Patent · US Expired

Switches and keyboards

US4634818A · kind A · utility

26Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 1985
Grant dateJan 6, 1987
Priority date
Expiry dateSep 26, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H2229/042
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A low profile switch or keypad has one or more touch pads (14) formed integrally with and raised from a surrounding membrane or key mat (15) of elastomeric material by a wall (30) of resiliently deformable material of thickness and angle relative to the mat (15) so that the wall (30) can flex under finger pressure on the or each pad (14) without deflecting the surrounding membrane. The underside of each pad (14) is formed with a convex contact pad (29) dimensioned in relation to the pad diameter and travel and the length of wall (30) so that the pad (29) makes surface to surface contact with conductors (12), (13) of an underlying circuit board (10). The mat (15) is held in tension to the board (10) fits. The keyboard uses only two interfitting parts and needs no bezel but provides a tactile response to key depression.

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