Patent · US Expired

Keyboard switch apparatus for electronic musical instrument

US4733590A · kind A · utility

17Cited by
10References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 21, 1985
Grant dateMar 29, 1988
Priority date
Expiry dateNov 21, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S84/07
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A keyboard switch apparatus for an electronic musical instrument has first, second and third layers, and first and second switches. The second layer has elasticity and is separated from the first layer. The third layer has elasticity and is inserted between the first and second layers at a distance therefrom. The first switch consists of conductors respectively formed on opposite surfaces of the second and third layers. The second switch consists of conductors respectively formed on opposite surfaces of the first and third layers. The second and third layers are sequentially urged and deformed by an actuator interlocked with key depression. The first and second switches are sequentially closed. A time requred for closing the first switch is different from that for closing the second switch. The closure time difference corresponds to a key depression speed, which is used to generate a signal corresponding to the depression speed, and a musical tone signal corresponding to the depression speed.

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