EP 2104079 A1 20090923 - Method and warning device, in particular smoke alarm
Title (en)
Method and warning device, in particular smoke alarm
Title (de)
Verfahren und Warnmelder, insbesondere Rauchmelder
Title (fr)
Procédé et alarme sonore, notamment détecteur de fumées
Publication
Application
Priority
DE 102008014991 A 20080319
Abstract (en)
The method involves producing acoustic signals in a measurement chamber (54) for a short-time, by a piezoceramic disk (68). Change in resonance characteristics of the measurement chamber is measured for delivery of error signals, when the resonance characteristics are measurably changed. A number of oscillations of the acoustic signals are measured after completion of the production of the acoustic signals. The number of oscillations is compared with a preset value. Decaying oscillations of the piezoceramic disk are counted. An independent claim is also included for an alarm device comprising a measurement chamber with an opening.
Abstract (de)
Verfahren zur Prüfung des freien Eintritts von Gas über mindestens eine Öffnung in eine Messkammer eines Warnmelders, bei dem in der Messkammer ein akustisches Signal erzeugt und die Änderung des Resonanzverhaltens der Messkammer gemessen wird, zwecks Abgabe eines Fehlersignals, wenn das Resonanzverhalten sich messbar geändert hat, wobei die Anzahl der Schwingungen des akustischen Signals nach Beendigung des akustischen Signals gemessen und mit einem vorgegebenen Wert verglichen wird.
IPC 8 full level
G08B 29/14 (2006.01)
CPC (source: EP US)
G08B 29/145 (2013.01 - EP US); G08B 17/113 (2013.01 - EP US)
Citation (applicant)
- JP H02128298 A 19900516 - NITTAN CO LTD
- EP 1870866 A1 20071226 - BRUNATA WAERMEMESSER HAGEN GMB [DE]
- EP 1857989 A1 20071121 - TECHEM ENERGY SERVICES GMBH [DE]
- DE 20108451 U1 20021002 - JOB LIZENZ GMBH & CO KG [DE]
- DE 8210633 U1 19820902
Citation (search report)
- [DA] JP H02128298 A 19900516 - NITTAN CO LTD
- [A] WO 0167072 A1 20010913 - MINE SAFETY APPLIANCES CO [US]
- [A] DE 4409900 C1 19950413 - PREUSSAG AG MINIMAX [DE]
- [A] JP H09196843 A 19970731 - FENWALL CONTROLS JAPAN LTD
Designated contracting state (EPC)
AT DE FR GB
Designated extension state (EPC)
AL BA RS
DOCDB simple family (publication)
US 2009267755 A1 20091029; AT E528737 T1 20111015; DE 102008014991 B3 20090312; EP 2104079 A1 20090923; EP 2104079 B1 20111012
DOCDB simple family (application)
US 40625709 A 20090318; AT 09002913 T 20090228; DE 102008014991 A 20080319; EP 09002913 A 20090228