Magnetic membrane suspension
US7940953B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 2007 |
| Grant date | May 10, 2011 |
| Priority date | — |
| Expiry date | Mar 6, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R13/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An electro-acoustic transducer has a membrane comprises a folded or curved sheet of film material. A frame supports the membrane in at least an upper end thereof. A resilient suspension connects the upper ends of the membrane to the frame. A driver system is attached to the frame and the membrane for moving the membrane dependent on an electrical input signal. At least one ferromagnetic element is arranged in the membrane or on one of the surfaces of the membrane at its lower end. At least one magnet provides a magnetic field, the magnet being attached to the frame in a position adjacent the lower end of the membrane. The ferromagnetic element is pulled down by a magnetic force between the element and the magnet establishing a gap therebetween such that tensioning of the membrane is achieved by the magnetic force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.