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:
Apr. 01, 1997
Filed:
May. 03, 1995
Applicant:
Inventors:
James F Wiemeyer, Homer Township, IL (US);
Mark Bohanon, Lisle, IL (US);
Assignee:
Pittway Corporation, Chicago, IL (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
340628 ; 340630 ; 250573 ; 250574 ;
Abstract
A self-testable photoelectric smoke detector incorporates a housing which defines an internal smoke chamber. The housing carries a laser diode and a radiation sensor along with a supplemental source of test radiant energy. When a test is initiated, the operational characteristics of the laser diode are monitored simultaneously with energizing the source of test radiant energy. Signals from a scattered radiant energy sensor are evaluated via control circuitry, along with signals indicative of performance of the laser diode to determine whether or not the laser diode as well as the radiation sensor are functioning properly.