Keyboard switch assembly having movable contact, and supporting helicline type legs disposed co-planar to common conductive sheet

摘要

A switching device having a movable contact element characterized by a set of unconnected, curved slots radiating outward from a central key area and equally spaced around the central key area. The radially extending unconnected, curved slots may be sections of a spiral, at least some of which sections overlap each other. Adjustment of the spring rate of the movable contact element is accomplished by adjusting the length of the slots or by regulating the distance of the inner terminus of the slots from a central point of the central key area. The movable contact element either contacts a second contact element for contact switching or approaches the second contact element for capacitive switching.P PA plurality of the switching elements can be formed in a planar array on a continuous metallic substrate to provide a keyboard. The movable switching elements can be formed on the metallized areas of a printed circuit board.