EP 2071561 A3 20170517 - Absorbent structure for reducing the noise generated in particular by a rotor and fairing comprising such a structure
Title (en)
Absorbent structure for reducing the noise generated in particular by a rotor and fairing comprising such a structure
Title (de)
Schallabsorptionsstruktur zum Dämpfen von Geräuschen, die hauptsächlich durch einen Rotor erzeugt werden, und eine solche Struktur umfassende Verkleidung
Title (fr)
Structure absorbante pour l'atténuation de bruits générés notamment par un rotor et carénage comportant une telle structure
Publication
Application
Priority
FR 0708699 A 20071214
Abstract (en)
[origin: EP2071561A2] The structure has a separation unit for arranging a porous wall (4) at fixed distance from a rigid baffle (1) made of glass fiber by defining cavities (3) with a height (h1) between the porous wall and the baffle, where the height is determined to obtain maximum absorption of acoustic waves emitted at basic frequency. An additional porous wall is arranged in the cavities at intermediate height to obtain maximum absorption for another basic frequency. The porous walls have an absorbent layer made of fine-mesh fence and another absorbent layer made of fiber felt.
IPC 8 full level
G10K 11/172 (2006.01)
CPC (source: EP US)
G10K 11/172 (2013.01 - EP US)
Citation (search report)
- [XYI] EP 1111584 A1 20010627 - EADS AIRBUS SA [FR]
- [Y] US 6114652 A 20000905 - CLARKE JAMES A [US], et al
- [Y] FR 2674362 A1 19920925 - GRUMMAN AEROSPACE CORP [US]
- [Y] FR 2482663 A1 19811120 - ROLLS ROYCE [GB]
- [Y] DE 29512787 U1 19951012 - DUERR METALLTECHNIK [DE]
- [A] US 2006219477 A1 20061005 - AYLE EARL [US]
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR
Designated extension state (EPC)
AL BA MK RS
DOCDB simple family (publication)
EP 2071561 A2 20090617; EP 2071561 A3 20170517; EP 2071561 B1 20210203; CA 2646933 A1 20090614; CA 2646933 C 20130521; CN 101458926 A 20090617; CN 101458926 B 20120704; FR 2925208 A1 20090619; FR 2925208 B1 20160701; JP 2009145891 A 20090702; US 2009152395 A1 20090618; US 7779965 B2 20100824
DOCDB simple family (application)
EP 08020965 A 20081203; CA 2646933 A 20081210; CN 200810186825 A 20081212; FR 0708699 A 20071214; JP 2008316313 A 20081212; US 33061008 A 20081209