EP 0680031 A3 19951115 -
Publication
Application
Priority
DE 4414566 A 19940427
Abstract (en)
[origin: EP0680031A2] The acoustic damper has at least two cavities (4,5) formed by pressing tapering recesses into a close cell plastics foam. The cavities are open to the sound source and are covered by removable perforated plates (9,10) with the hole size and spacing designed to provide the damping effect. The perforated plates are metal and have a clip fastening to the cavities for cleaning. The cavities have different resonant frequencies either by virtue of different sizes or by having different spatial holes patterns in the cover plates. The resonators are mounted in ceiling fixtures. <IMAGE>
IPC 1-7
IPC 8 full level
H04R 1/34 (2006.01); G10K 11/16 (2006.01); G10K 11/172 (2006.01)
CPC (source: EP US)
G10K 11/172 (2013.01 - EP US)
Citation (search report)
- [AD] EP 0454949 A2 19911106 - FREUDENBERG CARL FA [DE]
- [A] US 2904125 A 19590915 - BOURNE ROLAND B, et al
- [A] EP 0317380 A1 19890524 - THOMSON CSF [FR]
- [A] EP 0246464 A1 19871125 - PAPE HANS [DE], et al
Designated contracting state (EPC)
CH FR GB LI SE
DOCDB simple family (publication)
EP 0680031 A2 19951102; EP 0680031 A3 19951115; EP 0680031 B1 19990616; DE 4414566 A1 19951102; DE 4414566 C2 19971120; JP 2986711 B2 19991206; JP H0844370 A 19960216; US 5587564 A 19961224
DOCDB simple family (application)
EP 94117818 A 19941111; DE 4414566 A 19940427; JP 9897095 A 19950424; US 41968795 A 19950410