Electric rocking mode damper
US9749742B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 2016 |
| Grant date | Aug 29, 2017 |
| Priority date | — |
| Expiry date | Jul 19, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R9/041
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention relates to a new audio transducer for mobile devices, in particular a micro speaker for use in mobile phones, tablets, gaming devices, notebooks or similar devices, that comprises two figure-8 shaped coils to compensate tumbling passively or to detect and compensate actively rocking modes of the membrane along the two axes perpendicular to the axis of piston-wise movement of the membrane using a detection coil and a damping coil per axis. An amplifier may be used to amplify the detection signal in order to increase the damping effect. Electrical rocking mode compensation replaces state of the art damping mechanisms which are based on damping materials added in the moving part of the membrane. Due to the independence of environmental conditions electrical damping outperforms existing damping techniques.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.