Method for fabricating selectively plated electrical contacts

Claim 1

A continuous method of fabricating electrical contact members of the type wherein each member has a wear area adapted for mating engagement with another contact member to establish electrical connection therewith, and a terminal portion adapted to be joined to an electrical conductor, the method comprising the steps of: providing a long, thin, narrow, flexible spring metal tape of such dimensions that successive incremental lengths of the tape are adapted to act as plurality of interconnected contact blanks from which said contacts are punched, advancing said tape longitudinally in successive steps through the dies of a punch-press and punching at least one series of regularly spaced pilot holes therein, thereafter feeding said tape through a printing means by successive engagement of indexing means of the printing means with the pilot holes in the tape, and printing on resist material on both edges and both sides of said tape, with the printing on at least one side of said tape comprising a regularly recurring pattern of resist material characterized by at least one bare area surrounded by said resist material for each contact member to be produced corresponding to the wear area of each completed contact and located in precise spacial relationship to the aforesaid pilot holes in said tape, thereafter subjecting said tape to a selective plating process whereby a layer of a substantially inert, non-corrosive metal of a desired thickness is applied only to the bare areas of said tape, thereafter removing the printed resist material pattern from all areas on said tape, again advancing said tape longitudinally in successive steps through the dies of a punch-press, and subjecting each incremental length of said tape to at least one punching operation followed by at least one forming operation to form each contact member with a plated wear area in precisely fixed spacial relationship with respect to the pilot holes of said tape, whereby the plated wear area is precisely located with respect to the remaining portion of each contact member formed.