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:
May. 05, 1998
Filed:
Dec. 07, 1995
Peter W Shackle, Arlington Heights, IL (US);
Randy G Russell, Glen Ellyn, IL (US);
Kent E Crouse, Haltom City, TX (US);
Ronald J Bezdon, Schaumburg, IL (US);
Energy Savings, Inc., Schaumburg, IL (US);
Abstract
An electronic ballast includes an inverter producing pulses having a DC component, an output circuit connecting the filaments of one or more lamps in series, and a control circuit for detecting direct current through the filaments. The control circuit includes a capacitor charged by the DC component. When the voltage on the capacitor reaches a predetermined value, the ballast applies a high voltage to the lamps. The predetermined value is not reached unless a direct current passes from the output of the inverter through all lamp filaments to the capacitor. If a lamp filament is not intact, the inverter will not apply high voltage to the lamp.