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Patent Searching and Data


Title:
ALARM DEVICE
Document Type and Number:
WIPO Patent Application WO/2018/139499
Kind Code:
A1
Abstract:
The objective of the present invention is to provide an alarm device that is able to maintain the precision with which a substance to be detected is detected. This alarm device is equipped with: a detection means for detecting smoke by radiating a detection light toward a detection space 34 for detecting smoke contained in a gas; and an inside labyrinth 36 for preventing disturbance light from entering the detection space 34, said inside labyrinth being provided so as to cover the outer edge of the detection space 34. The detection means is equipped with a light-emitting unit that radiates detection light, and a light-receiving unit that receives the detection light radiated by the light-emitting unit. At least a portion of the side surfaces of the inside labyrinth 36 on the detection space 34 side is formed in a flat shape capable of preventing the detection light reflected by the inside labyrinth 36 from entering into a field-of-view portion RV of the light-receiving unit in the detection space 34.

Inventors:
SHIMADZU TOMOHIKO (JP)
Application Number:
PCT/JP2018/002167
Publication Date:
August 02, 2018
Filing Date:
January 24, 2018
Export Citation:
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Assignee:
HOCHIKI CO (JP)
International Classes:
G08B17/107; G08B17/10
Foreign References:
JPH04160697A1992-06-03
JP2010039936A2010-02-18
Other References:
See also references of EP 3576062A4
Attorney, Agent or Firm:
SAITO Tatsuya (JP)
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