Double-domed elastomeric keyboard element
AssigneeInternational Standard Electric Corporation
InventorReinhard Deeg
Life of this patent
Estimating the term…
Abstract
A double-domed elastomeric keyboard element is disclosed in which a solid contact disc is connected to the junction of the domes of the keyboard element housing. The inner dome is provided on its inside with a downwardly extending projection which engages the contact disc when the keyboard element is depressed to press the disc against a pair of conductors on a printed circuit board below the element. Because of the non-positive connection between the key plunger and the conductors, the contact pressure is almost equal to the operating force.
Claims4
In a keyboard element having a hollow double-domed elastomeric housing including an upper dome and a lower dome of greater diameter than said upper dome, said domes intersecting at an annular junction, and a conductive elastomeric moving contact member mounted inside said housing connected to said junction, said moving contact member being adapted to bridge conductors on a substrate below said housing, the improvement which comprises:
- a projection extending downwardly from an upper region of said upper dome over said moving contact member;
- and
- said moving contact member embodying an upwardly facing supporting surface engageable by said projection.
Dependencies are inferred from the claim text.