Patent · US Expired

Multifunction acoustic device

US6744904B2 · kind B2 · utility

4Cited by
20References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 6, 2001
Grant dateJun 1, 2004
Priority date
Expiry dateSep 6, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04R2400/03
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A speaker vibrating plate having a voice coil secured thereto is provided in a frame, a rotor having poles is rotatably supported in the frame, and a stator having poles is provided in the frame. A permanent magnet is provided in the rotor for forming a magnetic circuit passing through the rotor and the stator, and a stator coil is provided in the stator. A driving circuit is provided for energizing the stator coil for rotating the rotor.

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