EP 0405581 A1 19910102 - Sound absorber.
Title (en)
Sound absorber.
Title (de)
Schallabsorbierendes Paneel.
Title (fr)
Panneau absorbant les sons.
Publication
Application
Priority
JP 16914089 A 19890630
Abstract (en)
A sound absorber body (1) includes a plurality of cell-like spaces (3) defined by walls (2), whose ends are open at a sound absorption side and closed at the other side. The cell-like spaces have different lengths, and part of the cell-like spaces having longer lengths are bent so as to be disposed behind adjacent shorter cell-like spaces. Arrangement of the lengths of the cell-like spaces may be determined in accordance with a two-dimensional quadratic residue series with modulo of a prime number.
IPC 1-7
IPC 8 full level
G10K 11/16 (2006.01); E04B 1/84 (2006.01); G10K 11/172 (2006.01)
CPC (source: EP)
E04B 1/8404 (2013.01); G10K 11/172 (2013.01); E04B 2001/848 (2013.01)
Citation (search report)
- [X] FR 2214932 A1 19740819 - LOCKHEED AIRCRAFT CORP [US]
- [Y] US 1972563 A 19340904 - RICHARD IRVIN
- [Y] US 3693750 A 19720926 - TAKKUNEN PHILIP D
- [Y] US 4384020 A 19830517 - BEGGS STANLEY L, et al
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
EP 0405581 A1 19910102; EP 0405581 B1 19931027; DE 69004166 D1 19931202; DE 69004166 T2 19940421; JP 2933322 B2 19990809; JP H0333897 A 19910214
DOCDB simple family (application)
EP 90112461 A 19900629; DE 69004166 T 19900629; JP 16914089 A 19890630