 14) thereby to bring the discrete wires into alignment with respective contacts (18) . 8. A method according to claim 7 for use in a connector in which the duct portion ( 12) communicates with an enlarged mouth (14) through a common , divergent wire guiding throat (13) , characterized in that the subassembly is inserted axially along the duct (14) until the wire holder (21 ) is arrested by interference with the throat (13) and the wires are then advanced through the holder (21 ) into the duct portion (12) located at the same pitch as the contacts. 9. An electrical connector kit comprising an insulating housing (11 ) having a wire receiving duct ( 12 , 13 , 14) extending rearwardly from a portion (12) adjacent a contact face and opening at a wire receiving mouth (14) at a rear face; a row of closely spaced contact receiving cavities (17) at the contact face communicating with the duct portions (12) ; a row of contacts (18) received in respective cavities (17) ; characterized by a wire holder (21 ) having a row of wire locating apertures (22) at the same pitch as the contacts (18) , the wire holder (21 ) being insertable into the duct mouth ( 14) when loaded with a series of discrete wires extending from a bundle of wires to bring the discrete wires into alignment with respective contacts (18) . 10. An electrical connector kit, according to claim 9 characterized in that, the wire locating apertures (22) open to a side of the wire holder (21 ) towards the contacts (18) . 1 1 . An electrical connector kit according to claim 9 or 10 characterized in that, the wire locating apertures (22) are located in staggered relation with adjacent apertures being in different rows (23, 24) . 12. An electrical connector kit according to any one of claims 9 to 11 characterized in that the duct portion (12) , located adjacent the contact face, communicates with an enlarged mouth ( 14) through a divergent throat (13) of smaller size that the wire holder (21 ) , and the wire locating apertures (22) receive the wires in a sliding fit, movement of the wire holder (21 ) being along the duct being arrested by abutment with the throat ( 13) .

Inventors: COLDREN DANIEL RUSSELL, DAVIS WAYNE SAMUEL, FORTUNA JON ALAN, COLDREN, DANIEL, RUSSELL, DAVIS, WAYNE, SAMUEL, FORTUNA, JON, ALAN
Applicants: AMP INC, AMP INCORPORATED
Application year: 1985
Main classification: H01R13
IPC codes: H01R4, H01R13, H01R43