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. 11, 1995
Filed:
Oct. 26, 1993
Lawrence W Speaker, Hendersonville, NC (US);
General Electric Company, Schenectady, NY (US);
Abstract
A lead ballast circuit with power regulation for a gas discharge lamp includes an input pair of conductors for receiving an a.c. supply voltage, the magnitude of which voltage fluctuates within a known range. Further included is an output pair of conductors for supplying a driving voltage to the lamp. A lead inductor having a magnetic core and a lead capacitance serially connected to the lead inductor between an input, and an output, conductor are included. The inductive impedance of the lead inductor is less than the capacitive impedance of the lead capacitance whereby the aggregate impedance of the serially connected inductor and capacitance is capacitive rather than inductive. The lead ballast circuit also includes a power factor-correcting inductor connected across the input conductor pair, and having a magnetic core that shares a leg in common with the magnetic core of the lead inductor. The magnetic cores of the lead and power factor-correcting inductors are constructed so that magnetic flux in the common leg increases in saturation as the a.c. supply voltage increases within the mentioned fluctuation range, hence reducing the inductive impedance of the lead inductor and consequently increasing the mentioned aggregate impedance, whereby, as the a.c. supply voltage increases in the fluctuation range, an increasing amount of such voltage appears across the increasing aggregate impedance so as to maintain the voltage and hence power of the lamp within a regulated range.