EP 0041260 B1 19840822 - SOUND ABSORBING ELEMENT UTILIZING THE EFFECT OF COINCIDENCE
Title (en)
SOUND ABSORBING ELEMENT UTILIZING THE EFFECT OF COINCIDENCE
Publication
Application
Priority
DE 3020830 A 19800602
Abstract (en)
[origin: EP0041260A1] 1. Absorption element based on the coincidence effect with a closed surface, characterized by 2 parallel coincidence wave guides with a periodic trapecoidal, corrugated or double-corrugated cross sections, where the areal moment of inertia, the young-moduls and the density of the wave guides, for example aluminium steel, carbon-fiber- plastics, glass-fiber-plastics chosen in such a manner, that for a given excitation frequency the bending wave velocity of the coincidence wave guide corresponds to the tracevelocity of the incidencing sound wave and where the enclosed space between the guides is gas proof sealed and filled with a gas of a high speed of sound such as hydrogen or helium and that for positioning of the coincidence wave guides separators are used.
IPC 1-7
IPC 8 full level
F16L 55/02 (2006.01); G10K 11/16 (2006.01)
CPC (source: EP)
G10K 11/16 (2013.01)
Designated contracting state (EPC)
AT FR GB IT
DOCDB simple family (publication)
EP 0041260 A1 19811209; EP 0041260 B1 19840822; AT E9119 T1 19840915; DE 3020830 A1 19811210
DOCDB simple family (application)
EP 81104147 A 19810530; AT 81104147 T 19810530; DE 3020830 A 19800602