Patent · US Expired

Laminated piezoelectric keyboard

US4857887A · kind A · utility

57Cited by
9References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 5, 1988
Grant dateAug 15, 1989
Priority date
Expiry dateOct 5, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K17/9643
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

The keyboard comprises piezoelectric crystal elements arranged between laminates provided with conducting strips. A voltage is generated when pressure is applied to the elements. The keyboard is tensionless in its rest state and contains no unwanted air spaces.

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