JPS52119283A - False alarm checking smoke detector using one beam - Google Patents

False alarm checking smoke detector using one beam

Info

Publication number
JPS52119283A
JPS52119283A JP3453576A JP3453576A JPS52119283A JP S52119283 A JPS52119283 A JP S52119283A JP 3453576 A JP3453576 A JP 3453576A JP 3453576 A JP3453576 A JP 3453576A JP S52119283 A JPS52119283 A JP S52119283A
Authority
JP
Japan
Prior art keywords
smoke detector
false alarm
alarm checking
checking smoke
detecting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP3453576A
Other languages
Japanese (ja)
Inventor
Yuji Yamamoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP3453576A priority Critical patent/JPS52119283A/en
Publication of JPS52119283A publication Critical patent/JPS52119283A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/47—Scattering, i.e. diffuse reflection
    • G01N21/49—Scattering, i.e. diffuse reflection within a body or fluid
    • G01N21/53—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke
    • G01N21/534—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke by measuring transmission alone, i.e. determining opacity

Abstract

PURPOSE:Detecting accuracy of the smoke detector is improved by transmitting a light beam having convergency such as a laser beam within a fire-alert zone and detecting the quantity at which the intensity of the beam attenuates by passing through the medium in air, by means of a photo detector.
JP3453576A 1976-03-31 1976-03-31 False alarm checking smoke detector using one beam Pending JPS52119283A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3453576A JPS52119283A (en) 1976-03-31 1976-03-31 False alarm checking smoke detector using one beam

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3453576A JPS52119283A (en) 1976-03-31 1976-03-31 False alarm checking smoke detector using one beam

Publications (1)

Publication Number Publication Date
JPS52119283A true JPS52119283A (en) 1977-10-06

Family

ID=12416963

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3453576A Pending JPS52119283A (en) 1976-03-31 1976-03-31 False alarm checking smoke detector using one beam

Country Status (1)

Country Link
JP (1) JPS52119283A (en)

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