GB1305174A - - Google Patents

Abstract

1305174 Mounting semi-conductor devices STANDARD TELEPHONES & CABLES Ltd 23 March 1971 7546/71 Heading H1K A number of wire leads, of enamelled copper, are moulded into a plastics body to lie within the body and to extend therefrom. The plastics body is treated in manufacture so as to provide a mounting area for a solid state device and adjacent areas at which the ends or sides of the wire leads are exposed to provide termihal points to which and to the device electrodes flying leads may be ultrasonically bonded. Fig. 11 shows the simplest case in which the ends of the wire leads are exposed at one face of the body 31 (and extend from the opposite face) and are connected by flying leads 34 to the device 33. Fig. 4 shows another construction. Its manufacture can best be understood by imagining the structure to be inverted. The wire leads 7 (then without the body 13) are wound by conventional coil-winding machinery to form a single-layer coil. (Adequate tension may be maintained by making the mandrel as two sprung apart halves, though this is not done in the particular embodiments.) Shuttering is then applied to the mandrel so that body 13 may be cast around the wire leads. The leads are then severed along a line opposite the moulded body and the structure removed from the mandrel. Now considering the drawing with the orientation shown, the top surface between the ribs 15 is slightly ground to different extents-in the contact area it is ground down to sever the wire leads and provide the device mounting area and in the two adjacent areas it is ground down sufficiently to expose the sides of the wire leads and to remove the enamelled insulation on the exposed sides. In a variant (Fig. 5, not shown), the wire leads are severed on the mandrel at the point adjacent the moulded body so that they project from one side of the body only. The central mounting area of the body is then left as a raised platform through which the wire leads pass, their sides being exposed by grinding down areas adjacent the mounting area as before but this time the same wire is exposed twice, once on each side of the mounting area.