Double layer attenuation panel with two layers of linear type material
US4294329A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1979 |
| Grant date | Oct 13, 1981 |
| Priority date | — |
| Expiry date | Dec 17, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24331
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A double degree acoustic attenuation sandwich panel having a plurality of stacked components adhered together to form a unitary sandwich structure. The structure comprising an impervious facing of thin sheet material, a first honeycomb core with end wise directed cells, a first perforate facing of thin sheet material, a first thin layer of porous fibrous material, a second perforated facing of thin sheet material, a second honeycomb core with end wise directed cells, a third perforate facing of thin sheet material, the second perforated facing sheet having substantially larger perforations than the first and third sheets, and a second layer of porous fibrous material. The resulting sandwich panel has a pre-determined flow through resistance between the outer surface of the first and second layers of porous fibrous material and the cells of the first and second honeycomb cores. The cells of the first and second honeycomb cores may be of equal or different volume and may be constructed of similar or dis-similar materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.