Speaker box
US12238474B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 2022 |
| Grant date | Feb 25, 2025 |
| Priority date | — |
| Expiry date | Oct 11, 2043 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2400/11
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides a speaker box including a housing, a sound unit and a magnetic circuit coupling valve. The sound unit includes a bracket, a vibration system and a magnetic circuit system including a secondary magnet. The housing includes a bottom cover having leakage holes. The magnetic circuit coupling valve is accommodated in a rear cavity and includes a support, a negative stiffness diaphragm and a coil. The negative stiffness diaphragm faces to the leakage holes. The coil receives an external control signal and generates an electromagnetic field with the secondary magnet to drive the negative stiffness diaphragm to seal the leakage holes, or make the leakage holes open, or make the leakage holes partially open or closed. Compared with a related technology, the speaker box has fine acoustic performance and is able to accurately control communication of a rear cavity with the outside.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.