Back to results
US 4,859,820 AGranted
Quiet key switch
AssigneesAmerican Telephone and Telegraph Company, AT&T Information Systems Inc.
InventorsCasimer Gotfryd, Stephen L. Kay, Hartland P. Klotz, Robert M. Wentzel
Life of this patent
Estimating the term…
Abstract
A key switch utilizing a buckling compression spring to move a switch actuator mechanism includes a cylindrical core of resilient material located within an opening formed by the coils of the compression spring to attenuate the acoustical energy generated by the buckling and unbuckling action of the spring.
Claims6
In a key switch acutating mechanism comprising:
- a key top;
- a housing having means for slidably receiving said key top for vertical motion thereof;
- a pivoting rocker means located in said housing opposite said key top;
- a buckling compression spring including coils forming a cylindrical opening, said spring mounted between said key top and said pivoting rocker means, the spring buckling and unbuckling in response to the downward and upward motion of the key top, respectively, the spring generating acoustical energy by the buckling and unbuckling action of the spring which energy manifests itself in at least two distinct types of sounds--metallic click and metallic ringing;
- and
- means for damping acoustical energy generated by the spring which manifests itself by the sound of metallic ringing.
3 more elements
Dependencies are inferred from the claim text.