Patent · US Expired

Electric keyboard of snap-contact type

US4200778A · kind A · utility

11Cited by
4References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 19, 1978
Grant dateApr 29, 1980
Priority date
Expiry dateMay 19, 1998

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H13/36
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A keyboard comprises a plurality of keys which, when depressed, elastically deform conductive laminae which thereby go with a snap action from a stable configuration to an unstable configuration to complete an electrical circuit associated thereto. Each lamina has the form of two mutually transverse pairs of parallel edge strips spanned by a diagonal strip and the edge strips have permanent bends set into them such that the diagonal strip is bowed in the stable configuration towards the corresponding key. A fixed contact on the lamina is located adjacent one end of the diagonal strip and a movable contact is located in the central region of the diagonal strip. A single key actuates two identical laminae, one through an actuator resiliently coupled to the key and the other through an actuator fixed to the key.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.