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. 13, 2013
Filed:
Dec. 01, 2010
Takahiro Kawashima, Tokyo, JP;
Takahiro Kawashima, Tokyo, JP;
Nohmi Bosai Ltd., Tokyo, JP;
Abstract
Provided is a photoelectric smoke sensor capable of correcting a sensitivity according to a state of contamination. The photoelectric smoke sensor includes: a storage section () for storing a zero detection value VN and an initial zero detection value; a moving average value calculating section () for calculating a moving average value of detection AD values output from a detection portion (); a zero detection value updating section () for calculating a new zero detection value VN when a sensitivity of the detection portion is decreased as compared with that in an initial state, and in addition, when a rate of change in the moving average value with respect to the zero detection value VN exceeds a predetermined value; a detection AD value correcting section () for correcting the detection value; and a smoke-density computing section () for converting the corrected detection value into smoke-density data.