Audio playback device
US9420377B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2013 |
| Grant date | Aug 16, 2016 |
| Priority date | — |
| Expiry date | Aug 28, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2499/11
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An audio playback device is provided. The audio playback device includes a magnetic module, an annular armature, a coil module and a diaphragm. The magnetic module includes a magnetic source and two yokes each connected to one of two magnetic poles generated by the magnetic source and extends to form a magnetic field. The annular armature includes a first, a second, a third and a fourth arms that form a hollow area. At least part of the first arm is located in the magnetic area. The coil module is winded on the second arm and generates two varying electro-magnetic poles according to an alternating current data signal. The annular armature vibrates according to a relation of the two varying electro-magnetic poles and the magnetic field. The diaphragm is connected to the annular armature through a driving rod to vibrate according to the annular armature to generate a sound wave.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.