ADAPTABLE TERMINAL ASSEMBLY FOR MULTI-CONTACT ELECTRICAL CONNECTOR

Abstract: A terminal assembly is composed of terminals (12) arranged alongside a terminal carrier (11) comprised of a series of integral, symmetrical, shaped structures, with angular projections (16, 17) at a predetermined pitch (Da) along the carrier (11). Lozenge-shaped through holes (13) are formed in the centres of the structures. To alter the pitch of the terminals (12) the projections (16, 17) are exposed to deformation force prior to assembly of a connector.

Description: FIELD OF THE INVENTION The present invention relates to a terminal assembly having a row of terminals supported at a predetermined pitch along one longitudinal side of a terminal carrier. BACKGROUND OF THE INVENTION A terminal assembly, used, for example, to manufacture a multi-contact electrical connector, is generally formed by punching out, at a predetermined pitch non-required portions of a belt-like conductive plate or substrate, leaving a longitudinal region on one side of the substrate substantially intact as a carrier for the terminals thus formed. In assembling a multi-contact electrical connector, the contact terminals of the terminal assembly are simultaneously set in the housing of a connector while they are still supported by the terminal carrier. Once set, the terminals are then separated from the terminal carrier. Because this particular method of assembly has proven more efficient than that wherein the terminals are separated from the supportive carrier and then set in the housing of the connector individually it is more widely used. This method of assembly, however, necessitates that, even if the terminals are of the shame shape, when two types of connectors with different terminal pitches of e.g. 2.0 mm and 2.54 mm, are required separate terminal assemblies must be prepared to accommodate the different pitches. This problem is common in terminal assemblies for IC pins (IC LEG), IC socket terminals, "Griplet" terminals (trademark of E I DU PONT DE NEMOURS AND COMPANY, U.S.A.) US-A-3955877 describes a terminal assembly or header stamped or cut from a section of flat stock material and providing a series of spaced-apart terminals along one side of a carrier region which is provided with holes for driving engagement with sprockets as well as V-shaped notches open from one of the major surfaces thereof which provide some flexibility for adjustment of the spacing between the terminals. SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved terminal assembly having a variable terminal pitch. As is known from US-A3955877, a terminal assembly constructed in accordance with the invention is in the form of a conductive plate with an elongate terminal carrier composed of a series of integral, shaped apertured structures which provide a series of projections arranged at predetermined pitch therealong and a series of terminals supported by the carrier extending from either side of each of the projections along one side of the terminal carrier, the terminals having a pitch corresponding to that of the projections. In accordance with the invention, the plate is flat and the projections are composed of longitudinal sides of the structures which can be subjected to deformation force to cause the projections to move transversally of the carrier to alter the pitch of the terminals. The projections are usually angular and symmetrical both along the carrier and transverse thereto. To increase the pitch of the terminals the projections can be subjected to uniform compressive force directed inwardly of the carrier. The structures may be diamond shaped each with four equal sides and two obtuse angles between the sides which form the projections and lozenge shaped holes which are aligned with the centres of the diamond shaped structures. The deformation force closes the openings and lengthens the diamond shaped structures. The terminal assembly can be made by feeding a conductive metal plate longitudinally in steps of constant predetermined pitch (Da), forming pilot holes in one side margin of the plate with the predetermined pitch (Da), cutting out portions in the side margin of the plate opposite the holes to define projections along one edge of said side margin and terminals with the same predetermined pitch (Da) disposed between the projections and cutting out further portions in the one side margin with the same predetermined pitch (Da) to provide further projections along another edge of the side margin and to create a series of shaped structures defined by the projections which serve as a deformable carrier for the terminals. In another aspect the invention provides a method of assembling a multi-contact electrical connector, utilizing a terminal assembly as aforesaid, wherein the terminals have a predetermined pitch (Da) and the connector requires contacts with a selectable pitch of at least Da or Db where Db > Da and comprising setting the terminals in a housing of the connector and thereafter separating the terminals from the carrier of the assembly and adjusting the pitch of the terminals, if desired, from Da to Db by subjecting the projections of the carrier to deformation force to cause the projections to move transversally of the carrier prior to setting the terminals in the housing. The invention may be understood more readily and various other aspects and features of the invention may become apparent from consideration of the following description. BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein:- Fig. 1 is a perspective view of a terminal assembly constructed in accordance with the present invention; Fig. 2 is a plan view of the terminal assembly of Fig. 1; Fig. 3 is a plan view, corresponding to Fig. 2, which shows the terminal assembly after the terminal pitch alteration; and Figs. 4a to 4c illustrate sequential steps in the manufacture of the terminal assembly of Figs. 1 and 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Figs. 1 and 2 depict a terminal assembly produced from a conductive metal strip or plate in a manner described hereinafter. The terminal assembly has a narrow apertured side margin forming a belt-like terminal carrier 11 for a row of spaced terminals 12. The carrier 11 is composed of a series of symmetrical integral, diamond-shaped structures with four equal sides and two obtuse angles whose apices form a series of projections or protuberances arranged at a predetermined pitch Da along the opposite longitudinal sides of the terminal carrier 11. The first projections of the structures at the side of the carrier 11 from which terminals 12 extend are denoted by reference number 16 and the second projections at the opposite side of the carrier 11 are denoted by the reference number 17. Lozenge-shaped holes 13 are formed in the carrier 11 and are aligned with the centres of the diamond-shaped structures at the points of intersection between transverse axes 14, and a central longitudinal axis 15 of the carrier 11. The obtuse angles of the holes 13 have the same pitch Da. The terminals 12, extend from the carrier 11 at either side of each of the projections 16 and have the same pitch Da as shown in Fig. 2. The terminal assembly as described can be used with connectors requiring a contact pitch of Da but the plan view of Fig. 3 shows the assembly adjusted to the terminal pitch Db. In order to increase the pitch between the terminals 12 from Da to Db, a substantially uniform compressive force is applied to the projections 16 and 17 by means of a simple device (not shown). In this manner the obtuse angles of the diamond-shaped structures are increased to tend to straighten the longitudinal sides of the diamond-shaped structures and close the lozenge-shaped holes 13. As a result, the pitch of respective contact terminals 12 is increased by ΔD from Da to Db. The variations in the pitch of terminals 12 is directly related to the extent to which the obtuse angles forming the projections 16 and 17 are deformed. Let it be assumed that the symbol La represents the peripheral length of each lozenge-shaped hole 13, and that the symbol Lb denotes the length of the axial line 15 from one point of its bisection of an angle of a hole 13 to the other. Using these two symbols, the maximum value, ΔDmax, of adjustment factor ΔD can be represented as (La/2)-Lb. The pitch of the contact terminals 12 of the terminal assembly of Fig. 1 and 2 can thus be varied within the range of from Da to Da+ΔDmax dependent upon the extent to which the diamond-shaped structures are deformed. The terminal assembly embodying this invention can be adapted to suit various types of electrical connectors wherein the terminal pitch varies within the range between Da and Da+ΔDmax. There is moveover no need to separate the contact terminals 12 from the terminal carrier 11 in advance of setting them in the housing of a connector. A method of manufacturing the terminal assembly will now be described with reference to Figs. 4a to 4c. The leading end of a belt-like conductive metal plate 20 is fed into a progressive die (not shown) by a feeder (not shown) at the substantially constant prescribed pitch steps Da. In the first stage of the progressive die, pilot holes 21 are formed in one side margin of the plate 20, as shown in Fig. 4a. These pilot holes 21, spaced apart by Da, are used as a locating means to compensate for errors in the pitch at which the feeder carries plate 20 forward. As shown in Fig. 4b, in the second stage of the progressive die, portions 22 of the metal plate 20, at one side of the pilot holes 21 are punched out in alignment with the pilot holes 21 to leave the contours of the first projections 16 and the contact terminals 12. As shown in Fig. 4c, in the third stage of the progressive die, portions 23 of the plate 20 at the other side of the pilot holes 21 are punched out in alignment with the pilot holes 21 to define the projections 17 and the lozenge-shaped portions surrounding the pilot holes 21 are punched out of the metal plate 20 to provide the holes 13. This invention is not limited to the embodiment described above and various modifications can be made. For instance, the shape of the through hole 13 need not be limited to that of a lozenge, but may, instead, be, for example, eliptical. It is preferred however that the width of each through hole 13 across the terminal carrier 11, be greatest near the central portion of the hole, that is the portion defined by the intersection of imaginary axes 14 and 15. Modifications to the shape of the sides of the device are also permissible. Rather than being angular, the sides could, for example, just as well be arcuate. The invention is also applicable to terminal assemblies for manufacturing not only electrical connectors but also IC pins (IC LEG), IC socket terminals and "Griplet" terminals (trademark of E I DU PONT DE NEMOURS AND COMPANY, U.S.A.),.

Claims: A terminal assembly in the form of a conductive plate with an elongate terminal carrier (11) defined by a series of integral, shaped, apertured structures which provide a series of projections (16, 17) arranged at predetermined pitch therealong and a series of terminals (12) supported by the carrier (11) extending from either side of each of the projections (16) along one side of the terminal carrier (11), the terminals (12) having a pitch corresponding to that of the projections (16); characterized in that the plate is flat and the projections (16, 17) are composed of longitudinal sides of the structures which can be subjected to deformation force to cause the projections to move transversally of the carrier to alter the pitch of the terminals (12). A terminal assembly according to claim 1, wherein the projections (16, 17) have the same shape and are symmetrical with respect to the longitudinal axis of said terminal carrier. A terminal assembly according to claim 2, wherein the projections (16, 17) are also symmetrical with respect to transverse axes of the structures. A terminal assembly according to claim 3, wherein the structures have through holes (13) which are symmetrical with respect to the longitudinal and transverse axes of the structures constituting the terminal carrier. A terminal assembly according to claim 4, wherein the width of each through hole, transversely of the terminal carrier, is greatest near the central portion. A terminal assembly according to claim 4 or 5, wherein each through hole (13) is lozenge-shaped. A terminal assembly according to any one of claims 1 to 6, wherein the projections are angular. A terminal assembly according to claim 1, wherein the structures are diamond shaped each with four equal sides and two obtuse angles between the sides which form the projections and lozenge shaped holes (13) are provided which are aligned with the centres of the diamond shaped structures and the deformation force closes the openings and lengthens the diamond shaped structures. A method of assembling a multi-contact electrical connector, utilizing a terminal assembly in accordance with any one of the predetermined claims wherein the terminals have a predetermined pitch and the connector requires contacts with aa selectable pitch of at least Da or Db where Db > Da and comprising setting the terminals in a housing of the connector and thereafter separating the terminals from the carrier of the assembly; and adjusting the pitch of the terminals, if desired, from Da to Db by subjecting the projections (16, 17) of the carrier (11) to deformation force to cause the projections to move transversally of the carrier prior to setting the terminals in the housing. A method of making a terminal assembly as claimed in claim 1 comprising feeding a conductive metal plate (20) longitudinally in steps of constant predetermined pitch (Da), forming pilot holes (21) in one side margin of the plate with the predetermined pitch (Da), cutting out portions (22) in the side margin of the plate opposite the holes (21) to define projections (16) along one edge of said side margin and terminals (12) disposed between the projections with the same predetermined pitch (Da) and cutting out further portions (13, 23) in the one side margin with the same predetermined pitch (Da) to provide further projections (17) along another edge of the side margin and to create a series of shaped structures defined by the projections (16, 17) which serve as a deformable carrier for the terminals.

Inventors: TAKAHASHI, FUMIYUKI
Applicants: E.I. DU PONT DE NEMOURS AND COMPANY
Application year: 1986
Main classification: H05K7
IPC codes: H01R43, H05K7