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Hitachi Ltd
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Hitachi Ltd
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Application filed by Hitachi LtdfiledCriticalHitachi Ltd
Priority to JP4244876ApriorityCriticalpatent/JPS52126197A/en
Publication of JPS52126197ApublicationCriticalpatent/JPS52126197A/en
PURPOSE: A high sensitive automatic fire sensor is installed at fire detecting position and an alarm is generated without direct transmission of a detecting signal by informing the fire to a person in the position where the sensor is installed, so that fire at the extremely early stage is detected and a fire alarm which has few error is generated.