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. 24, 1982
Filed:
May. 27, 1980
Henri H Hoge, Baltimore, MD (US);
Enertron, Inc., Baltimore, MD (US);
Abstract
A lighting feedback control system for applying AC power to at least one lamp, which includes a conduction angle controlled phase switching circuit connected in series with the lamp and an AC power source for switching power across the lamp, and a line switching circuit for enabling the application of AC power to the lamp through the phase switching circuit. A light sensor is provided for generating a light control signal indicative of the amount of ambient light present in the predetermined location. Coupled to the light sensing circuit is a phase angle conduction control circuit which generates and applies to a control terminal of the phase switching circuit a phase control signal to control the phase angle conduction time of the phase switching circuit based on the amount of ambient light measured by the light sensing circuit to maintain a constant level of lighting. Integrated within the phase angle conduction control circuit is an RC filter circuit which gradually increases the phase angle conduction time switching circuit from zero, or a predetermined minimum value, to a steady state phase angle conduction time based on the ambient light conditions sensed by the light sensing circuit, after power enabling by the line switching circuit.