EP 0029898 A3 19810826 - VARIABLE RESONATORS FOR NOISE ATTENUATION
Title (en)
VARIABLE RESONATORS FOR NOISE ATTENUATION
Publication
Application
Priority
DE 2947026 A 19791122
Abstract (en)
[origin: US4325461A] A noise reducing resonator, herein referred to as a silator due to its noise silencing quality, is made up of primary struts forming a main frame and secondary struts forming at least one subframe enclosed by a vacuum tight cover to enclose a vaulting evacuated volume. Each frame has a given span width and a vaulting height corresponding to 0.005 to 0.05 times the respective span width. The frames are arranged in a hierarchic order which means that a larger main frame holds a smaller subframe which in turn holds a still smaller subframe and so on. The resonance frequency increases with the number of subframes held in a main frame. Interconnected silators may cover entire surface areas for noise reduction or absorption.
IPC 1-7
IPC 8 full level
G10K 11/16 (2006.01); G10K 11/172 (2006.01)
CPC (source: EP US)
G10K 11/172 (2013.01 - EP US)
Citation (search report)
US 3773141 A 19731120 - THIEN G, et al
Designated contracting state (EPC)
AT CH FR GB IT NL
DOCDB simple family (publication)
US 4325461 A 19820420; AT E13232 T1 19850515; DE 2947026 B1 19801127; DE 2947026 C2 19811001; EP 0029898 A2 19810610; EP 0029898 A3 19810826; EP 0029898 B1 19850508
DOCDB simple family (application)
US 20592280 A 19801112; AT 80106229 T 19801014; DE 2947026 A 19791122; EP 80106229 A 19801014