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:
Nov. 07, 1978
Filed:
Mar. 14, 1977
Applicant:
Inventor:
Donald F Steele, Cohasset, MA (US);
Assignee:
Electro Signal Lab, Inc., Rockland, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N / ; G01B / ; G01N / ;
U.S. Cl.
CPC ...
356338 ; 250574 ; 340630 ; 356439 ;
Abstract
An optical smoke detector has a housing which forms a dark chamber into which light is directed on a path viewed by a photocell. Light scattered from the path by smoke causes the cell to trigger an alarm. The housing includes an interior wall around the dark chamber and an exterior wall exposed to ambient light. A wire mesh extending between offset ports in the exterior and interior walls screens insects from the chamber and obstructs light from passing directly to the interior part.