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:
Feb. 17, 1998
Filed:
Apr. 05, 1996
William J Rattman, Orlando, FL (US);
Zhexin Mi, Toronto, CA;
Digital Security Controls Ltd., Downsview, CA;
Abstract
The present invention provides for a smoke detection chamber and a photoelectric smoke detector containing the smoke detection chamber. The smoke detection chamber has side walls with openings provided therein for ingress and egress of smoke particles, a top and a bottom. A photoemitting diode is mounted in a mounting arrangement in the side wall of the smoke detection chamber to transmit a light beam across the smoke detection chamber without directly impinging upon either the top or the bottom surfaces. The bottom of the smoke detection chamber has an opening with a shielding arrangement thereabout open to the chamber located between the centerline of the smoke detection chamber and the mounting arrangement in the side wall of the chamber. A photodiode detector is positioned generally in the opening so that it views into the smoke detection chamber through the opening and shielding arrangement, the shielding arrangement shielding the photodiode detector from incident light which may be present in the smoke detector chamber while providing for a diverging field of view of the photodiode detector. The intersection of the field of view of the photodiode detector and the light beam of the photoemitting diode defines a detection volume contained within the smoke detection chamber located close to the photoemitting diode and the photodiode detector and spaced from the surfaces of the smoke detection chamber.