Patent · US Expired

Electro-acoustic transducer unit

US4949387A · kind A · utility

10Cited by
0References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 8, 1989
Grant dateAug 14, 1990
Priority date
Expiry dateJun 8, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R2499/11
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An electro-acoustic transducer unit for use either as a microphone, a receiver or a voice frequency ringing transducer has a transducer plate fastened between bearing members provided with a piezo-electric layer. By carefully dimensioning the resonator chambers in front of and behind the transducer plate and providing one resonator space with a neck closed by a covering, which is removable, the transducer may be used as a receiver or a microphone or, by removal of the covering, may be used as a voice frequency ringing transducer. The transducer unit is particularly applicable as an electro-acoustic transducer in telephone technology.

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