Patent · US Expired

Induction speaker

US5062140A · kind A · utility

27Cited by
7References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 18, 1989
Grant dateOct 29, 1991
Priority date
Expiry dateApr 18, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R2209/043
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In a speaker which comprises a diaphragm having a vibrating portion and an annular conductive portion, a current feeding coil facing the conductive portion with a predetermined gap therebetween, and a magnetic circuit including a top plate, a magnet and a yoke plate to which the current feeding coil is attached; the diaphragm is formed so that an electrical resistance of its conductive portion is lower than an electrical resistance of its vibrating portion.

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