Magnetic structure for an ironless electrodynamic-loudspeaker motor, motors and loudspeakers
US8055010B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Sep 18, 2008 |
| Grant date | Nov 8, 2011 |
| Priority date | — |
| Expiry date | Mar 2, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2209/022
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic structure generating a magnetic field for an ironless motor of an electrodynamic loudspeaker having a mobile coil, wherein the magnetic structure generates a magnetic field in a gap in which the coil is arranged. The magnetic structure includes of a stack of three magnets corresponding to one intermediate magnet and two top and bottom covering magnets, the magnets forming a straight gap border and being located side by side, the intermediate magnet having a radial magnetic polarization, the covering magnets having identical magnetic polarizations and remanent magnetizations. The covering magnets have a radial or axial magnetic polarization. When magnetic polarization of the covering magnets is radial, remanent magnetization of each covering magnet is higher than remanent magnetization of the intermediate magnet, and when magnetic polarization of the covering magnets is axial, remanent magnetization of each covering magnet is lower than remanent magnetization of the intermediate magnet. Motors are provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.