Patent · US Expired

Membrane keyboard blockout apparatus

US4820887A · kind A · utility

12Cited by
4References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 2, 1988
Grant dateApr 11, 1989
Priority date
Expiry dateMay 2, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2221/068
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A membrane keyboard blockout apparatus for a keyboard having an array of a plurality of flexible key members in respective ones of a plurality of apertures arranged in a grid forming the keyboard includes a cover plate dimensioned to span a flexible key member and to provide a tight fit within an aperture defining a key member. The cover plate has a thickness providing a substantially inflexible configuration in response to normal operator manipulation and a plurality of corner support pedestals contacting respective corners of the flexible key member when the cover plate is inserted in a key member aperture. Thus, the pedestals provide a support between the cover plate and the flexible key member at the edges of the key member to preclude, in combination with the inflexible structural characteristic of the cover, an actuation of the flexible key member under the cover.

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