Selective sound transmission and active sound transmission control
US11164559B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2018 |
| Grant date | Nov 2, 2021 |
| Priority date | — |
| Expiry date | Nov 11, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/34
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
Passively controlled acoustic metamaterials allow transmission of low amplitude acoustic (sound) waves having a resonance frequency and reflect waves having a substantially different frequency. Such materials also reflect waves having the resonance frequency when those waves have an amplitude exceeding a threshold. High amplitude resonance waves cause a resonance membrane contained in unit cells of the metamaterial to contact a rigid structure that is positioned at a longitudinal constraint distance from the resonance membrane in each unit cell. Such contact changes the resonance frequency of the membrane, thereby causing reflection of high amplitude waves. Actively controlled acoustic metamaterials include a ferromagnetic layer on the membrane and an electromagnetic positioned in each unit cell. Activation of the electromagnetic displaces the membrane and thereby shifts the resonance frequency of the membrane, on demand.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.