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:
Oct. 11, 1977
Filed:
Jan. 07, 1976
Sung Chuel Lee, Bridgeport, CT (US);
Vaclav Oldrich Podany, Norwalk, CT (US);
Hilario Simoes Costa, New Rochelle, NY (US);
General Signal Corporation, Rochester, NY (US);
Abstract
Smoke detection apparatus including a pair of photoelectric cells which receive illumination in a predetermined ratio from a very low level light source. An improved simulating device is included for the purpose of testing the correct functioning of the alarm system connected to a sensing circuit formed by the photocells. The effects normally produced by smoke present in a chamber are simulated by selectively directing light from an auxiliary light source onto the sensing or 'reflected' cell in the sensing circuit. In addition, a specially designed and constructed sensor head is provided for avoiding discrepancies in the placement of the critical elements; moreover, improved flow of any smoke present is promoted by the specific geometry of the sensor head. Also, discrepancies between the desired and actual ratio of illumination received by the respective photocells can be readily adjusted for electrically, and the light ratio between photocells can be changed by suitably adjusting the degree of illumination received by the direct cell.