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Publication of FR935179ApublicationCriticalpatent/FR935179A/fr
G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
G08B19/00—Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow
G08B19/005—Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow combined burglary and fire alarm systems
G—PHYSICS
G08—SIGNALLING
G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
G08B13/00—Burglar, theft or intruder alarms
G08B13/16—Actuation by interference with mechanical vibrations in air or other fluid
G08B13/1609—Actuation by interference with mechanical vibrations in air or other fluid using active vibration detection systems
G08B13/1618—Actuation by interference with mechanical vibrations in air or other fluid using active vibration detection systems using ultrasonic detection means
G08B13/1627—Actuation by interference with mechanical vibrations in air or other fluid using active vibration detection systems using ultrasonic detection means using Doppler shift detection circuits
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FR935179D1946-10-011946-10-01Procédé et dispositif pour la détection des mouvements au moyen d'un système d'ondes stationnaires acoustiques
ExpiredFR935179A
(fr)