Electrical contact member having low electrical resistance

Abstract

Abstract An improved contact element is disclosed useful particularly as a contact element bridging at least two stationary contacts. A layer of metal having high electrical conductivity is disposed on selected locations of an electrically conductive disc in alignment with the stationary contacts. Such discs having selectively disposed metal layers are useful for example in low voltage, low current applications wherein contact resistance is preferably kept to a minimum, as in hand held calculators. To form such discs with selectively plated portions, a strip of electrically conductive material, such as a stainless steel is fed from a coil to a first station in which the discs are partially punched from and guide holes are formed in the strip. The strip is then fed intermittently through a series of stations which include degreasing, cleaning, activating, striking, actuating, plating, rinsing and drying and then is recoiled. The selective plating is effected by using a cored mask which moves into contact with the strip each time the strip stops at which time the plating solution is pumped into the mask against the stainless steel substrate and a voltage is applied to the substrate to effect the plating. The mask is dimensioned such that a plurality of discs, e.g. eighteen, are plated at each stationary interval. The selectively plated strip is paid off and the discs are formed with a curved surface and severed from the strip into individually formed snap acting discs ready for use.

Inventors

• 👤 Laurence J. Keough

Bibliographic Details