EP0009867A1

EP0009867A1 - An electrical plug receptacle connector and a method of manufacturing such a connector

Info

Publication number: EP0009867A1
Application number: EP79301574A
Authority: EP
Inventors: Donald Wayne Kent Hughes; Robert James Kobler; Ronald William Myers
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1978-09-08
Filing date: 1979-08-03
Publication date: 1980-04-16
Also published as: FI67458B; NO792814L; DK158182B; DK158182C; AR218161A1; EP0009867B1; HK4485A; AU4997579A; NO154364C; CA1101957A; FI67458C; SG45084G; DK374179A; ES483993A1; AU523952B2; FI792753A; MX146588A; BR7905491A; DE2964098D1; NO154364B

Abstract

An electrical plug receptacle connector and a method of manufacturing such a connector.

A receptacle connector (2) comprises an insulating housing (6) having an opening (12) for receiving a plug (68), contact springs (58) on contacts (52b) in the housing (6) extending obliquely across the opening (12) for engaging the contacts (not shown) on the underside of the plug (68). Each contact (52b) comprises a flat strip of metal and lies in a channel (46b) in the housing (6), a tail portion (60b) of the contact (52b) extending from the housing (6) through a hole in a printed circuit board (4), the contacts (52b) being retained by barbs (62b) thereon in the channels (46b). According to the method of manufacturing the receptacle connector, contacts (52b) are applied to the housing (6) simultaneously, in the form of juxtaposed rectilinear metal strips (not shown) joined by carrier strips, the rectilinear strips being then bent to shape by means of tooling (not shown) in co-operation with the housing (6).

Description

This invention relates to an electrical plug receptacle connector and to a method of manufacturing such a connector.
There is disclosed in United States Patent Specification No. 3,850,497, an electrical plug receptacle connector comprising an insulating housing having a plug-receiving end and a rearward end, a plug-receiving opening extending into the plug-receiving end, such opening having opposed internal side walls and opposed internal end walls, the housing having opposed external side walls and opposed external end walls, a plurality of electrical contacts arranged in juxtaposed spaced relationship, each comprising a contact spring portion extending from one of the internal side walls at a position adjacent to the plug-receiving end, obliquely into the opening and towards the opposite internal side wall, and each contact having a portion extending from the plug-receiving end through the housing between the one internal side wall and the adjacent external side wall and towards the rearward end of the housing, the plug-receiving opening being dimensioned to receive an electrical plug connector having spaced contact members therein for engaging the contact spring portions of the contacts of the receptacle connector.
The plug connector is described in detail in United States Patent Specification No. 3,860,316, for example.
Although this known receptacle connector is widely used in the telephone industry, it is being used to an increasing extent on equipment other than telephone equipment, for example, data processing equipment which may be installed adjacent to a telephone exchange, small computers and similar equipment.
It is a disadvantage of the known receptacle connector that the contacts are in the form of circular cross-section wire springs constituting the contact spring portions of the contacts and being connected to lead wires by means of ferrules crimped to the leads and to the wire springs to splice them together, the ferrules being lodged in individual bores formed in the housing between the one internal side wall and the adjacent external side wall. The manufacture of the known receptacle connector must therefore include the steps of crimping the ferrules to the wire springs and the lead wires, and of then inserting the individual ferrules into the bores. It is another disadvantage of the known receptacle connector that it is unadapted for mounting on a printed circuit panel as would be desirable for example where the receptacle connector is to be used in data processing equipment. Although the wire springs, which make only line contact with the contact members of the plug connector, are suitable for the transmission of audio frequency signals, larger areas of c6ntact between the contact portions of the receptacle connector contacts and the contact members of the plug connector would be desirable in the case of the more recent applications, mentioned above, of the receptacle connector.
The present invention is intended to provide a plug receptacle connector which is easier and thus more economical to manufacture than the known receptacle connector described above and which is also more versatile in respect of its fields of use.
According to one aspect of the present invention, an electrical receptacle plug connector as defined in the second paragraph of this specification is characterised in that each of the contacts has been formed from a.single elongate, flat, strip of metal, an intermediate portion of such strip being disposed in a contact-receiving channel extending from the plug-receiving end of the housing towards the rearward end thereof, a portion of the strip extending from one end of the intermediate portion, having been bent back over a portion of the plug-receiving end between the one internal side wall and the adjacent external side wall, to provide the contact spring portion, a tail portion of the strip extending from the other end of the intermediate portion and beyond the housing, projections extending laterally from the strip providing mechanical interference connections between the contacts and the housing to maintain the contacts in assembled relationship to the housing.
According to another aspect of the present invention, a method of manufacturing'an electrical plug receptacle connector as defined in the second paragraph of this specification, is characterised by the steps of arranging a series of elongate metal strips connected together in juxtaposed relationship, so that an intermediate portion of each strip is disposed in a contact-receiving channel extending from the plug-receiving end of the housing towards the rearward end thereof, with one end portion of each strip projecting beyond the plug-receiving end of the housing and the opposite end portion of each strip projecting beyond the rearward end of the housing, and employing tooling to bend, in co-operation with a first edge portion of the plug-receiving end between the one internal side wall and the adjacent external side wall, the one end portion of each strip back from the plug-receiving end of the housing to cause such portion to extend obliquely into the plug-receiving opening and to bend the opposite end portion of the strip, so that at least one extremity of such portion projects outwardly of the housing, the method also including the steps of severing the connections between the metal strips and producing an interference mechanical connection between a lateral projection on each strip, and the housing, to retain the strips in assembled relationship to the housing.
According to embodiments of the present invention, which are described in detail below, the receptacle connector is adapted specifically for domestic use in that it is so arranged that the plug connector cannot easily be extracted from the plug-receiving opening, for example by a small child, and in that it is so arranged that a small ychild's finger cannot be impaled upon the free ends of the contact portions of the contact springs.
The state of the art is further exemplified by United States Patent Specifications Nos. 4,071,696, 3,444,329, 3,369,214 and T958,009.
For a better understanding of the invention, embodiments thereof will now be described by way of example, with reference to the accompanying drawings, in which:-

Figure 1 is a perspective view of an electrical plug receptacle connector according to a first embodiment of the invention, mounted on a printed circuit panel, in association with a mating electrical plug connector and a cover panel;
Figure 2 is a front elevation of the receptacle connector as seen in cross-section through the panel;
Figure 3 is a view taken on the lines III - III of Figure 1;
Figure 4 is an underplan view of the housing of the receptacle connector;
Figure 5 is a fragmentary underplan view of a printed circuit panel;
Figure 6 is a front elevational view, shown partly in section and showing the plug connector mated with the receptacle connector;
Figure 7 is a plan view of a metal blank illustrating steps in the manufacture of electrical contacts of the receptacle connector;
Figure 8 is an enlarged view taken on the lines VIII - VIII of Figure 7;
Figures 9 to 11 are sectional views illustrating successive stages in the use of tooling for the application of a section of the blank of Figure 7 to the housing of the receptacle connector to provide the housing with the contacts;
Figure 12 is a plan view shown partly in section illustrating the stage of Figure 9;
Figure 13 is a sectional view taken on the lines XIII - XIII of Figure 12;
Figure 14 is a sectional side view of an electrical receptacle connector according to a second embodiment of the invention;
Figure 15 is a perspective view of an electrical plug receptacle connector according to a third embodiment of the invention mounted on a printed circuit panel and in association with a mating electrical plug connector;
Figure 16 is a view taken on the lines . XVI - XVI of Figure 15;
Figure 17 is a top plan view of the receptacle connector of the third embodiment;
Figure 18 is a front elevational view of the receptacle connector of the third embodiment;
Figure 19 is a view taken on the lines XIX - XIX of Figure 16;
Figure 20 is a front elevational view shown partly in section and showing the receptacle connector of the third embodiment mated with the plug connector;
Figure 21 is a plan view of a metal progression strip, illustrating steps in the manufacture of electrical contacts of the receptacle connector of the third embodiment;
Figure 22 is an end view of a partially formed contact;
Figure 23 is a view similar to that of Figure 16 but illustrating a step in the assembly of the contacts to the receptacle connector of the third embodiment;
Figure 24 is a fragmpntary plan view illustrating a modification of the receptacle connector according to the third embodiment;
Figure 25 is a view taken on the lines XXV - XXV of Figure 24;
Figure 26 is a view similar to that of Figure 1 but showing an electrical plug receptacle connector according to a fourth embodiment of the invention;
Figures 27-and 28 are front elevational, and top plan views, respectively, of the receptacle connector according to the fourth embodiment;
Figure 29 is a view taken on the lines XXIX - XXIX of Figure 28.;
Figure 30 is a sectional view showing a receptacle connector according to the first embodiment and a receptacle connector according to the fourth embodiment, mounted on a common printed circuit board;
Figure 31 is a fragmentary underplan view of the printed circuit board;
Figure 32 is a plan view of a metal blank illustrating steps in the manufacture of electrical contacts of the receptacle connector according to the fourth embodiment;
Figures 33 and 34 are sectional views illustrating the manner in which the receptacle connector of the fourth embodiment is provided with the electrical contacts;
Figure 35 is a view similar to those of Figures 1 and 26 but showing an electrical plug receptacle connector according to a fifth embodiment of the invention;
Figure 36 is a view of the receptacle t connector taken on-the lines XXXVI - XXXVI of Figure 35;
Figure 37 is a top plan view of the receptacle connector of the fifth embodiment;
Figure 38 is a view taken on the lines XXXVIII - XXXVIII of Figure 36;
Figure 39 is a fragmentary underplan view of a printed circuit board;
Figure 40 is an enlarged perspective view with parts omitted, illustrating the manner in which electrical contacts of the receptacle connector of the fifth embodiment are inserted into holes in the printed circuit board;
Figure 41 is a view taken on the lines XXXXI - XXXXI of Figure 36;
Figure 42 is an enlarged plan view of a metal blank;
Figures 43 and 44 are sectional views illustrating the assembly of electrical contacts to the housing of the receptacle connector of the fifth embodiment; and
- Figure 45 is a view taken on the lines XXXXV - XXXXV of Figure 44.

Reference will now be made to Figures 1 to 13.
As shown in Figure 1 an electrical plug receptacle connector 2 is mounted on a printed circuit board 4, an electrical plug connector 68 being adapted to be mated with the receptacle connector 2. The receptacle connector 2 comprises an insulating housing 6 having a plug-receiving opening 12 extending through the housing 6 and between the ends 8 and 10. The opening 12 has opposed upper and lower internal side walls 14 and 16 (as seen in Figure 3) and opposed internal end walls 18 and 20, as best seen in Figure 2. The housing 6 has external side walls 22 and 24 and external end walls 26 and 28 which are adjacent to the internal side walls 14 and 16. The end walls 26 and 28 have extensions 30, which extend beyond the plug-receiving end 8, outwardly projecting flanges 32 being provided on the ends of the extensions 30. The housing 6 is mounted on the board 4 by means of locating pins 34 adjacent to the rearward end 10 of the housing 6, and which are received in circular openings 80 (Figure 5) in the board 4, and by latch arms 36 having enlarged ends 39 which are received in notches 78 (best seen in Figure 5) in an edge of the board 4. A cover panel 38 has an opening 40 shaped to receive the housing 6 when the panel 38 is moved downwardly from the position in which it is shown in Figure 1. The flanges 32 then extend laterally beyond the edges of the opening 40 and support the housing 6.
A plurality of spaced recesses 42 defining between them barriers 43, are provided in the plug-receiving end 8 of the housing 6, between the side walls 16 and 24, as best seen in Figure 3, each recess 42 merging with a slot 44 which extends partially along the side wall 16 from the plug-receiving end 8 of the housing 6. Each recess 42 also communicates with a narrow channel 46a or 46b in the external side wall 24. Each such channel has an inner closed end 48a or 48b the opposed sides of each channel having V-shaped recesses 50a or 50b, as best seen in Figure 4, the ends of the channels 46a being remote from the rearward end 10 of the housing 6 relative to ends 48b of the channels 46b and the recesses 50a being adajcent to the ends 48a. The ends of the channels 46b are proximate to the rearward end 10 of the housing 6, the recesses 50b being immediately adjacent to the ends of the channels 46b. The recesses 50a and 50b and the ends 48a and 48b are accordingly staggered with respect to the rearward end 10 of the housing. Barriers 51 of the housing material are defined between adjacent channels 46a and 46b.
A plurality of stamped and formed electrical contacts 52a and 52b are mounted in the housing 6, each such contact having an intermediate portion 54a or 54b which is located in one of the channels 46a or 46b, as the case may be, a bight 56 adjacent to the end 8 of the housing 6, and being located in the corresponding recess 42, and a contact spring portion 58 which extends obliquely into the opening 12 of the housing 6. A tail portion 60a or 60b of each contact extends normally of the portion 54a or 54b from its end remote from that from which the portion 58 extends, and downwardly, as seen in Figure 3, beyond the wall 24. The extremities 53 of these tail portions are dimensioned to be inserted into staggered holes 83 (Figure 5) in the board 4 to be soldered to conductors (not shown) on the underside of the board 4. Each contact 52a or 52b has outwardly extending barbs 62a or 62b which are force fitted into the recesses 50a and 50b, respectively, to retain the contacts 52a and 52b in the housing 6.
The plug connector 68 which is described in detail in United States Patent Specification No. 3,954,320, comprises an insulating housing having a recess therein which receives the end portion of an eight wire cable 70. The wires of the cable 70 are connected by means of insulation piercing connections (not shown) to blade-like terminals 74 (Figure 6) contained in the housing of the plug 68, edge portions of which terminals 74 are adjacent to the underside 72 of the plug housing. The edge portions of the terminals 74 thus engage the contact spring portions 58 when the plug 68 is inserted into the opening 12, as shown in Figure 6. The plug 68 is retained in the opening 12 by means of a latch arm 76 which extends from the upper (as seen in Figures 1 and 6) surface of the plug housing and which has shoulders 79 for engagement behind shoulders 66 (Figure 3) adjacent to the internal side wall 14, the opening 12 having an enlargement 64 to accommodate the latch arm 76.
In the course of their manufacture, the contacts 52a and 52b are stamped from a continuous length of metal sheet, for example of brass or beryllium copper in the form of strips 52a' and 52b', to provide a blank 84 as shown in Figure 7, each such strip being integral with spaced carrier strips 86 and 88. As shown on the right hand side of Figure 7, each strip 52a' and 52b' has outward projections 62a' and 62b', which are coplanar with the remainder of the blank 84, the projections 62a' being nearer to the carrier strip 86 than the projections 62b'. The strips 52b' are connected to the carrier strip 86 by neck portions 90 which are nearer to the carrier strip 86, than neck portions 92 which connect the strips 52a' to the carrier strip 86. As will be explained below, the individual strips 52a' and 52b' are sheared from the carrier strip 86 at the respective neck portions 90 and 92. Prior to shearing the neck portions 90 and 92, the projections 62a' and 62b' are deformed upwardly very slightly (as seen in Figure 8), to provide the barbs 62a and 62b, such deformation serving to facilitate the engagement of the barbs 62a and 62b with the walls of the recesses 50a and 50b.
The strips 52a' and 52b' can be assembled to the housing 6 and formed to provide the contacts 52a and 52b by means of insertion tooling, in the manner illustrated in Figures 9 to 13. The tooling comprises a fixed shearing member 190 in the form of a shearing block, a movable shearing member 192 in the form of a shearing blade, an insertion and forming ram assembly 94 which comprises two ram parts 96 and 98, and an additional shearing member 99 (Figure 10), in the form of a shearing blade. The shearing members 190 and 192 serve to sever the strips 52a' and 52b' from the carrier strip 86 and, as shown in Figure 12, shearing edges 100 and 102 of the member 192 are-offset from each other so that the strips 52a' are sheared from the carrier strip 86 as the neck portions 92 and the strips 52b' are severed at the neck portions 90, the member 190 having shearing edges (not shown) which are complementary with the edges 100 and 102.
The ram part 96 has spaced-apart support surfaces 104 for the strips 52a' and 52b' and recesses 106 on each side of each support surface 104 to permit the support surfaces 104 to insert the strips 52a' and 52b' into the channels 46a and 46b on the underside of the housing 6, the barriers 51 being received in the recesses 106. As shown in Figure 12, the support surfaces 104 for the strips 52b' extend beyond the support surfaces 104 for the strips 52a' because the channels 46b are longer than the channels 46a. The working surface 112 of the ram part 98 is coplanar with the support surfaces 104 when the ram parts 96 and 98 are in their position of Figure 9, however, spaced openings 110 extend vertically through the ram part 98 between adjacent surfaces 104 as shown in Figure 12. The openings 110 provide clearance for the barriers 43 between adjacent recesses 42 in the housing 6.
With the housing 6 supported in an upper tooling member (not shown), the required number of strips 52a' and 52b', which are to be formed into the contacts 52a and 52b for the housing 6, are assembled to the housing 6 by positioning a section (see the left hand side of Figure 7) of the blank 84 on the tooling 96, 98, 190 as shown in Figure 9, with the housing 6 supported above the tooling and with the strips 52a' and 52b' in alignment with respective channels 46a and 46b of the housing 6. During the insertion of the strips 52a' and 52b', the shearing member 192 is first depressed from the position of Figure 9 to sever the strips 52a' and 52b' from the carrier strip 86. These strips may be held on the ram assembly 94 by the shearing member 99 or by other hold down means (not shown). The shearing member 192 is then raised from the position of Figure 9 and the ram assembly 94 is raised as a unit from the position of Figure 9 to that of Figure 10.
As a result of such movement of the assembly 94 the tail portions 60a and 60b of the contacts 52a and 52b are formed by bending the corresponding end portions of the strips 52a' and 52b', as such end portions are pushed by the part 96 past rounded corners 101 at the closed ends of the channels 46a and 46b. The shearing member 99 then descends from the position of Figure 10, and in co-operation with the right hand (as seen in Figure 10) edge of the ram part 98 shears the carrier strip 88 from the strips 52a' and 52b'. The part 98 is then moved upwardly relative to the part 96, which remains stationary, partially to form the contact spring portions 58 of the contacts, as shown in Figure 11. The housing 6 is then removed from the tooling and the partially formed portions 58 are fully formed by bending them inwardly to their final positions (Figure 3), by inserting a gauging tool (not shown) into the opening 12 of the housing 6.
In the embodiment of Figure 14, i.e. the second embodiment, the extremities 53c of the tail portions of the contacts extend through shallow extensions 125 of the channels 46a and 46b, beyond the rearward end 10 of the housing. The housing of Figure 14 is intended to be mounted on a printed circuit board (not shown) with the rearward-end lO on the surface of the board. If desired, the extremities 53c may be offset from each other for insertion into holes in the printed circuit board arranged according to the pattern of the holes 83 of Figure 5.
A receptacle connector as described above can be readily mounted on the printed circuit board and its contacts soldered to conductors on the board without the use of intervening connecting devices or conductors. The tail portions of the contacts may otherwise be shaped, for example, so that their extremities can be mated with terminal receptacles (not shown) crimped to the ends of wires, or such extremities can be formed each with a slot (not shown) for receiving an insulated wire upon movement of the wire laterally of its axis and into the slot.
It is advantageous that the receptacle connector can be produced by injection moulding a one-piece housing, stamping the individual contacts, and inserting all of them into the housing in a single insertion operation.
The fact that the contacts of the receptacle connector are stamped and formed and have a substantial width, as illustrated in Figure 6, results in improved electrical characteristics in that the edge portions of each terminal of the plug connector bear against a flat surface of a contact member of the receptacle connector. It will be apparent from Figure 6 that slight misalignment of the terminals of the plug connector relative to the contacts of the receptacle connector will not affect the quality of the electrical connections, which always consist of two flat surfaces disposed against each other.
Reference will now be made to Figures 15 to 23.
The receptacle connector 202 according to the third embodiment is intended to be mated with a plug connector 68' (identical with the connector 68 described above excepting that it is for a four wire cable 70' instead of for an eight wire cable), to connect the wires 70' to conductors 207 (Figures 16 and 20) on the underside of a printed circuit board 210. As shown in Figures 15 and 16, the connector 202 comprises an insulating housing 212 of plastics material, for example a filled nylon, having a rearward end 214, a plug-receiving end 216, and a plug-receiving opening 218 extending through the ; housing 212 and between the ends 214 and 216. The opening 218 has upper and lower (as seen in Figure 16) internal side walls 220 and 222 and internal end walls 224 and 226 (Figure 18), the housing 212 having external side walls 228 and 330, external end walls 232 and 234 and support feet 236 which extend outwardly from the external end walls 232 and 234. The feet 236 are provided with locking lugs 237 on their_undersides, which lugs are dimensioned to be received in holes in the board 210 to retain the housing 212 on the board 210 prior to soldering the electrical contacts 260 in the housing 212 to the conductors 207 of the board 210. The external side wall 230 is supported above the board 210 by the feet 236 to facilitate the soldering operation. The feet 236 merge with a rearward apron 238 of the housing 212.
A contact-receiving opening 240 extends through the housing 212 parallel to, and adjacent to, the opening 218 and between the internal side wall 222 and the adjacent external side wall 230, as best seen in Figure 16. This opening 240 extends rearwardly through a recessed surface 242 below the portion 241 of the plug-receiving end 216 which is adjacent to the internal side wall 222. As best seen in Figure 19, the entrance to the opening 240 in the surface 242 is of restricted width and the sides of the opening 240 diverge rearwardly'as shown at 244. This divergent portion of the opening 240 merges with a wider portion 246 which extends to the rearward end 214 of the housing 212. An entrance 248 at such rearward end is flared, as shown in Figure 16, to facilitate assembly of the contacts 260 to the housing 212, as described below.
A ramp 250 extends down from the entrance 248 of the opening 240 to the upper surface 252 of the apron 238, spaced barriers 254 being provided on the ramp 250 and on the surface 252 to define a separate stall for each contact 260. Additionally, spaced V-shaped notches 256 extend inwardly from the rearward edge 258 of the apron 238 to receive the contacts 260 with an interference fit, also as described below.
The contacts 260 each comprise, as shown in Figure 16, an intermediate portion 262 which is contained in the opening 240 with a force fit afforded by dimples 264 on the portion 262. Adjacent to the end 216 of the housing 212, each contact 260 has a bight 266 received in one of a plurality of spaced notches 270, defining barriers 241 at the end 216 of the housing 212. Contact spring portions 268 of the contacts 260 which extend obliquely from the wall 222 into the opening 218, are deflected by the edge portions of the terminals 74' of the plug connector 68' when it is inserted into the opening 218 (Figure 20).
Tail portions 272 of the contacts 260 extend over the ramp 250 as shown in Figure 16, across the adjacent surface 252 of the apron 238 and through the notches 256, offset parts 274 of the portions 272 abutting the surface 252. The notches 256 are dimensioned to receive the portions 272 with an interference fit securely to anchor the ends of the portions 272 to the housing 212, the barriers 254 serving to restrain lateral movement of the contacts 260 towards or away from each other. Extremities 281 of the tail portions 272 extend downwardly beyond the wall 230 and are soldered at 280 to the conductors 207. Enlarged arcuate parts 278 of the tail portions 272, beneath the apron 238 provide the interference fit mentioned above and contribute to the stability of the contacts 260 with respect to the housing 212.
Shoulders 290 (Figures 16 and 23) in the opening 218 serve to engage the shoulder 79' of the latch arm 76' of the plug connector 68' to retain the latter in the housing 212.
The contacts 260 are manufactured from a progression strip 294 of spring metal (Figure 21). The strip 294 is prepared by punching suitable pilot holes 300 (for locating the strip) in the edge of the strip 294 and blanking the strip 294 to produce groups 309 of four contact blank strips 260'. The parts of each strip 260' are identified in Figure 21 by the same reference numerals, differentiated by "prime" symbols, as those used in the above description of the contacts 260. The strips 260' extend between, and are formed integrally with, spaced carrier strips 302 and 304. Sections 306 of the strips 304 between adjacent groups 309 of strips 260' at end portions 268' thereof, are first removed as shown in Figure 21. A forming operation can then be carried out to produce the offset parts 274 of the contact 260 and to produce the dimples 264, (Figure 22). A finished group of strips 260' then comprises a section 310 of the carrier strip 302 with groups of four partially formed contacts 260 extending there from and with the ends of the portions 268' of each such group connected by a remanent 308 of the carrier strip 304. Each of these groups 309 is assembled to a housing 212 after severing the section 310 of the carrier strip 296 from the strip 294 while leaving the remanents 308 of the carrier strip 304 and section 310 of the carrier strip 302, still connected to the strips 260'. The group 309 is then inserted into the rearward entrance 248, with the remanent 308 leading, to extend beyond the plug-receiving end 216 of the housing 212, as shown in Figure 23, diverging portions 243 of the'blanks 260' being received in the enlarged portion 246 of the opening 240. Thereafter, the remanent 308 and section 310 of the carrier strips are severed from the strips 260' and final forming of these blanks is carried out by bending the portions 268' so as to extend obliquely into the opening 218, and bending down the portions 272' of the strips 260' so as to extend over the ramp 250, across the surface 252 and through the notches 256. The enlarged parts 278' are now located adjacent to the lower surface of the apron 238 as shown in Figures 18 and 20 in which the enlarged portions are referenced 278 as being parts of the finished contacts. The parts 278 thereby assist in stabilizing the contacts 260 in the housing 212 and also restrain the portions 272 against upward movement through the notches 256 when the extremities 281 are inserted into the openings in the board 210 prior to the soldering operation.
According to the modification of Figures 24 and 25 extremities 322 and 324 of the tail portions of the contacts 26Qa and 260b are offset from each other so that the width of the housing at the rearward end thereof can be substantially reduced. It will be appreciated that in this case it is unnecessary for the intermediate portions of the contacts to be divergent, the contact-receiving opening 240a being of uniform width. Slots 316 and 318 extend inwardly from the rearward edge of the apron 238a, the slots 316 which receive the end portions of the contacts 260a being relatively deeper than the slots 318 which receive the end portions of the contacts 260b. All of the slots 316 and 318 have bases formed by ramps.250a which slope downwardly from the upper surface of the apron 233a, as shown in Figure 25, the contacts-260a and 260b extending across the ramps 250a and downwardly beyond the lower surface of the apron 23Sa, as seen in Figure 25. The contacts are also provided with outwardly extending barbs 326 which gouge into the side walls of the slots 316 and 318 when the contacts 260a and 260b are assembled to the housing and assist in retaining the contacts in assembled relationship. The modification of Figures 24 to 25 can thus be used under circumstances where it is desired to have a housing of reduced width and where the printed circuit board has staggered holes therein for reception of the extremities 324 and 322.
As in the case of the first and second embodiments, the receptacle connector of the third embodiment can be produced at a minimum of cost by automatic assembly tooling, as will be apparent from Figures 21 to 23 and the description relating thereto. The contacts 260 can be produced at very low cost by virtue of their simplified construction and the absence of a requirement for crimped connections in the housing, as described in United States Patent Specification No. 3,850,497. Moreover, the assembly of the contacts to the housing is carried out by inserting all of the strips 260' in a single insertion operation. The forming of the strips 260' after their insertion can also be carried out with simple assembly toolina (not shown) and at a very low production cost.
Although the receptacle connector 202 is intended to be mounted on a printed circuit board with the openings 218 and 240 extending parallel to the surface of the board, it will be apparent that the housing could be adapted to be mounted on the board with these openings extending normally of the surface of the board. For example, extensions could be provided on the rearward end 214 for supporting that end of the housing above the surface of the board, the tail portions of the contacts being formed so as to extend into openings in the board.

Reference will now be made to Figures

26 to 31. As shown in Figure 26, an electrical plug receptacle connector 403 according to the fourth embodiment of this invention is mounted on a printed circuit board 404 and serves to connect the wires of an eight wire cable 70 connected to a plug connector 68 identical with that described above with reference to the first embodiment, to conductors 90 (Figure 31) on the underside of the board 404. The connector 403 comprises a moulded insulating housing 406 of thermoplastics material, for example a filled nylon, having a plug-receiving end 408, a rearward end 410, and a plug-receiving opening 412 extending into the plug-receiving end 408. The opening 412 has lower and upper (as seen in Figures 27 and 29) internal side walls 414 and 416, and opposed internal end walls 418 and 420. The external surface of the housing 406 comprises lower and upper external side walls 422 and 424, respectively, and external end walls 426-and 428. The end walls 418 and 420 and the side wall 414 extend beyond the internal side wall 416 at the plug-receiving end 408 as shown at 430 in Figure 26, flanges 432 being provided on the end walls 426 and 428 and on the side wall 424. Integral mounting pins 434 which extend from the side wall 422 are dimensioned to be received for mechanical mounting purposes, in openings 488 in the board 404 (see Figures 27, 29, 31). Additionally, stand off bosses 436 are provided on the side wall 422 to support it slightly above the surface of the board 404 when it is mounted thereon.
The connector 403 is mounted adjacent to an edge of the board 404 so that a cover panel 438 engages this edge, when the connector 403 has been engaged in an opening 440 in the panel 438, with the flanges 432 engaging the rearward surface of the panel 438.
A plurality of juxtaposed recesses 442 (best seen in Figure 30) provided in the mating end 408 of the housing 406 between the side walls 416 and 424 merge with spaced grooves 444 in the side wall 414 and with spaced channels 446 in the side wall 424. Adjacent channels 446 are separated by barriers 448, the channels 446 and the barriers 448 extending downwardly, as seen in Figure 29, over the rearward end of the housing 406 to the lower external side wall 422.
As best seen in Figure 29, the upper portion of the opening 412 extends entirely through the housing 406 but a web 449 is provided at the rearward end of the housing 406, which extends between the lower portions of the internal end walls 418 and 420, the channels 446 and the barriers 448 being provided on the external surface of the web 449. Retaining shoulders 476 are provided in the opening 412.
Staggered recesses 450 communicating with the channels 446, are provided in the side wall 424, in the web 449 as shown at 463, and in the lower portion of the rearward end of the housing 406 as shown at 470, (Figure 29). The recesses 450 extend into the barriers 448 on each side of each channel 446.
The housing 406 is provided with spaced parallel electrical contacts 452 each having an elongate intermediate portion 454 extending across the side wall 424 (see Figure 30) and which is bent downwardly at 464, and which has a tail portion 466 extending downwardly across the rearward end 410 of the housing 406. A contact spring portion 458 of each contact 452 extends from a bight 456 disposed in one of the recesses 442 and projects obliquely into the opening 412.
The tail portion 466 of each contact 452 has an extremity 460 projecting beyond the side wall 422 for soldering to a conductor 490 on the board 404. Retaining barbs 463 on the contacts 452 are received in the recesses 450, these barbs being similar to the barbs 62a and 62b described above with reference to the first embodiment.
A central, downwardly (as seen in Figure 26), inclined recess 474, is provided in the internal side wall 414 and extends to the mating end 408 of the housing 406. Spaced shoulders 476 on each side of the recess 474, which shoulders face towards the rearward end 410 of the housing 406, are provided for co-operation with the shoulders 79 (Figure 30) on the latch arm 76 of the.plug connector 68.
The conductors 490 of the board 404 extend, as shown in Figure 31, to holes 492 in the board 404, arranged in two rows with the holes of one row staggered with respect to those of the other row. The extremities 460 of the contacts 452 are therefore correspondingly staggered with respect to each other, by making the channels 446 on the rearward end 410 of the housing 406 of different depths; alternate channels 446 being deeper than the remaining channels 446 so that the extremities 460 of the .contacts 452 in the deeper channels 446 form one row and the extremities 460 of the contacts 452 in the shallower channels 446 form another row, the extremities 460 of the one row being offset from, and staggered with respect to, the extremities 460 of the other row.
Figure 32 shows a sheet metal blank 494 comprising spaced strips 452' for assembly to housing 406, the blank 494 being shown as being unformed on the right hand side of Figure 32, a short section of the blank as formed, being shown on the left hand side of that Figure. The blank 494 comprises spaced continuous carrier strips 496 and 498 with the strips 452' extending there between. Each strip 452' has a reduced width neck 500 adjacent to the carrier strip 496, which neck 500 is severed from the carrier strip at the time of the assembly of the strips 452' to the housing 406. The barbs 463 on the conductors are relatively staggered as shown in Figure 32.
The formed strips 452' can be assembled to the housing 406 in a similar manner to that described above with reference to the first embodiment. A formed section of the strip 494 having the required number of strips 452' for the housing 406 is severed from the strip 494 and each strip 452' of the severed section is placed in alignment with one of the channels . 446 in the external side wall 424 (see Figure 33). The formed section is then moved downwardly (Figure 34) so that the strips 452' enter the channels 446. Thereafter, the carrier strip 498 is severed from the section of the strip 494 and the end portions of the strips 452', which extend beyond the plug-receiving end 408 of the housing 406 are bent downwardly and into the plug-receiving opening 412. The bending of these end portions may be carried out in two steps, namely a first step in which such end portions are bent downwardly so that they extend normally of the intermediate portions of the strips 452' and across the plug-receiving opening 412, and a second step in which said end portions are bent so as to extend obliquely into the opening 412 to form the contact spring portions 458.
After the portions 458 have been so formed, the carrier strip 496 is severed from the strips 452' and the ends thereof which project beyond the rearward end 410 of the housing 406 are bent downwardly, to enter the channels 446 in the rearward end 410. Tooling for carrying out these insertion, bending and severing steps may be of the general type used with the first embodiment.
The receptacle connector 403 is mounted on the board 404 merely by aligning the extremities 460 of_the contacts 4'52 with the holes 492 and aligning the pins 434 with the holes 488 and inserting the pins 434 and the extremities 460 into the respective holes until the bosses 436 abut the surface of the board 404. The extremities 460 can then be soldered to the conductors 490.
Figure 30 shows a connector 403 on the right side of the board 404 and a connector 2 in accordance with the first embodiment, on the left hand side of the board 404. It will be readily apparent that the latch member 76 of the plug connector 68 on the left hand side of the board 404 is readily accessible so that the connector 68 can be removed from the receptacle connector 2 with ease. However, the latch member 76 of the plug connector 68 which is mated with the receptacle connector-403 is on the underside of the body of that connector 68 so that while such connector can, it necessary, be withdrawn from the connector 403, it cannot readily be so withdrawn, for example by a small child.
As shown in Figures 35 to 39, an electrical plug receptacle connector 502, in accordance with the fifth embodiment of the invention, serves to connect the wires of a six wire cable 70'' to conductors 506 (Figure 39) on the underside of a printed circuit board 510, by way of an electrical plug connector 68" identical with the connectors 68 and 68' mentioned above, excepting that it has six contacts 74'' , instead of four or eight such contacts as in the case of the plug connectors described above. The conductors 506 extend to holes 507 (Figure 39) in the board 510, which receive extremities 556 and 556' of electrical contacts 544 of the connector 502 so that the contacts can be soldered to the conductors 506.
The connector 502 comprises a one-piece moulded insulating housing 518 made for example of a filled nylon, and having a plug-receiving end 520, a rearward end 522, and a plug-receiving opening 524 extending into the plug-receiving end 520. The opening 524 has upper and lower (as seen in Figure 36) internal side walls 526 and 528 and opposed end walls 530 (Figure 38). The housing 518 has upper and lower external side walls 532 and 534 which are proximate to the internal side walls 526 and 528 respectively, and oppositely directed external end walls 536. Mounting feet 538 extending from the lower external side wall 534 are dimensioned to enter spaced holes 540 in the circuit board 510, stand off bosses 542 being provided on the side wall 534 to elevate it above the board 510 when the housing 518 is mounted thereon.
The contacts 544 are contained in and on, the housing 518. As best seen in Figure 40, each contact 544 has a contact spring portion 546 having a free end 566 and extending from a bight 548, an intermediate portion 550 which extends, as seen in Figure 40, back from the bight 548, a further bight 552, and downwardly extending tail portions 554 and 554'. The lower extremities 556 and 556' of the portions 554 and 554' are intended for insertion into the holes 507 of the board 510 and are offset from each other so that they can be received in the holes 507.
The portions 550 are disposed in parallel juxtaposed channels 558 in the upper external side walls 532. The channels 558 extend from the rearward end 522 of the housing 518'to spaced apertures 560 which are adjacent to, but are spaced from, the plug-receiving end 520. The bights 548 of the contacts 544 extend through the apertures 560 and about conforming surfaces of the housing 518, as shown in Figure 36. The internal side wall 526 has spaced recesses 562 dimensioned to receive the contact spring portions 546 of the contacts 544 when the plug connector 68'' is mated with the connector 502. Upon insertion of the plug connector 68'' into the opening 524, the portions 546 are flexed upwardly as indicated by the arrow "A" in Figure 36 and resiliently engage the exposed contacts 74" of the plug connector 68''. The recesses 562 are enlarged at 564 adjacent to the apertures 560, to permit such flexure.
A plurality of parallel spaced barriers 568 extend downwardly into the opening 524 from the upper side wall 526 adjacent to the rearward end 522, to define stalls which receive the free ends 566 of the contact spring portions 546. Additionally, a backwall 570 extends across the opening 524 as shown in Figure 36, partially enclosing the opening 524 at its rearward end. The barriers 568 render it impossible for a small child to insert a finger into the plug-receiving opening 524 to a point beyond the free ends 556 of the contact spring portions 546 in such a way that when the finger is withdrawn it is impaled on the ends 566. The back wall 570 reinforces the barriers 568 and also serves to prevent shorting circuiting between the contacts 544, as described below.
.As will appear from Figures 37, 41 and 45, channels 572 and 572' are provided in the outwardly sloping rearward end of the housing 518 adjacent to the external side wall 532', additional contact-receiving channels 576 and 576' (Figure 41) being provided in the rearward end of the housing 518 adjacent to the lower external side wall 534. The channels 576' are deeper than the channels 576.
The contacts 544 extend from the upper external side wall 532 into the channels 572 and 572' and downwardly beyond the lower external side wall 534. The downwardly extending portions of the contacts 544 are spread apart in two senses, the centre-to-centre spacing between the contacts 544 (x in Figure 40) is increased and additionally the extremities 556 are offset from the extremities 556' to enable all these extremities to be received in the holes 507 which are arranged according to triangular patterns. The deeper channels 567' receive the portions 554' which extend across the rearward surface of the wall 570 while the portions 554 extend outwardly from the wall 570 in the shallower channels 576. Retaining barbs 578 (Figure 42) on the contacts 544 adjacent to their extremities 556 and 556' are received in recesses in the side walls of the channels 576 and 576' to retain the contacts 544 in the channels 576 and 576'. The lances 578-are not shown in Figure 40.
The centre-to-centre spacing of the contact spring portion 546 in the connector 502 are required, according to current specifications, to be 0.04" (the spacing in Figure 40). This spacing of the contacts and thus.of the holes 507 is close enough to give rise to dielectric problems in the absence of measures being taken to avoid this. The provision of the channels 576 and 576' on centres x, which is greater than the spacing y, overcomes this problem and improved dielectric characterisitcs are achieved when the connector 502 is put to use. As mentioned above, the back wall 570 prevents short circuiting between the contacts 544, in that the ends 566 are separated by an insulating wall from the portions 554 and 554' of the contacts 544. In the absence of the wall 570, the insertion of a misdimensioned plug connector might cause the end 566 of a contact 544 to be pushed against the portion 544 or 544' of an adjacent contact 544.
The plug-receiving end 520 of the housing 518 has a continuous frame 580 surrounding the plug-receiving opening 524, a continuous flange 582 extending from the frame 580. When the connector 502 is mounted as shown in Figure 35, on the board 510, a cover panel.594 can be located against the forward edge of the board 510, with the frame 580 received in a rectangular opening 596 in the panel 594, the flange 582 hiding the edges of opening 596.
The opening 524 has an upwardly inclined ramp 590 at its mating end, which extends to spaced shoulders 592 which co-operate with the shoulders of the latch arm 76'' of the plug connector 68" to retain it in the opening 524.
In the manufacture of the receptacle connector 502, the contacts 544 are produced from a continuous blank strip 601, as shown in Figure 42, by stamping the strip-601 and forming it as shown. The barbs 578 on individual strips 603 from which the contacts 544 and 544' are to be formed, are offset from each other in view of the close spacing of the contacts in the housing.518, and additional barbs 579 are provided to secure the portions 550 of the contacts in the channels 558.' The strip 601 comprises a carrier strip 598 at its edge nearest to the lances 578 and a narrower carrier strip 600 at its opposite edge.
The contacts are assembled to the housing 518, as shown in Figures 43 and 44, after first removing the carrier strip 600 from a section of the strip 601, forming a right angle bend 548' therein, and positioning the section of the strip 601 above the housing 518, as shown in Figure 43, with the downwardly (as seen in Figure 43) extending portions 546' of the strip 601 each in alignment with one of the apertures 560.
The section of the strip 601 is then moved downwardly to the position of Figure 44 so that the portions 550 of the contacts to be formed lie in the channels 558. At this stage, the free ends of the portions 546' are adjacent to the shoulders 592, the opening 524 being dimensioned so that there is sufficient clearance between the side wall 528 and the free ends of the portions 546'. The contact spring portions 546 of the contacts 544 and 544' can then be formed by bending the portions 546' inwardly by means of a gauge tool (not shown). The portions of the strip 603 which extend to the left (as seen in Figure 44) are moved downwardly and are moved laterally by varying amounts to position them in the respective channels 572, 572', 576 and 576' in the rearward-end of the housing 518, the carrier strip 598 being removed before this final step is carried out.
Another advantage of this embodiment is that the apertures 560 are spaced from the plug-receiving end 520 of the housing 518 by a distance which is greater than the corresponding distance in the case of the other embodiments, whereby the contact spring portions of the contacts are shorter, than in the other embodiments. Since these shorter contact spring portions are stiffer, the contacts may be made of a thinner gauge material without sacrifice of contact force.
A further advantage of this embodiment, is that notwithstanding the fact that the extremities 556 of the contacts are offset from the extremities 556' thereof, the contacts themselves can all be of the same length as shown in Figure 42. In the present embodiment, the slope of the portions 554 of the contacts 544 is reliatvely gentle, the extremities 556 of the contacts not being located in the same plains as the lower extremities 556'. The extremities 556 are, in practice, slightly above the extremities 556'. Such difference in level is, however, very slight and all the extremities 556 and 556' extend below the underside of the board 510 so that they can be soldered to the conductors 506 thereon.
According to a modification of the present embodiment, the blank for producing the contacts may be of the same general shape as the blank shown in Figure 21, the housing being suitably modified to accommodate the divergent portions of the contacts.

Claims

1. An electrical plug receptacle connector (2, 202, 403 or 502) comprising an insulating housing (6, 212, 406 or 518) having a plug-receiving end (8, 216, 408 or 520) and a rearward end (10, 214, 410 or 522), a plug-receiving opening (12, 218, 412 or 524) extending into the plug-receiving end, such opening having opposed internal side walls (14 and 16, or 220 and 222, or 414 and 416, or 526 and 528) and opposed internal end walls (18 and 20, or 224 and 226, or 413 and 420, or 530), the housing having opposed external side walls (22 and 24, or 228 and 230, or 422 and 424, or 532 and 534) and opposed external end walls (26 and 28, or 232 and 234, or 426 and 428, or 536), a plurality of electrical contacts (52, 260, 452 or 544) arranged in juxtaposed spaced relationship, each comprising a contact spring portion (58, 268, 458 or 546) extending from one (16, 222, 414 or 526) of the internal side walls at a position adjacent to the plug-receiving end, obliquely into the opening (12, 218, 412 or 524) and towards the opposite internal side wall (14, 220, 416 or 528), and each contact having a portion (54, 262, 454 or 550) extending from the plug-receiving end through the housing between the one internal side wall (16, 222, 414 or 526) and the adjacent external side wall (24, 230, 424 or 532) and towards the rearward end of the housing, the plug-receiving opening (12, 218, 412 or 524) being dimensioned to receive an electrical plug connector (68, 68' or 68") having spaced contact members (74, 74' or 74") therein for engaging the contact spring portions (58, 268, 458 or 546) of the contacts of the receptacle connector (2, 202, 403 or 502); characterised in that each of the contacts (52, 260, 452 or 544) has been formed from a single elongate, flat strip of metal (52a', 260', 452' or 603), an intermediate portion (54, 262, 454 or 550) of such strip being disposed in a contact-receiving channel (46, 240, 442 or 576) extending from the plug-receiving end (8, 216, 408 or 520) of the housing towards the rearward end (10, 214, 410 or 522) thereof, a portion (58, 268', 458 or 546) of the strip extending from one end of the intermediate portion, having been bent back over a portion of the plug-receiving end (8, 216, 408 or 526) between the one internal side wall and the adjacent external side wall, to provide the contact spring portion (58, 268, 458 or 546), a tail portion (60a, 272, 466 or 554) of the strip extending from the other end of the intermediate portion and beyond the housing, projections (62a, 278, 463 or 578) extending laterally from the strips (52a', 260', 452', or 603) providing mechanical interference connections between the contacts and the housing to maintain the contacts in assembled relationship to the housing.

2. A receptacle connector according to Claim 1, characterised in that each contact (52, 452 or 544) is received in one of a plurality of juxtaposed channels (46a, 446 or 572) in the adjacent external side wall (24, 424, or 532), the lateral projections comprising barbs (62a, 463, or 579) on the intermediate portion (54, 454 or 550) of each of the contacts (52, 452 or 544), the barbs extending into the walls of the channels (46a, 446 or 572), and the barbs on each contact being offset with respect to the barbs (46b, 446 or 572) on the adjacent contacts, in the direction from the plug-receiving end (8, 408 or 520') to the rearward end (10, 410 or 522), of the housing.

3. A receptacle connector according to Claim 1, characterised in that the connector (2 or 202) is adapted to be mounted on a printed circuit board (4 or 210), the housing (6 or 212) having mounting and supporting means (36, 39 or 234) for supporting the housing on the board (4 . or 210), with the adjacent external side wall (24 or 230) of the housing adjacent to the surface of-said board (4 or 210), the tail portion (60a or 272) of each of contact (52 or 260) extending laterally of the housing (6 or 212) and away from the adjacent external side wall (24 or 230).

4. A receptacle connector according to Claim 1 or 3, characterised in that the housing (212) has a single contact-receiving channel (240) extending there through from the rearward end (214) to the plug-receiving end (216), the channel (240) being defined between the one internal side wall (222) and the adjacent external side wall (230), and being of a width sufficient to receive the intermediate portions (262) of the contacts (260) in juxtaposed coplanar relationship, the contacts (260) being stamped and formed from sheet metal, contact positioning and retaining means (256) being provided at the rearward end of the adjacent external side wall (230), and being effective to secure said tail portions (272) of the contacts (260) against lateral movement towards each other, whereby, the intermediate portions (262), the contact spring portions (268), and the tail portions (272) of the contacts (260) are maintained in spaced relationship at predetermined positions in the contact receiving channel (240) and the plug-receiving opening (218).

5. A receptacle connector according to Claim 4, characterised in that the housing (212) has an apron (238) extending from its rearward end (214), between the contact-receiving channel (240) and the adjacent external side wall (230), the contact positioning and retaining means being provided on the apron (238) and comprising contact-receiving notches (256) in edge portions of the apron (238), which are remote from the rearward end (214) of the housing (212), the tail portions (60a) of the contacts (260) extending through these notches (256) and beyond the adjacent external side wall (230), the housing (212) being adapted to be mounted on a printed circuit board (210) with the contact-receiving channel (240) parallel to the board (210), the contact positioning and retaining means further comprising enlarged portions (278) of the contacts (260), adjacent to the notches (256), and serving to prevent retraction of the tail portions (260a) of the contacts through the notches (256).

6. A receptacle connector according to Claim 4 or 5, characterised in that the contact-receiving channel (240) has an entrance (242) of restricted width at the plug-receiving end (216) of the housing (212), and a rearwardly diverging portion (244) of increasing width extending from the entrance (242) towards the rearward end (214) of the housing (212), the contacts (260) being splayed away from one another in the diverging portion (244), the tail portions (272) of said contacts (260) being spaced apart by greater distances than the contact spring portions (268) thereof.

7. A receptacle connector according to Claim 1 or 2, characterised in that the rearward end (410) of the housing (406) has a plurality of juxtaposed contact-receiving channels (446) therein, the channels (446) in such rearward end (410) being in alignment with the channels (446) in the adjcaent external side wall (424), each contact (452) comprising a single elongate strip of stamped and formed sheet metal, the intermediate portion (454) of each contact (452) being disposed in one of the channel (446) in the adjacent external side wall (424), the contact.(452) having been bent at the rearward end (410) of the housing (412) and extending across such rearward end (410)' in one of the channels (446) in the reardward end (410).

8. A receptacle connector according to Claim 1 or 2, characterised by a plurality of spaced barriers (568) extending from one of the internal side walls (526) at a location adjacent to the rearward end (522) of the housing (518) towards the opposite internal side wall (528), the contact spring portions (546) of the contacts (544) having free end portions (566), each positioned between an adjacent pair of the barriers (568).

9. A receptacle connector according to Claim 1, 2 or 8, characterised by a back wall (570) at the rearward end (522) of the housing (518) extending from one of the internal side wall (526) towards the opposite internal side wall (528), the contacts (544) extending from the adjacent external side wall (532) across the back wall (570) and beyond the other external side wall (534).

10. A method of manufacturing an electrical plug receptacle connector (2, 202, 403 or 502) comprising an insulating housing (6, 212, 406 or 518) having a plug-receiving end (8, 216, 408 or 520) and a rearward end (10,.214, 410 or 522), a plug-receiving opening (12, 218, 412 or 524) extending into said plug-receiving end, such opening having opposed'internal side walls (14 and 16, or 220 and 222, or 414 and 416, or 526 and 528) and opposed internal end walls (26 and 28, or 232 and 234, or 426 and 428, or 536), the housing having opposed external side walls (22 and 24, or 228 and 230, or 422 and 424, or 532 and 534) and opposed external end walls (26 and 28, or 232 and 234, or 426 and 428, or 536), a plurality of electrical contacts (52, 260, 452 or 544) arranged in juxtaposed spaced relationship, each comprising a contact spring portion (58, 268, 458 or 546) extending from one (16, 222, 414 or 526) of the internal side walls at a position adjacent to the plug-receiving end, obliquely into the opening (12, 218, 412 or 524) and towards the opposite internal side wall (14, 220, 416 or 528), and each contact having a portion (54, 262, 454 or 550) extending from the plug-receiving end through the housing between the one internal side wall (16, 222, 414 or 526) and the adjacent external side wall (24, 230, 424 or 532) and towards the rearward end of the housing, the plug-receiving opening (12, 218, 412 or 524) being dimensioned to receive an electrical plug connector (68, 68' or 68") having spaced contact members (74, 74' or 74") therein for engaging the contact spring portions (58, 268, 458 or 546) of the contacts of the receptacle connector (2, 202, 403 or 502); the method being characterised by the steps of arranging a series of elongate metal strips (52a', 260', 452' or 603) connected together in juxtaposed relationship, so that an intermediate portion (54, 262, 454 or 550) of each strip is disposed in a contact-receiving channel (46, 240, 442 or 576) extending from the plug-receiving end (8, 216, 408 or 520) of the housing towards the rearward end (4, 214, 410 or 522) thereof, with one end portion of each strip projecting beyond the plug-receiving end (8, 216, 408 or 520) of the housing and the opposite end portion of each strip projecting beyond the rearward end (10, 214, 410 or 522) of the housing, employing tooling to bend, in co-operation with a first edge portion of the plug-receiving end (8, 216, 408 or 520) between the one internal side wall and the adjacent external side wall, the one end portion of each strip back from the plug-receiving end (8, 216, 408 or 520) of the housing to cause such one end portion to extend obliquely into the plug-receiving opening (12,218, 412 or 524), and to bend the opposite end portion of the strip so that at least an extremity (53 or 53c, or 281 or 460 or 556) of such portion projects outwardly of the housing (6, 212, 406 or 518), the method also including the steps of severing the connections between the metal strips and producing an interference mechanical connection between a lateral projection (62a, 278, 463 or 578) on each strip, and the housing, to retain the strips (52a', 260', 452' or 603) in assembled relationship to the housing.