Audio speaker with graduated voice coil windings
US7492918B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 17, 2004 |
| Grant date | Feb 17, 2009 |
| Priority date | — |
| Expiry date | Oct 28, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R9/04
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An audio speaker driver having a voice coil with graduated windings such that different sections of the voice coil have different electrical resistances and/or lengths per unit of height of the voice coil. A center portion of the voice coil gives a greater BL, while outer portions give lower overall electrical resistance, such that the audio speaker driver is highly efficient and linear during low excursion operation, with a smoother transition from the linear region to the grossly non-linear region. The wire of the graduated voice coil can have varying cross-sectional area over its length, can be wound on varying on-center spacing, can be wound in different numbers of layers in the various sections, and/or it can fork into interlaced, parallel windings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.