Switch Contact Element and Its Preparation Method

摘要

A switch contact element, having a layered structure comprising three layers: the bottom layer is silicone rubber, the middle layer is a continuous base metal sheet layer, and the upper layer is a discontinuous (stripe-shaped, raised-point-shaped or lattice-shaped) precious metal plated layer or a double-metal composite layer of a discontinuous base metal plated layer and a precious metal plated layer. The thickness of the bottom layer is greater than that of the middle layer, the thickness of the middle layer is greater than that of the upper layer, and the thickness of the upper layer meets the conditions that the conductive current is greater than safe current of conductive contacts on a circuit board, and the service life of a switch for the design is ensured.

主权项

1. A switch contact component,
wherein the switch contact component is
used as switch conducting contact,capable of connecting two or more conducting contacts and switching on the circuit board, being a small cylindrical, elliptical or prismatic disk with having a thickness of 0.5-8 mm and a cross sectional area of 0.8-80 mm2,and being structured in three layer lamination, comprising a under layer, which is a rubber (1); a continuous base metal sheet, sandwiched as a mid layer (2); a upper layer, a striped, convex dotted or latticed precious metal plating or a bimetallic composite layer formed with a striped, dotted or latticed base metal plating (3) and a precious metal plating (4); and said base metal plating (3) is sandwiched between the mid layer (2) and the precious metal plating (4); wherein said base metal material is selected from copper, nickel, titanium, aluminum, zinc or iron, or any alloy of them, or a laminated composite containing any of them or their alloys; wherein said precious metal plating material is selected from gold, silver, ruthenium, rhodium, palladium, osmium, iridium or platinum, or any of their alloys; wherein width of each stripe (5) is 0.05-2 mm, the stripes are spaced at intervals of 0.2-2 mm; each interval is smaller than a minimum spacing of any two contacts on the corresponding circuit board; wherein said convex dots (6) are similar to cylinders or prisms, and the diameters of their top surfaces or circumferences are 0.2-2 mm, and spacing between the adjacent convex dots (6) is 0.05-1 mm, and the spacing between adjacent dots is smaller than a half of a minimum spacing of any two contacts on the corresponding circuit board, to ensure more than two convex dots (6) to get in touch with the conducting contact on the other circuit board simultaneously; wherein latticed lines (7) is 0.05-2 mm wide, and the a void (8) area between the lattice lines is 0.05-5 mm2; wherein a upper layer thickness satisfies the following condition: in case of stripes, the stripe (5)'s minimum width×thickness>2×10−4 mm2; in case of dots, the convex dots (6) bottom circumference diameter×thickness>1×10−4 mm2.