Ferrofluid centered voice coil speaker
US7729504B2 · kind B2 · utility
17Cited by
6References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 30, 2007 |
| Grant date | Jun 1, 2010 |
| Priority date | — |
| Expiry date | Nov 21, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2400/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An audio speaker has a driver unit having a support frame with a central portion forming a magnetic structure defining an annular gap around a central magnetic post, a vibration system having a diaphragm and a voice coil, the voice coil is attached to one side of the diaphragm where the vibration system is fixed to the support frame and where the voice coil is movably mounted in the annular gap, and a magnetic fluid disposed in the annular gap only in a space between one side of the voice coil and a surface of the annular gap having a higher magnetic flux density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.