ELECTRICAL CONNECTOR SOCKET

Abstract: An electrical socket connector (10) comprises a housing (11) having a plug receiving cavity (16) in which a number of terminals (31) extend rearwardly from a cavity mouth (17) across a plug insertion plane. Preselected terminals (31) are prestressed with free ends (33) in engagement with a shunt (28) at a rear of the cavity (16) to one side of the insertion plane prior to plug insertion. Insertion of a plug (35) deflects the terminals (31) away from the shunt (28). The terminals (31) are upset to provide contact surfaces (51, 51') engaged by the plug (35) when fully inserted which surfaces (51, 51') extend along the insertion plane so that limited movement of the plug (35) in either direction along the insertion plane will not cause further deflection of the terminals (31).

Description: ELECTRICAL CONNECTOR SOCKET The invention relates to electrical connector assemblies comprising plugs and sockets and , in particular, to those assemblies which are adapted for use in data transmission applications and which have shunted terminals. One example of a prior assembly is disclosed in U. S. Patent 4, 274,691 in which an electrical socket connector comprises an insulating housing having front and rear ends , spaced apart wall portions extending between the ends defining between them a plug receiving cavity open at a plug receiving mouth at the front end , a row of resilient elongate cantilever terminals mounted on the housing to extend into the cavity obliquely across a plug insertion plane with root ends on one side of the insertion plane and free ends on the other side of the plug insertion plane, a shunt mounted on the housing and having contacts extending into the cavity aligned with surfaces of the free ends of preselected terminals which are prestressed into engagement with the contacts , such that insertion of a plug into the cavity brings axial ly extending conductive members on the plug along the insertion plane into engagement with respective terminals at locations between their ends causing deflection of the free ends of the terminals to disengage them from the shunt contacts. However, a problem that is met with such assemblies is that any inadvertent movement of the plug in the socket along the insertion plane arising , for example, as a result of play , will result in variations in the separation of the terminals from the wall with consequential movement of the free ends of the terminals towards or away from the shunt contacts . Such movement or play of the plug arises not only as a result of manufacturing tolerances , themselves a problem with - small , moulded parts but is particularly significant when the plug is of the type which is latched in the socket by engagement between a rearwardly facing abutment in the socket and a latching shoulder carried on a resilient latching arm extending rearwardly of the plug body from a root end of the latching arm integral with the plug adjacent a mating face. In plugs of this type, the length of the latching arm in the plug insertion direction will vary from a maximum during insertion movement when the abutment and latching shoulder are adjacent and the arm is most adjacent the body , to a minimum when the abutment and shoulder are juxtaposed in the latching condition , the arm having resiled away from the body. Thus , significant return movement of the plug will be produced . Increasing the clearance between the shunt contacts and the free ends of the terminals in the fully inserted condition of the plug in an attempt to avoid any consequent inadvertent engagement between the shunt contacts and the free ends of the terminals on return axial movement of the plug may result in an undesirably large housing . Furthermore, it is desirable that the shunt contacts are located as close as possible to the terminals in the fully inserted condition of the plug so that the terminals can be prestressed to a maximum thereagainst to optimize the electrical connection without a requirement for terminals having excessively stiff spring characteristics. According to the invention , in a plug and socket assembly as described above, the terminals are upset between their ends, the upset providing portions of the surfaces engaged by the plug conductive members in the fully inserted condition of the plug extending parallel to the insertion plane so that limited travel of the plug along the insertion axis is accommodated without further deflection of the terminals. As a result, the return movement of the plug will not affect the relative separation of the terminals and shunt contacts . In consequence, there will be no risk of their inadvertent connection and the shunt contacts can be located more closely to the free ends of the terminals in the fully inserted condition of the plug than would otherwise be practicable. This will enable the terminals to be prestressed against the shunt contacts to a maximum degree in the unmated condition of the assembly to increase efficiency of connection and the current carrying capacity. In addition , it enables the terminals to be made of a material having a soft spring characteristic and greater current carrying capacity such as beryllium copper rather than a stiff material such as phosphor bronze. Furthermore, there is no camming out force exerted' on the plug by the terminals in the fully inserted condition of the plug . More specifically , the terminals extend rearwardly from root ends adjacent the mouth , the shunt being located at the rear end of the housing and the upset defining a dog leg configuration . Preferably, the upset comprises a convex contact surface having an axis of generation perpendicular to the longitudinal axis of the terminal which surface has been plated subsequent to formation and the remaining portion of the terminal between the arcuate contact surface and the free end has been bent away from the arcuate contact surface after plating so that such portion does not cross the insertion plane in the fully inserted condition of the plug. The convex surface forms a discontinuity of work hardened material which resists deformation and provides a fold line facilitating the bending of the remainder of the terminal . In addition , as substantially no deformation of the arcuate surface is produced by the bending , surface strain and consequential cracking of the plating applied to the arcuate surface is obviated. In one embodiment, the convex contact surface is constituted by a wall of a depression struck into the contact surface. In an alternative embodiment, the convex contact surface is constituted by a protuberance struck out of the contact. Examples of a plug and socket connector assembly according to the invention will now be described with reference to the accompanying drawings in which : Figure 1 is an isometric view of the assembly according to the invention with a socket connector according to the invention partly in cross-section; Figure 2 is a cross-sectional view taken along the axis of plug insertion; Figure 3 is a similar view of Figure 2 but with a plug in a fully inserted condition in the socket; Figure 4 is a rear elevational view of the socket connector; Figure 5 is a fragmentary view of a strip of terminals in a first stage of forming the upset; Figure 6 is a fragmentary view of a fully upset terminal engaging a plug conductor; Figure 7 is a fragmentary view of a strip of terminals in a first stage of forming an alternative upset; and , Figure 8 is a fragmentary view of a fully upset portion of a terminal engaging a plug conductor. The socket 10 comprises a housing body 1 1 moulded from suitable plastics material and having opposite side, top and base walls 13 , 14 and 15 , respectively , defining a plug receiving cavity 16 and extending between a plug receiving mouth 17 at a front and an end wall 18 at a rear. The side walls 13 , are suitably stepped to form ledges 12 guiding the plug into the cavity along an insertion plane spaced the base wall 15. The base wall 15 is formed with a transverse row of terminal receiving apertures 19 at a location spaced from the mouth 17 and , rearwardly of the apertures , with a ramp 20 provided with a cam surface 21 extending to chamfered lips 22 defining edges of the apertures 19. A row of spaced barriers 23 upstand from the base 15 between the apertures in alignment with a row of barriers 24 located in a recessed part 25 of the end wall 18. A series of apertures 26 are also formed in the end wall 18 in communication with the recessed part in alignment with the interstices of the barriers 24. A shunting strip 28 similar to that described in our Japanese Patent Application No. 85/66378 filed March 29 , 1985 to which reference is hereby directed is fixed to the exterior of the end wall and comprises a web portion 29 from which outstand a series of preselected contact fingers 30 which protrude through aligned apertures 26 into the cavity 16. Stamped and formed metal terminals 31 extend in a row through respective apertures 1 9 rearwardly into the cavity 16 in cantilever spring fashion with root ends 32 located adjacent the lips 22 between adjacent barriers. The terminals diverge rearwardly away from the ramp 20 of the base wall 15 with free ends 33 located between adjacent barriers 24. The terminals have an upset 34 formed by a bend between their ends providing a dog leg configuration and contact surfaces which extend parallel to the insertion plane when a plug 35 is fully inserted into the socket. The shunt contact fingers 30 are aligned with surfaces of free ends 33 of the preselected terminals which surfaces face away from the bottom wall and those terminals are prestressed into engagement with the contact fingers 30 in the unmated condition of the socket. A shield 40 is fixed around the mouth of the housing substantially similar to that described in U . S. Patent No. - 4 , 457 , 575. The plug member 35 comprises a body 36 moulded from insulating material and having conductors with blade portions 37 extending into recesses 38 defined between fins 39 at a lower part of a mating face and trifurcated wire-connecting portions 41 terminating respective wires 42 received in a cavity therein . The plug body is surrounded by a stamped and formed metal shield member 43 similar to that described in U . S. Patent No. 4, 457, 575 , which effects connection with the stamped and formed metal shield extending around the socket mouth when the plug is mated therewith . The plug is provided with a latching arm 44 of known type which has a root end 45 integral with the plug body adjacent the mating face and diverges from the body as it extends rearwardly towards a rearwardly facing shoulder 46. In use, the latching arm is flexed toward the body during insertion of the plug into the socket housing until the shoulder 46 snaps into latching alignment with a rearwardly facing stop surface 47 formed in a recess in the socket body in known manner. On mating the plug with the housing , the flat, axially extending edges of the blade portions 37 of the conductive members move along the insertion plane progressively engaging the terminals 31 urging them towards the base wall 15 forcing the preselected terminals out of engagement with the shunt contacts. In the fully mated condition of the plug , the axially extending blade edge surfaces engage the upset 34 with the result that return movement of the plug will not alter the separation of the free ends 33 of the terminals and the base wall . Preferably , the terminals are bent such that the free ends of the terminals extend parallel to the base wall . Any back play of the plug is therefore accommodated without risk of the free ends of the preselected terminals engaging the shunt contacts. In preferred examples of terminals shown in Figures 5 though 8 , strips 50 and 50' of terminals (Figure 5 and Figure 7 respectively) have been upset by forming contact surfaces 51 and 51' of arcuate section having axes of generation perpendicular to the longitudinal axis of the terminal . The surfaces have subsequently been plated and the remaining portions of the terminal between the arcuate contact surfaces and the free ends have subsequently been bent by assembly tooling and carrier strips 54 and 54 1 removed so that the remaining terminal portion is not divergent with respect to the base wall and does not cross the insertion plane in the fully inserted condition of the plug . In the embodiment of Figures 5 and 6 , the arcuate contact surface 51 is constituted by a wall of a depression 53 struck into the contact surface and the remainder of the terminal is bent as shown in broken lines to form the dog leg . In the alternative of Figures 7 and 8 , the arcuate contact surface 51 ' is constituted by a protuberance 54 struck out of the contact and the remainder of the terminal is subsequently bent to form the dog leg . The cross-sectional area of the contact surface is of increased size, improving the effectiveness of the connection , and of decreased thickness as a result of spreading by the striking action. An advantage of forming the upset contact surfaces , plating and subsequently being only the free end of the terminals is that no deformation of the contact surface is produced which avoids surface strain which could otherwise fracture the plating .

Claims: CLAIMS: 1. An electrical socket connector (10) comprises an insulating housing (11) having front and rear ends, spaced apart wall portions (13,14,15) extending between the ends defining between them a plug receiving cavity (16) open at a plug receiving mouth (17) at the front end, a row of resilient elongate cantilever terminals (31) mounted on the housing (11) to extend into the cavity (16) obliquely across a plug insertion plane with root ends (32) on one side of the insertion plane and free ends (33) on the other side of the plug insertion plane, a «_* shunt (28) mounted on the housing (11) and having contacts (30) extending into the cavity (16) aligned with surfaces of the free ends (33) of terminals, which are prestressed into engagement with the contacts (30), such that insertion of a plug (35) into the cavity (16) brings axially extending conductive members (37) on the plug (35) along the insertion plane into engagement with respective terminals (31) at locations between their ends causing deflection of the free ends (33) of the terminals (31) to disengage them from the shunt contacts (30), characterized in that, the terminals (31) are formed with an upset (34) between their ends (32,33) providing portions of the surfaces (51 or 51') engaged by the plug conductive members (37) in the fully inserted condition of the plug (35) extending parallel to the insertion plane so that limited travel of the plug (35) in either direction along the insertion plane is accommodated without further deflection of the terminals (31). 2. An electrical socket connector according to claim 1 , characterized in that, the terminals (31) extend rearwardly from root ends (32) adjacent the mouth (17), the shunt (28) being located at the rear end of the housing (11) and the upset (34) defining a dog leg configuration. 3. An electrical connector socket (10) according to claim 1 , characterized in that the upset comprises a convex contact surface (51 or 51') having an axis perpendicular to the longitudinal axis of the terminal (31 ) which surface (51 or 51 ' ) has been plated subsequent to formation , the remaining portion of the terminal (1 1 ) between the arcuate contact surface (51 or 51 ' ) and the free end ( 33) having been bent away from the arcuate contact surface after plating so that the remaining terminal portion does not cross the insertion plane in the fully inserted condition of the plug (35) . 4. An electrical connector socket ( 10) according to claim 2 , characterized in that, the convex contact surface (51 ) is constituted by a wail of depression (53) struck into the contact surface. 5. An electrical connector socket ( 10) according to claim 2 , characterized in that, the convex contact surface (51 ') is constituted by a protuberance (54) struck out of the contact surface. 6. An electrical connector socket ( 10) according to any one of the preceding claims characterized by the combination with a plug (35 ) comprising an insulating body (36) carrying a row of conductive members (37) at a front, mating face aligned with respective terminals (31 ) and being provided with a resilient latching arm (44) extending rearwardly from a root end ( 45) integral with the body (36) adjacent the mating face and diverging away from the body (36) to a free end , a rearwardly facing latch shoulder (46) being formed on the plug (35 ) between the ends , a rearwardly facing stop surface (46) for the plug (35 ) being provided between the ends , the plug (35 ) being receivable in the cavity (16) by insertion through the mouth ( 17) along the insertion plane with resilient pivotal flexure of the latching arm (44) towards the body (36) until the stop surface (47) and shoulder (46) are juxtaposed , resilient movement of the latching arm (44) away from the body (36) bringing the stop surface (47) and shoulder (46) into latching engagement to latch the plug (35) in the fully inserted condition.

Inventors: HAYES EARL JAMES, SWENGEL ROBERT CHARLES JR, HAYES, EARL, JAMES, SWENGEL, ROBERT, CHARLES, JR.
Applicants: AMP INC, AMP INCORPORATED
Application year: 1985
Main classification: H01R31
IPC codes: H01R13