The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 21, 2018
Filed:
Jun. 23, 2016
Fenwal Controls of Japan, Ltd., Tokyo, JP;
Masao Iguchi, Tokyo, JP;
Tadayuki Shibuya, Tokyo, JP;
Kanji Numao, Tokyo, JP;
Shintaro Masumoto, Tokyo, JP;
Fenwal Controls of Japan, Ltd., Tokyo, JP;
Abstract
Provided is an explosion-proofed photoelectric smoke detector capable of preventing the surrounding gas from taking fire generated by an explosion inside it and of eliminating filling spaces around a light-emitting device and a light-receiving device with resin, thereby checking explosions due to deterioration of the resin, which enables the detector to be used, with the devices exposed to gases in explosion-proof zones. The light emitting/receiving devices are arranged outside of an explosion-proof enclosure having a circuit compartment. They respectively have hollow cylinders A and B, light emitting/receiving elements, and light-guiding members A and B for transmitting emitted light and guiding received light, wherein a gap between the tube wall of each hollow cylinder and each light-guiding member and a length of each member between an opening formed in each cylinder and a light exiting/entering end thereof enable the devices to prevent fire generated inside the detector from leaking out thereof.