EP 0421233 A3 19920812 - DEVICE FOR PREVENTING THE PENETRATION OF FOREIGN BODIES IN A SOUND TRANSDUCER
Title (en)
DEVICE FOR PREVENTING THE PENETRATION OF FOREIGN BODIES IN A SOUND TRANSDUCER
Publication
Application
Priority
US 41738989 A 19891005
Abstract (en)
[origin: US4953215A] In an arrangement to prevent the intrusion of foreign matter into a transducer which extends with a projection provided with an opening into a sound channel of a hearing aid, a reduced need for space as well as simpler construction, compared with the state of the art, are achieved by means of the following characterizing features: A membrane made of pore-free material is provided, which has at least one bore for the passage of sound of from a few hundredths to a few tenths of a millimeter diameter, and in which the wall thickness of the membrane is small with respect to the diameter of the bore.
IPC 1-7
IPC 8 full level
H04R 25/00 (2006.01)
CPC (source: EP US)
H04R 25/654 (2013.01 - EP US)
Citation (search report)
- [A] DE 3540579 A1 19870527 - TOEPHOLM & WESTERMANN [DK]
- [A] US 4553627 A 19851119 - GASTMEIER WILLIAM J [CA], et al
- [A] US 3852540 A 19741203 - DIETHELM B
Designated contracting state (EPC)
AT CH DE DK FR GB IT LI NL
DOCDB simple family (publication)
US 4953215 A 19900828; AT E108051 T1 19940715; DE 59006302 D1 19940804; DK 0421233 T3 19941107; EP 0421233 A2 19910410; EP 0421233 A3 19920812; EP 0421233 B1 19940629
DOCDB simple family (application)
US 41738989 A 19891005; AT 90118347 T 19900924; DE 59006302 T 19900924; DK 90118347 T 19900924; EP 90118347 A 19900924