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:
Jun. 23, 1987
Filed:
Dec. 12, 1985
Hiromitsu Ishii, Chiba, JP;
Hochiki Kabushiki Kaisha, Tokyo, JP;
Abstract
A light-attenuation type fire detector assembly of the present invention comprises a light emission drive section including a light emitter for radiating light having an intensity corresponding to an input signal level; a smoke detecting section including a light receiver which directly receives the light radiated from the light emission drive section and is adapted to output a detection signal corresponding to the received light amount of the light receiver; a smoke amount computing section for computing the amount of smoke based on the detection signal from the smoke detecting section; a delay circuit for retarding input of the detection signal from the smoke detecting section to the light emission drive section for a predetermined time; and a control section for repeating the operations of the light emission drive section, the smoke detecting section and the delay circuit and generating a control signal after a predetermined period of time has been passed or a predetermined times of operation has been done to drive the smoke amount computing section, and wherein the amount of smoke is computed during a time when said smoke amount computing section is driven based on the smoke detection signal input to said smoke amount computing section to detect if there is attenuation in the radiated light due to smoke between the light emitter and the light receiver.